Oxygen functionalization-assisted anionic exchange toward unique construction of flower-like transition metal chalcogenide embedded carbon fabric for ultra-long life flexible energy storage and conversion

The metal-organic framework(MOF)derived Ni–Co–C–N composite alloys(NiCCZ)were“embedded”inside the carbon cloth(CC)strands as opposed to the popular idea of growing them upward to realize ultrastable energy storage and conversion application.The NiCCZ was then oxygen functionalized,facilitating the next step of stoichiometric sulfur anion diffusion during hydrothermal sulfurization,generating a flower-like metal hydroxysulfide structure(NiCCZOS)with strong partial implantation inside CC.Thus obtained NiCCZOS shows an excellent capacity when tested as a supercapacitor electrode in a three-electrode configuration.Moreover,when paired with the biomass-derived nitrogen-rich activated carbon,the asymmetric supercapacitor device shows almost 100%capacity retention even after 45,000 charge–discharge cycles with remarkable energy density(59.4 Wh kg^(-1)/263.8μWh cm^(–2))owing to a uniquely designed cathode.Furthermore,the same electrode performed as an excellent bifunctional water-splitting electrocatalyst with an overpotential of 271 mV for oxygen evolution reaction(OER)and 168.4 mV for hydrogen evolution reaction(HER)at 10 mA cm−2 current density along with 30 h of unhinged chronopotentiometric stability performance for both HER and OER.Hence,a unique metal chalcogenide composite electrode/substrate configuration has been proposed as a highly stable electrode material for flexible energy storage and conversion applications.

Insight into structure evolution of carbon nitrides and its energy conversion as luminescence

A series of carbon nitride(CN)materials represented by graphitic carbon nitride(g-C_(3)N_(4))have been widely used in bioimaging,biosensing,and other fields in recent years due to their nontoxicity,low cost,and high luminescent quantum efficiency.What is more attractive is that the luminescent properties such as wavelength and intensity can be regulated by controlling the structure at the molecular level.Hence,it is time to summarize the related research on CN structural evolution and make a prospect on future developments.In this review,we first summarize the research history and multiple structural evolution of CN.Then,the progress of improving the luminescence performance of CN through structural evolution was discussed.Significantly,the relationship between CN structure evolution and energy conversion in the forms of photoluminescence,chemiluminescence,and electrochemiluminescence was reviewed.Finally,key challenges and opportunities such as nanoscale dispersion strategy,luminous efficiency improving methods,standardization evaluation,and macroscopic preparation of CN are highlighted.

Recent advances in core-shell organic framework-based photocatalysts for energy conversion and environmental remediation

Direct conversion of solar energy into chemical energy in an environmentally friendly manner is one of the most promising strategies to deal with the environmental pollution and energy crisis.Among a variety of materials developed as photocatalysts,the core-shell metal/covalent-organic framework(MOF or COF)photocatalysts have garnered significant attention due to their highly porous structure and the adjustability in both structure and functionality.The existing reviews on core-shell organic framework photocatalytic materials have mainly focused on core-shell MOF materials.However,there is still a lack of indepth reviews specifically addressing the photocatalytic performance of core-shell COFs and MOFs@COFs.Simultaneously,there is an urgent need for a comprehensive review encompassing these three types of core-shell structures.Based on this,this review aims to provide a comprehensive understanding and useful guidelines for the exploration of suitable core-shell organic framework photocatalysts towards appropriate photocatalytic energy conversion and environmental governance.Firstly,the classification,synthesis,formation mechanisms,and reasonable regulation of core-shell organic framework were summarized.Then,the photocatalytic applications of these three kinds of core-shell structures in different areas,such as H_(2)evolution,CO_(2)reduction,and pollutants degradation are emphasized.Finally,the main challenges and development prospects of core-shell organic framework photocatalysts were introduced.This review aims to provide insights into the development of a novel generation of efficient and stable core-shell organic framework materials for energy conversion and environmental remediation.

Electronic structure engineering of transition metal dichalcogenides for boosting hydrogen energy conversion electrocatalysts

Electrocatalytic water splitting for hydrogen production is an appealing strategy to reduce carbon emissions and generate renewable fuels.This promising process,however,is limited by its sluggish reaction kinetics and high-cost catalysts.The two-dimensional(2D)transition metal dichalcogenides(TMDCs)have presented great potential as electrocatalytic materials due to their tunable bandgaps,abundant defective active sites,and good chemical stability.Consequently,phase engineering,defect engineering and interface engineering have been adopted to manipulate the electronic structure of TMDCs for boosting their exceptional catalytic performance.Particularly,it is essential to clarify the local structure of catalytically active sites of TMDCs and their structural evolution in catalytic reactions using atomic resolution electron microscopy and the booming in situ technologies,which is beneficial for exploring the underlying reaction mechanism.In this review,the growth regulation,characterization,particularly atomic configurations of active sites in TMDCs are summarized.The significant role of electron microscopy in the understanding of the growth mechanism,the controlled synthesis and functional optimization of 2D TMDCs are discussed.This review will shed light on the design and synthesis of novel electrocatalysts with high performