So far,a clear understanding about the relationship of variable energy band structure with the corresponding charge-discharge process of energy storage materials is still lacking.Here,using optical spectroscopy(red-gr...So far,a clear understanding about the relationship of variable energy band structure with the corresponding charge-discharge process of energy storage materials is still lacking.Here,using optical spectroscopy(red-green-blue(RGB)value,reflectivity,transmittance,UV-vis,XPS,UPS)to studyα-Co(OH)_(2) electrode working in KOH electrolyte as the research object,we provide direct experimental evidence that:(1)The intercalation of OH-ions will reduce the valence/conduction band(VB and CB)and band gap energy(Eg)values;(2)The deintercalation of OH-ions corresponds with the reversion of VB,CB and E_(g) to the initial values;(3)The color of Co(OH)_(2) electrode also exhibit regular variations in RGB value during the charge-discharge process.展开更多
Supercapacitors are favorable energy storage devices in the field of emerging energy technologies with high power density,excellent cycle stability and environmental benignity.The performance of supercapacitors is def...Supercapacitors are favorable energy storage devices in the field of emerging energy technologies with high power density,excellent cycle stability and environmental benignity.The performance of supercapacitors is definitively influenced by the electrode materials.Nickel sulfides have attracted extensive interest in recent years due to their specific merits for supercapacitor application.However,the distribution of electrochemically active sites critically limits their electrochemical performance.Notable improvements have been achieved through various strategies such as building synergetic structures with conductive substrates,enhancing the active sites by nanocrystallization and constructing nanohybrid architecture with other electrode materials.This article overviews the progress in the reasonable design and preparation of nickel sulfides and their composite electrodes combined with various bifunctional electric double-layer capacitor(EDLC)-based substances(e.g.,graphene,hollow carbon)and pseudocapacitive materials(e.g.,transition-metal oxides,sulfides,nitrides).Moreover,the corresponding electrochemical performances,reaction mechanisms,emerging challenges and future perspectives are briefly discussed and summarized.展开更多
The thermal energy storage phase change material used for building has been prepared with a few of fatty acids based on the principle of binary low eutectic point. The thermal behaviors such as phase transition temper...The thermal energy storage phase change material used for building has been prepared with a few of fatty acids based on the principle of binary low eutectic point. The thermal behaviors such as phase transition temperature and enthalpy of compound energy storage material are researched through differential scanning calorimeter(DSC) and scanning electron microscope(SEM) . The results show that the thermal energy storage phase change composite material can be used in the wall panels well as its higher latent heat.展开更多
Rechargeable batteries and supercapacitors are widely investigated as the most important electrochemical energy storage devices nowadays due to the booming energy demand for electric vehicles and hand-held electronics...Rechargeable batteries and supercapacitors are widely investigated as the most important electrochemical energy storage devices nowadays due to the booming energy demand for electric vehicles and hand-held electronics. The large surface-area-to-volume ratio and internal surface areas endow two-dimensional(2D) materials with high mobility and high energy density; therefore, 2D materials are very promising candidates for Li ion batteries and supercapacitors with comprehensive investigations. In 2011, a new kind of 2D transition metal carbides, nitrides and carbonitrides, MXene, were successfully obtained from MAX phases. Since then about 20 different kinds of MXene have been prepared. Other precursors besides MAX phases and even other methods such as chemical vapor deposition(CVD) were also applied to prepare MXene, opening new doors for the preparation of new MXene. Their 2D nature and good electronic properties ensure the inherent advantages as electrode materials for electrochemical energy storage. In this review, we summarize the recent progress in the development of MXene with emphasis on the applications to electrochemical energy storage. Also, future perspective and challenges of MXene-based materials are briefly discussed regrading electrochemical energy storage.展开更多
Graphene, a single layer of graphite, has been one of the first real two dimensional (2D) materials isolated in 2004. Thus, graphene is becoming a cutting edge material that opens up new horizons to a whole family o...Graphene, a single layer of graphite, has been one of the first real two dimensional (2D) materials isolated in 2004. Thus, graphene is becoming a cutting edge material that opens up new horizons to a whole family of 2D materials beyond the limited current applicability of graphene. The unique advantages of graphene and analogue 2D materials, such as atomic-scale thickness, high specific surface area, mechanically flexible robustness, superior storage capacity, endow them as high-performance electrodes lbr electrochemical energy storage devices. Although it is hard to say whether or not graphene and 2D materials will be implemented in future energy technologies, the recent achievements in this field demonstrate that their roles will be noticeable in the near future.展开更多
Electrochemical energy storage systems with high specific energy and power as well as long cyclic stability attract increasing attention in new energy technologies. The principles for rational design of electrodes are...Electrochemical energy storage systems with high specific energy and power as well as long cyclic stability attract increasing attention in new energy technologies. The principles for rational design of electrodes are discussed to reduce the activation, concentration, and resistance overpotentials and improve the active ma- terial efficiency in order to simultaneously achieve high specific energy and power. Three dimensional (3D) nanocomposites are currently considered as promising electrode materials due to their large surface area, reduced electronic and ionic diffusion distances, and synergistic effects. This paper reviews the most recent progress on the synthesis and application of 3D thin film nanoelectrode arrays based on aligned carbon nan- otubes (ACNTs) directly grown on metal foils for energy storages and special attentions are paid on our own representative works. These novel 3D nanoelectrode arrays on metal foil exhibit improved electrochemical performances in terms of specific energy, specific power and cyclic stability due to their unique structures. In this active materials coated ACNTs over conductive substrate structures, each component is tailored to address a different demand. The electrochemical active material is used to store energy, while the ACNTs are employed to provide a large surface area to support the active material and nanocable arrays to facilitate the electron transport. The thin film of active materials can not only reduce ion transport resistance by shorten- ing the diffusion length but also make the film elastic enough to tolerate significant volume changes during charge and discharge cycles. The conductive substrate is used as the current collector and the direct contact of the ACNT arrays with the substrate reduces significantly the contact resistance. The principles obtained from ACNT based electrodes are extended to aligned graphene based electrodes. Similar improvements have been achieved which confirms the reliability of the principles obtained. In addition, we also discuss and view the ongoing trends in development of aligned carbon nanostructures based electrodes for energy storage.展开更多
In this paper, the mechanical and thermal properties of a sand-clay ceramic with additives coal bottom ash (CBA) waste from incinerator coal power plant are investigated to develop an alternative material for thermal ...In this paper, the mechanical and thermal properties of a sand-clay ceramic with additives coal bottom ash (CBA) waste from incinerator coal power plant are investigated to develop an alternative material for thermal energy storage (TES). Ceramic balls are developed at 1000°C and 1060°C using sintering or firing method. The obtained ceramics were compressed with a compression machine and thermally analyse using Decagon devise KD2 Pro thermal analyser. A muffle furnace was also used for thermal cycling at 610°C. It was found that the CBA increased the porosity, which resulted in the increase of the axial tensile strength reaching 3.5 MPa for sand-clay and ash ceramic. The ceramic balls with the required tensile strength for TES were selected. Their volumetric heat capacity, and thermal conductivity range respectively from 2.4075 MJ·m-3·°C-1 to 3.426 MJ·m-3·°C-1 and their thermal conductivity from 0.331 Wm-1·K-1, to 1.014 Wm-1·K-1 depending on sand origin, size and firing temperature. The selected formulas have good thermal stability because the most fragile specimens after 60 thermal cycles did not present any cracks. These properties allow envisioning the use of the ceramic balls developed as filler material for thermocline thermal energy storage (structured beds) in Concentrating Solar Power plants. And for other applications like solar cooker and solar dryer.展开更多
More than 4600 papers in the field of Mg and Mg alloys were published and indexed in the Web of Science(WoS)Core Collection database in 2022.The bibliometric analyses indicate that the microstructure,mechanical proper...More than 4600 papers in the field of Mg and Mg alloys were published and indexed in the Web of Science(WoS)Core Collection database in 2022.The bibliometric analyses indicate that the microstructure,mechanical properties,and corrosion of Mg alloys are still the main research focus.Bio-Mg materials,Mg ion batteries and hydrogen storage Mg materials have attracted much attention.Notable contributions to the research and development of magnesium alloys were made by Chongqing University(>200 papers),Chinese Academy of Sciences,Shanghai Jiao Tong University,and Northeastern University(>100 papers)in China,Helmholtz Zentrum Hereon in Germany,Ohio State University in the USA,the University of Queensland in Australia,Kumanto University in Japan,and Seoul National University in Korea,University of Tehran in Iran,and National University of Singapore in Singapore,etc.This review is aimed to summarize the progress in the development of structural and functional Mg and Mg alloys in 2022.Based on the issues and challenges identified here,some future research directions are suggested.展开更多
Supercapacitors are appealing energy storage devices for their promising features like high power density,outstanding cycling stability,and a quick charge–discharge cycle.The exceptional life cycle and ultimate power...Supercapacitors are appealing energy storage devices for their promising features like high power density,outstanding cycling stability,and a quick charge–discharge cycle.The exceptional life cycle and ultimate power capability of supercapacitors are needed in the transportation and renewable energy generation sectors.Hence,predicting the capacitance and lifecycle of supercapacitors is significant for selecting the suitable material and planning replacement intervals for supercapacitors.In addition,system failures can be better addressed by accurately forecasting the lifecycle of SCs.Recently,the use of machine learning for performance prediction of energy storage materials has drawn increasing attention from researchers globally because of its superiority in prediction accuracy,time efficiency,and costeffectiveness.This article presents a detailed review of the progress and advancement of ML techniques for the prediction of capacitance and remaining useful life(RUL)of supercapacitors.The review starts with an introduction to supercapacitor materials and ML applications in energy storage devices,followed by workflow for ML model building for supercapacitor materials.Then,the summary of machine learning applications for the prediction of capacitance and RUL of different supercapacitor materials including EDLCs(carbon based materials),pesudocapacitive(oxides and composites)and hybrid materials is presented.Finally,the general perspective for future directions is also presented.展开更多
This paper discusses composite materials based on inorganic salts for medium- and high-temperature thermal energy storage application. The composites consist of a phase change material (PCM), a ceramic material, and...This paper discusses composite materials based on inorganic salts for medium- and high-temperature thermal energy storage application. The composites consist of a phase change material (PCM), a ceramic material, and a high thermal conductivity material. The ceramic material forms a microstructural skeleton for encapsulation of the PCM and structural stability of the composites; the high thermal conductivity material enhances the overall thermal conductivity of the composites. Using a eutectic salt of lithium and sodium carbonates as the PCM, magnesium oxide as the ceramic skeleton, and either graphite flakes or carbon nanotubes as the thermal conductivity enhancer, we produced composites with good physical and chemical stability and high thermal conductivity. We found that the wettability of the molten salt on the ceramic and carbon materials significantly affects the microstructure of the composites.展开更多
More than 4000 papers in the field of Mg and Mg alloys were published and indexed in Web of Science(WoS)Core Collection database in 2021.The bibliometric analyses indicate that the microstructure,mechanical properties...More than 4000 papers in the field of Mg and Mg alloys were published and indexed in Web of Science(WoS)Core Collection database in 2021.The bibliometric analyses indicate that the microstructure,mechanical properties,and corrosion of Mg alloys still are the main research focus.Mg ion batteries and hydrogen storage Mg materials have attracted much attention.Significant contributions to the research and development of magnesium alloys were made by Chongqing University,Shanghai Jiaotong University,and Chinese Academy of Sciences in China,Helmholtz Zentrum Hereon in Germany,Ohio State University in the United States,the University of Queensland in Australia,Kumanto University in Japan,and Seoul National University in Korea,University of Tehran in Iran,etc..This review is aimed to summarize the progress in the development of structural and functional Mg and Mg alloys in 2021.Based on the issues and challenges identified here,some future research directions are suggested.展开更多
Modern wearable electronics are thirsty for flexible, lightweight energy storage and supply devices. Flexible fiber-shaped supercapacitors, possess good flexibility, high power density, fast charging capability and lo...Modern wearable electronics are thirsty for flexible, lightweight energy storage and supply devices. Flexible fiber-shaped supercapacitors, possess good flexibility, high power density, fast charging capability and long cycle life, becoming a promising option for wearable devices. The past decade has witnessed the emergence of graphene fiber based supercapacitors(GFSCs) as one of the most active vicinity in fiber-supercapactiors, for their excellent properties including high surface area, chemical stability, excellent electrical conductivity, lightweight and mechanical properties. In this perspective, we introduced the basic energy storage mechanisms of GFSCs, followed by the analysis in improving their overall performances, recent advances, and a conclusive discussion on the challenges and opportunities.展开更多
The energy materials performance is intrinsically determined by structures from the average lattice structure to the atom arrangement, valence, and distribution of the containing transition metal(TM) elements. Underst...The energy materials performance is intrinsically determined by structures from the average lattice structure to the atom arrangement, valence, and distribution of the containing transition metal(TM) elements. Understanding the mechanism of the structure transition and atom rearrangement via synthesis or processing is key to expediting the exploration of excellent energy materials. In this work, in situ neutron scattering is employed to reveal the real-time structure evolution, including the TM-O bonds, lattice,TM valence and the migration of the high-voltage spinel cathode LiNi_(0.5)Mn_(1.5)O_(4). The transition-metalmediated spinel destabilization under the annealing at the oxygen-deficient atmosphere is pinpointed.The formation of Mn^(3+) is correlated to the TM migration activation, TM disordered rearrangement in the spinel, and the transition to a layered-rocksalt phase. The further TM interdiffusion and Mn^(3+) reduction are also revealed with multi-stage thermodynamics and kinetics. The mechanisms of phase transition and atom migrations as functions of temperature, time and atmosphere present important guidance on the synthesis in various-valence element containing oxides.展开更多
Controlling the concentration of defects in reduced graphene oxide (rGO) to tailor its electrical and physicochemical properties has remained a significant challenge. We report that extent of microwave (MW)-driven...Controlling the concentration of defects in reduced graphene oxide (rGO) to tailor its electrical and physicochemical properties has remained a significant challenge. We report that extent of microwave (MW)-driven annealing of rGO is influenced significantly by its bulk density, which allows us to vary its defect density and crystallite size over wide ranges by controlling this parameter. Extent of anneal- ing was investigated by multiple techniques including Raman and X-ray photoelectron spectroscopies, and electrical conductivity measurements. Improved corrosion resistance of rGOs upon annealing was ex- amined by cyclic voltammetry in H_2SO_4 electrolyte and temperature-programmed oxidation of rGO. Our results indicate that a low bulk density of rGO facilitates defect annealing, yielding high-quality carbon with 99.3 wt% purity, oxidative resistance as high as graphite powder, and an electrical conductivity of 36,000 S m-1 in the compressed powder form. These results demonstrate a prospective synthesis route for tailor-made nanocarbons from rGO through MW-driven annealing.展开更多
Traditional dual-ion lithium salts have been widely used in solid polymer lithium-metal batteries(LMBs).Nevertheless, concentration polarization caused by uncontrolled migration of free anions has severely caused the ...Traditional dual-ion lithium salts have been widely used in solid polymer lithium-metal batteries(LMBs).Nevertheless, concentration polarization caused by uncontrolled migration of free anions has severely caused the growth of lithium dendrites. Although single-ion conductor polymers(SICP) have been developed to reduce concentration polarization, the poor ionic conductivity caused by low carrier concentration limits their application. Herein, a dual-salt quasi-solid polymer electrolyte(QSPE), containing the SICP network as a salt and traditional dual-ion lithium salt, is designed for retarding the movement of free anions and simultaneously providing sufficient effective carriers to alleviate concentration polarization. The dual salt network of this designed QSPE is prepared through in-situ crosslinking copolymerization of SICP monomer, regular ionic conductor, crosslinker with the presence of the dual-ion lithium salt,delivering a high lithium-ion transference number(0.75) and satisfactory ionic conductivity(1.16 × 10^(-3) S cm^(-1) at 30 ℃). Comprehensive characterizations combined with theoretical calculation demonstrate that polyanions from SICP exerts a potential repulsive effect on the transport of free anions to reduce concentration polarization inhibiting lithium dendrites. As a consequence, the Li||LiFePO_4 cell achieves a long-cycle stability for 2000 cycles and a 90% capacity retention at 30 ℃. This work provides a new perspective for reducing concentration polarization and simultaneously enabling enough lithiumions migration for high-performance polymer LMBs.展开更多
This article reports that extremely thin nanobelts(thickness~10 nm)exhibit pseudocapacitive(PC)charge storage in the asymmetric supercapacitor(ASC)configuration,while show battery-type charge storage in their single e...This article reports that extremely thin nanobelts(thickness~10 nm)exhibit pseudocapacitive(PC)charge storage in the asymmetric supercapacitor(ASC)configuration,while show battery-type charge storage in their single electrodes.Two types of nanobelts,viz.NiO-Co_(3)O_(4) hybrid and spinal-type NiCo_(2)O_(4),developed by electrospinning technique are used in this work.The charge storage behaviour of the nanobelts is benchmarked against their binary metal oxide nanowires,i.e.,NiO and Co_(3)O_(4),as well as a hybrid of similar chemistry,CuO-Co_(3)O_(4).The nanobelts have thickness of~10 nm and width~200 nm,whereas the nanowires have diameter of~100 nm.Clear differences in charge storage behaviours are observed in NiO-Co_(3)O_(4) hybrid nanobelts based ASCs compared to those fabricated using the other materials-the former showed capacitive behav-iour whereas the others revealed battery-type discharge behaviour.Origin of pseudocapacitance in nanobelts based ASCs is shown to arise from their nanobelts morphology with thickness less than typical electron diffusion lengths(~20 nm).Among all the five type of devices fabricated,the NiO-Co_(3)O_(4) hybrid ASCs exhibited the highest specific energy,specific power and cycling stability.展开更多
Electrode material has been cited as one of the most important determining factors in classifying an energy storage system’s charge storage mechanism,i.e.,as battery-type or supercapacitive-type.In this paper,we show...Electrode material has been cited as one of the most important determining factors in classifying an energy storage system’s charge storage mechanism,i.e.,as battery-type or supercapacitive-type.In this paper,we show that along with the electrode material,the electrolyte also plays a role in determining the charge storage behaviour of the system.For the purpose of our research,we chose multi-elemental spinal type CuMn_(2)O_(4) metal oxide nanofibers to prove the hypothesis.The material is synthesized as nanofibers of diameter~120 to 150 nm in large scales by a pilot scale electrospinning set up.It was then tested in three different electrolytes(1 M KOH,1 M Na_(2)SO_(4) and 1 M Li_(2)SO_(4)),two of which are neutral and the third is alkaline(KOH).The cyclic voltammograms and the galvanostatic charge-discharge of the electrode material in a three-electrode sys-tem measurement showed that it exhibit different charge storage mechanism in different electrolyte solutions.For the neutral electrolytes,a capacitive behaviour was observed whereas a battery-type behaviour was seen for the alkaline electrolyte.This leads us to conclude that the charge storage mechanism,along with the active material,also depends on the electrolyte used.展开更多
This short communication reports our recent work on the synthesis and characterisation ofmicrocapsules of phase change materials using silica as the shell material through a one-step method. The method uses no surfact...This short communication reports our recent work on the synthesis and characterisation ofmicrocapsules of phase change materials using silica as the shell material through a one-step method. The method uses no surfactants or dispersants for stabilising the capsules. The results show that the one-step method allows the tuning of the size and polydispersity of the capsules, and the use of different core materials. Analyses of the capsules show that they contain about 65% phase change materials. The results also suggest no need for a stabilising agent due to self-stabilisation by the amine groups. Further work is underway to investigate the mechanical and thermal properties of the microcapsules and the scale-up of the method.展开更多
Benefiting from the diversity and subjective design feasibility of molecular structure, flexibility,lightweight, molecular level controllability, resource renewability and relatively low cost, polymeric electrode mate...Benefiting from the diversity and subjective design feasibility of molecular structure, flexibility,lightweight, molecular level controllability, resource renewability and relatively low cost, polymeric electrode materials are promising candidates for the next generation of sustainable energy resources and have attracted extensive attention for the foreseeable large scale applications. The conductive polymers have been utilized as electrode materials in the pioneer reports, which, however, have the disadvantages of low stability, low reversibility and slope voltage due to the delocalization of charges in the whole conjugated systems. The discovery of carbonyl materials aroused the interest of organic and polymeric materials for batteries again. This review presents the recent progress in carbonyl polymeric electrode materials for lithium-ion batteries, sodium-ion batteries and magnesium-ion batteries. This comprehensive review is expected to be helpful forarousing more interest of organic materials for met展开更多
With the increasing popularity of electric/hybrid vehicles and the rapid development of 3C electronics,there is a growing interest in high-rate energy storage systems.The rapid development and widespread adoption of l...With the increasing popularity of electric/hybrid vehicles and the rapid development of 3C electronics,there is a growing interest in high-rate energy storage systems.The rapid development and widespread adoption of lithiumion batteries(LIBs)can be attributed to their numerous advantages,including high energy density,high operating voltage,environmental friendliness,and lack of memory effect.However,the progress of LIBs is currently hindered by the limitations of energy storage materials,which serve as vital components.Therefore,there is an urgent need to address the development of a new generation of high-rate energy storage materials in order to overcome these limitations and further advance LIB technology.Niobium-based oxides have emerged as promising candidates for the fabrication of fast-charging Li-ion batteries due to their excellent rate capability and long lifespan.This review paper provides a comprehensive analysis of the fundamentals,methodologies,and electrochemistries of niobium-based oxides,with a specific focus on the evolution and creation of crystal phases of Nb_(2)O_(5),fundamental electrochemical behavior,and modification methods including morphology modulation,composite technology,and carbon coating.Furthermore,the review explores Nb_(2)O_(5)-derived compounds and related advanced characterization techniques.Finally,the challenges and issues in the development of niobiumbased oxides for high-rate energy storage batteries are discussed,along with future research perspectives.展开更多
基金supported by the National Natural Science Foundation of China(Nos.51972146,52072150).
文摘So far,a clear understanding about the relationship of variable energy band structure with the corresponding charge-discharge process of energy storage materials is still lacking.Here,using optical spectroscopy(red-green-blue(RGB)value,reflectivity,transmittance,UV-vis,XPS,UPS)to studyα-Co(OH)_(2) electrode working in KOH electrolyte as the research object,we provide direct experimental evidence that:(1)The intercalation of OH-ions will reduce the valence/conduction band(VB and CB)and band gap energy(Eg)values;(2)The deintercalation of OH-ions corresponds with the reversion of VB,CB and E_(g) to the initial values;(3)The color of Co(OH)_(2) electrode also exhibit regular variations in RGB value during the charge-discharge process.
基金the National Natural Science Foundation of China(Nos.51302079,51702138 and 51403193)the Natural Science Foundation of Hunan Province(No.2017JJ1008)the Key Research and Development Program of Hunan Province of China(No.2018GK2031)。
文摘Supercapacitors are favorable energy storage devices in the field of emerging energy technologies with high power density,excellent cycle stability and environmental benignity.The performance of supercapacitors is definitively influenced by the electrode materials.Nickel sulfides have attracted extensive interest in recent years due to their specific merits for supercapacitor application.However,the distribution of electrochemically active sites critically limits their electrochemical performance.Notable improvements have been achieved through various strategies such as building synergetic structures with conductive substrates,enhancing the active sites by nanocrystallization and constructing nanohybrid architecture with other electrode materials.This article overviews the progress in the reasonable design and preparation of nickel sulfides and their composite electrodes combined with various bifunctional electric double-layer capacitor(EDLC)-based substances(e.g.,graphene,hollow carbon)and pseudocapacitive materials(e.g.,transition-metal oxides,sulfides,nitrides).Moreover,the corresponding electrochemical performances,reaction mechanisms,emerging challenges and future perspectives are briefly discussed and summarized.
基金the National Support Projects of the Eleventh Five-year Plan (No. 2006BAJ02B01)the Special Research Projects of Shaanxi Province Education Department (No. 08JK316)the Key Discipline Construction Projects of Shaanxi Province for Funding Support
文摘The thermal energy storage phase change material used for building has been prepared with a few of fatty acids based on the principle of binary low eutectic point. The thermal behaviors such as phase transition temperature and enthalpy of compound energy storage material are researched through differential scanning calorimeter(DSC) and scanning electron microscope(SEM) . The results show that the thermal energy storage phase change composite material can be used in the wall panels well as its higher latent heat.
基金supported by Tianjin Municipal Science and Technology Commission(16PTSYJC00010)in China
文摘Rechargeable batteries and supercapacitors are widely investigated as the most important electrochemical energy storage devices nowadays due to the booming energy demand for electric vehicles and hand-held electronics. The large surface-area-to-volume ratio and internal surface areas endow two-dimensional(2D) materials with high mobility and high energy density; therefore, 2D materials are very promising candidates for Li ion batteries and supercapacitors with comprehensive investigations. In 2011, a new kind of 2D transition metal carbides, nitrides and carbonitrides, MXene, were successfully obtained from MAX phases. Since then about 20 different kinds of MXene have been prepared. Other precursors besides MAX phases and even other methods such as chemical vapor deposition(CVD) were also applied to prepare MXene, opening new doors for the preparation of new MXene. Their 2D nature and good electronic properties ensure the inherent advantages as electrode materials for electrochemical energy storage. In this review, we summarize the recent progress in the development of MXene with emphasis on the applications to electrochemical energy storage. Also, future perspective and challenges of MXene-based materials are briefly discussed regrading electrochemical energy storage.
文摘Graphene, a single layer of graphite, has been one of the first real two dimensional (2D) materials isolated in 2004. Thus, graphene is becoming a cutting edge material that opens up new horizons to a whole family of 2D materials beyond the limited current applicability of graphene. The unique advantages of graphene and analogue 2D materials, such as atomic-scale thickness, high specific surface area, mechanically flexible robustness, superior storage capacity, endow them as high-performance electrodes lbr electrochemical energy storage devices. Although it is hard to say whether or not graphene and 2D materials will be implemented in future energy technologies, the recent achievements in this field demonstrate that their roles will be noticeable in the near future.
基金support from NTNU Nanolab and financial supports from VISTA, Zhengzhou Research Institute of Chalco and Norwegian research council
文摘Electrochemical energy storage systems with high specific energy and power as well as long cyclic stability attract increasing attention in new energy technologies. The principles for rational design of electrodes are discussed to reduce the activation, concentration, and resistance overpotentials and improve the active ma- terial efficiency in order to simultaneously achieve high specific energy and power. Three dimensional (3D) nanocomposites are currently considered as promising electrode materials due to their large surface area, reduced electronic and ionic diffusion distances, and synergistic effects. This paper reviews the most recent progress on the synthesis and application of 3D thin film nanoelectrode arrays based on aligned carbon nan- otubes (ACNTs) directly grown on metal foils for energy storages and special attentions are paid on our own representative works. These novel 3D nanoelectrode arrays on metal foil exhibit improved electrochemical performances in terms of specific energy, specific power and cyclic stability due to their unique structures. In this active materials coated ACNTs over conductive substrate structures, each component is tailored to address a different demand. The electrochemical active material is used to store energy, while the ACNTs are employed to provide a large surface area to support the active material and nanocable arrays to facilitate the electron transport. The thin film of active materials can not only reduce ion transport resistance by shorten- ing the diffusion length but also make the film elastic enough to tolerate significant volume changes during charge and discharge cycles. The conductive substrate is used as the current collector and the direct contact of the ACNT arrays with the substrate reduces significantly the contact resistance. The principles obtained from ACNT based electrodes are extended to aligned graphene based electrodes. Similar improvements have been achieved which confirms the reliability of the principles obtained. In addition, we also discuss and view the ongoing trends in development of aligned carbon nanostructures based electrodes for energy storage.
文摘In this paper, the mechanical and thermal properties of a sand-clay ceramic with additives coal bottom ash (CBA) waste from incinerator coal power plant are investigated to develop an alternative material for thermal energy storage (TES). Ceramic balls are developed at 1000°C and 1060°C using sintering or firing method. The obtained ceramics were compressed with a compression machine and thermally analyse using Decagon devise KD2 Pro thermal analyser. A muffle furnace was also used for thermal cycling at 610°C. It was found that the CBA increased the porosity, which resulted in the increase of the axial tensile strength reaching 3.5 MPa for sand-clay and ash ceramic. The ceramic balls with the required tensile strength for TES were selected. Their volumetric heat capacity, and thermal conductivity range respectively from 2.4075 MJ·m-3·°C-1 to 3.426 MJ·m-3·°C-1 and their thermal conductivity from 0.331 Wm-1·K-1, to 1.014 Wm-1·K-1 depending on sand origin, size and firing temperature. The selected formulas have good thermal stability because the most fragile specimens after 60 thermal cycles did not present any cracks. These properties allow envisioning the use of the ceramic balls developed as filler material for thermocline thermal energy storage (structured beds) in Concentrating Solar Power plants. And for other applications like solar cooker and solar dryer.
基金This work was financially supported by the National Key Research and Development Program of China(No.2021YFB3701100)the National Natural Science Foundation of China(Nos.52171104 and U20A20234)+1 种基金the Chongqing Research Program of Basic Research and Frontier Technology,China(Nos.cstc2021ycjh-bgzxm0086 and 2019jcyj-msxmX0306)the fundamental Research funds for Central Universities,China(Nos.SKLMT-ZZKT-2022R04,2021CDJJMRH-001,and SKLMT-ZZKT-2022M12).
文摘More than 4600 papers in the field of Mg and Mg alloys were published and indexed in the Web of Science(WoS)Core Collection database in 2022.The bibliometric analyses indicate that the microstructure,mechanical properties,and corrosion of Mg alloys are still the main research focus.Bio-Mg materials,Mg ion batteries and hydrogen storage Mg materials have attracted much attention.Notable contributions to the research and development of magnesium alloys were made by Chongqing University(>200 papers),Chinese Academy of Sciences,Shanghai Jiao Tong University,and Northeastern University(>100 papers)in China,Helmholtz Zentrum Hereon in Germany,Ohio State University in the USA,the University of Queensland in Australia,Kumanto University in Japan,and Seoul National University in Korea,University of Tehran in Iran,and National University of Singapore in Singapore,etc.This review is aimed to summarize the progress in the development of structural and functional Mg and Mg alloys in 2022.Based on the issues and challenges identified here,some future research directions are suggested.
基金Shivaji University,Kolhapur for financial assistance through Research Strengthening Scheme。
文摘Supercapacitors are appealing energy storage devices for their promising features like high power density,outstanding cycling stability,and a quick charge–discharge cycle.The exceptional life cycle and ultimate power capability of supercapacitors are needed in the transportation and renewable energy generation sectors.Hence,predicting the capacitance and lifecycle of supercapacitors is significant for selecting the suitable material and planning replacement intervals for supercapacitors.In addition,system failures can be better addressed by accurately forecasting the lifecycle of SCs.Recently,the use of machine learning for performance prediction of energy storage materials has drawn increasing attention from researchers globally because of its superiority in prediction accuracy,time efficiency,and costeffectiveness.This article presents a detailed review of the progress and advancement of ML techniques for the prediction of capacitance and remaining useful life(RUL)of supercapacitors.The review starts with an introduction to supercapacitor materials and ML applications in energy storage devices,followed by workflow for ML model building for supercapacitor materials.Then,the summary of machine learning applications for the prediction of capacitance and RUL of different supercapacitor materials including EDLCs(carbon based materials),pesudocapacitive(oxides and composites)and hybrid materials is presented.Finally,the general perspective for future directions is also presented.
基金supported by the Focused Deployment Project of the Chinese Academy of Sciences(KGZD-EW-302-1)Key Technologies R&D Program of China(No.2012BAA03B03)+1 种基金Natural Science Foundation of China(Grant No.21106151)the UK Engineering and Physical Sciences Research Council(EPSRC)under grant EP/K002252/1
文摘This paper discusses composite materials based on inorganic salts for medium- and high-temperature thermal energy storage application. The composites consist of a phase change material (PCM), a ceramic material, and a high thermal conductivity material. The ceramic material forms a microstructural skeleton for encapsulation of the PCM and structural stability of the composites; the high thermal conductivity material enhances the overall thermal conductivity of the composites. Using a eutectic salt of lithium and sodium carbonates as the PCM, magnesium oxide as the ceramic skeleton, and either graphite flakes or carbon nanotubes as the thermal conductivity enhancer, we produced composites with good physical and chemical stability and high thermal conductivity. We found that the wettability of the molten salt on the ceramic and carbon materials significantly affects the microstructure of the composites.
基金support from the Guangdong Major Project of Basic and Applied Basic Research(2020B0301030006)National Natural Science Foundation of China(NSFC)(No.52071036)+1 种基金Key Research and Development Program of Zhejiang Province(No.2021C01086)the Fundamental Research Funds for the Central Universities Project(Nos.2021CDJCGJ009,SKLMT-ZZKT-2021M11)is also gratefully acknowledged.
文摘More than 4000 papers in the field of Mg and Mg alloys were published and indexed in Web of Science(WoS)Core Collection database in 2021.The bibliometric analyses indicate that the microstructure,mechanical properties,and corrosion of Mg alloys still are the main research focus.Mg ion batteries and hydrogen storage Mg materials have attracted much attention.Significant contributions to the research and development of magnesium alloys were made by Chongqing University,Shanghai Jiaotong University,and Chinese Academy of Sciences in China,Helmholtz Zentrum Hereon in Germany,Ohio State University in the United States,the University of Queensland in Australia,Kumanto University in Japan,and Seoul National University in Korea,University of Tehran in Iran,etc..This review is aimed to summarize the progress in the development of structural and functional Mg and Mg alloys in 2021.Based on the issues and challenges identified here,some future research directions are suggested.
基金supported by the National Natural Science Foundation of China(Nos.21325417 and 51533008)National Key R&D Program of China(No.2016YFA0200200)+1 种基金Fundamental Research Funds for the Central Universities(No.2017XZZX008-06)the China Postdoctoral Science Foundation(No.2017M621927)
文摘Modern wearable electronics are thirsty for flexible, lightweight energy storage and supply devices. Flexible fiber-shaped supercapacitors, possess good flexibility, high power density, fast charging capability and long cycle life, becoming a promising option for wearable devices. The past decade has witnessed the emergence of graphene fiber based supercapacitors(GFSCs) as one of the most active vicinity in fiber-supercapactiors, for their excellent properties including high surface area, chemical stability, excellent electrical conductivity, lightweight and mechanical properties. In this perspective, we introduced the basic energy storage mechanisms of GFSCs, followed by the analysis in improving their overall performances, recent advances, and a conclusive discussion on the challenges and opportunities.
基金supported by the Division of Materials Science and Engineering, Office of Basic Energy Sciences, U.S. Department of Energy (DOE)。
文摘The energy materials performance is intrinsically determined by structures from the average lattice structure to the atom arrangement, valence, and distribution of the containing transition metal(TM) elements. Understanding the mechanism of the structure transition and atom rearrangement via synthesis or processing is key to expediting the exploration of excellent energy materials. In this work, in situ neutron scattering is employed to reveal the real-time structure evolution, including the TM-O bonds, lattice,TM valence and the migration of the high-voltage spinel cathode LiNi_(0.5)Mn_(1.5)O_(4). The transition-metalmediated spinel destabilization under the annealing at the oxygen-deficient atmosphere is pinpointed.The formation of Mn^(3+) is correlated to the TM migration activation, TM disordered rearrangement in the spinel, and the transition to a layered-rocksalt phase. The further TM interdiffusion and Mn^(3+) reduction are also revealed with multi-stage thermodynamics and kinetics. The mechanisms of phase transition and atom migrations as functions of temperature, time and atmosphere present important guidance on the synthesis in various-valence element containing oxides.
基金supported by "Nanotechnology Platform" Program of the Ministry of Education, Culture, Sports, Science and Technology (MEXT), Japansupported by JSPS KAKENHI grant numbers 19656200, 26420774 and 16H04558
文摘Controlling the concentration of defects in reduced graphene oxide (rGO) to tailor its electrical and physicochemical properties has remained a significant challenge. We report that extent of microwave (MW)-driven annealing of rGO is influenced significantly by its bulk density, which allows us to vary its defect density and crystallite size over wide ranges by controlling this parameter. Extent of anneal- ing was investigated by multiple techniques including Raman and X-ray photoelectron spectroscopies, and electrical conductivity measurements. Improved corrosion resistance of rGOs upon annealing was ex- amined by cyclic voltammetry in H_2SO_4 electrolyte and temperature-programmed oxidation of rGO. Our results indicate that a low bulk density of rGO facilitates defect annealing, yielding high-quality carbon with 99.3 wt% purity, oxidative resistance as high as graphite powder, and an electrical conductivity of 36,000 S m-1 in the compressed powder form. These results demonstrate a prospective synthesis route for tailor-made nanocarbons from rGO through MW-driven annealing.
基金supported by the National Natural Science Foundation of China (52273081 and 22278329)the Natural Science Basic Research Program of Shaanxi (2022TD-27 and 2020-JC-09)+2 种基金Qin Chuangyuan Talent Project of Shaanxi Province (OCYRCXM2022-308)the State Key Laboratory for Electrical Insulation and Power Equipment (EIPE23125)the “Young Talent Support Plan” of Xi’an Jiaotong University。
文摘Traditional dual-ion lithium salts have been widely used in solid polymer lithium-metal batteries(LMBs).Nevertheless, concentration polarization caused by uncontrolled migration of free anions has severely caused the growth of lithium dendrites. Although single-ion conductor polymers(SICP) have been developed to reduce concentration polarization, the poor ionic conductivity caused by low carrier concentration limits their application. Herein, a dual-salt quasi-solid polymer electrolyte(QSPE), containing the SICP network as a salt and traditional dual-ion lithium salt, is designed for retarding the movement of free anions and simultaneously providing sufficient effective carriers to alleviate concentration polarization. The dual salt network of this designed QSPE is prepared through in-situ crosslinking copolymerization of SICP monomer, regular ionic conductor, crosslinker with the presence of the dual-ion lithium salt,delivering a high lithium-ion transference number(0.75) and satisfactory ionic conductivity(1.16 × 10^(-3) S cm^(-1) at 30 ℃). Comprehensive characterizations combined with theoretical calculation demonstrate that polyanions from SICP exerts a potential repulsive effect on the transport of free anions to reduce concentration polarization inhibiting lithium dendrites. As a consequence, the Li||LiFePO_4 cell achieves a long-cycle stability for 2000 cycles and a 90% capacity retention at 30 ℃. This work provides a new perspective for reducing concentration polarization and simultaneously enabling enough lithiumions migration for high-performance polymer LMBs.
基金This work is supported by the Research and Inno-vation Department of University Malaysia Pahang(http://ump.edu.my)under the Flagship Leap 3 Program(RDU172201).
文摘This article reports that extremely thin nanobelts(thickness~10 nm)exhibit pseudocapacitive(PC)charge storage in the asymmetric supercapacitor(ASC)configuration,while show battery-type charge storage in their single electrodes.Two types of nanobelts,viz.NiO-Co_(3)O_(4) hybrid and spinal-type NiCo_(2)O_(4),developed by electrospinning technique are used in this work.The charge storage behaviour of the nanobelts is benchmarked against their binary metal oxide nanowires,i.e.,NiO and Co_(3)O_(4),as well as a hybrid of similar chemistry,CuO-Co_(3)O_(4).The nanobelts have thickness of~10 nm and width~200 nm,whereas the nanowires have diameter of~100 nm.Clear differences in charge storage behaviours are observed in NiO-Co_(3)O_(4) hybrid nanobelts based ASCs compared to those fabricated using the other materials-the former showed capacitive behav-iour whereas the others revealed battery-type discharge behaviour.Origin of pseudocapacitance in nanobelts based ASCs is shown to arise from their nanobelts morphology with thickness less than typical electron diffusion lengths(~20 nm).Among all the five type of devices fabricated,the NiO-Co_(3)O_(4) hybrid ASCs exhibited the highest specific energy,specific power and cycling stability.
基金funded by the Fundamental Research Grant Scheme of the Ministry of Education,Govt.of Malaysia through FRGS/1/2019/STG07/UMP/01/1(http://www.ump.edu.my)Battery Research Centre of Green Energy(BRCGE)of Ming Chi University of Technology,New Taipei,TaiwanTaiwan Experience Education Program(TEEP@AsiaPlus)for their research financial support.
文摘Electrode material has been cited as one of the most important determining factors in classifying an energy storage system’s charge storage mechanism,i.e.,as battery-type or supercapacitive-type.In this paper,we show that along with the electrode material,the electrolyte also plays a role in determining the charge storage behaviour of the system.For the purpose of our research,we chose multi-elemental spinal type CuMn_(2)O_(4) metal oxide nanofibers to prove the hypothesis.The material is synthesized as nanofibers of diameter~120 to 150 nm in large scales by a pilot scale electrospinning set up.It was then tested in three different electrolytes(1 M KOH,1 M Na_(2)SO_(4) and 1 M Li_(2)SO_(4)),two of which are neutral and the third is alkaline(KOH).The cyclic voltammograms and the galvanostatic charge-discharge of the electrode material in a three-electrode sys-tem measurement showed that it exhibit different charge storage mechanism in different electrolyte solutions.For the neutral electrolytes,a capacitive behaviour was observed whereas a battery-type behaviour was seen for the alkaline electrolyte.This leads us to conclude that the charge storage mechanism,along with the active material,also depends on the electrolyte used.
基金supported by UK EPSRC under grants EP/F023014/1 and EP/F000464/1a collaborative research fund from the Institute of Process Engineering of Chinese Academy of Sciences
文摘This short communication reports our recent work on the synthesis and characterisation ofmicrocapsules of phase change materials using silica as the shell material through a one-step method. The method uses no surfactants or dispersants for stabilising the capsules. The results show that the one-step method allows the tuning of the size and polydispersity of the capsules, and the use of different core materials. Analyses of the capsules show that they contain about 65% phase change materials. The results also suggest no need for a stabilising agent due to self-stabilisation by the amine groups. Further work is underway to investigate the mechanical and thermal properties of the microcapsules and the scale-up of the method.
基金the National 1000-Talents Programthe National Natural Science Foundation of China(Nos. 51773071, 51203067, 51603063)+1 种基金Wuhan Science and Technology Bureau(No. 2017010201010141)the Fundamental Research Funds for the Central Universities(No. HUST: 2017KFYXJJ023)for financial support
文摘Benefiting from the diversity and subjective design feasibility of molecular structure, flexibility,lightweight, molecular level controllability, resource renewability and relatively low cost, polymeric electrode materials are promising candidates for the next generation of sustainable energy resources and have attracted extensive attention for the foreseeable large scale applications. The conductive polymers have been utilized as electrode materials in the pioneer reports, which, however, have the disadvantages of low stability, low reversibility and slope voltage due to the delocalization of charges in the whole conjugated systems. The discovery of carbonyl materials aroused the interest of organic and polymeric materials for batteries again. This review presents the recent progress in carbonyl polymeric electrode materials for lithium-ion batteries, sodium-ion batteries and magnesium-ion batteries. This comprehensive review is expected to be helpful forarousing more interest of organic materials for met
基金This work was financially supported by“Hundred Young Talents Program”(No.263113491)from Guangdong University of Technology.
文摘With the increasing popularity of electric/hybrid vehicles and the rapid development of 3C electronics,there is a growing interest in high-rate energy storage systems.The rapid development and widespread adoption of lithiumion batteries(LIBs)can be attributed to their numerous advantages,including high energy density,high operating voltage,environmental friendliness,and lack of memory effect.However,the progress of LIBs is currently hindered by the limitations of energy storage materials,which serve as vital components.Therefore,there is an urgent need to address the development of a new generation of high-rate energy storage materials in order to overcome these limitations and further advance LIB technology.Niobium-based oxides have emerged as promising candidates for the fabrication of fast-charging Li-ion batteries due to their excellent rate capability and long lifespan.This review paper provides a comprehensive analysis of the fundamentals,methodologies,and electrochemistries of niobium-based oxides,with a specific focus on the evolution and creation of crystal phases of Nb_(2)O_(5),fundamental electrochemical behavior,and modification methods including morphology modulation,composite technology,and carbon coating.Furthermore,the review explores Nb_(2)O_(5)-derived compounds and related advanced characterization techniques.Finally,the challenges and issues in the development of niobiumbased oxides for high-rate energy storage batteries are discussed,along with future research perspectives.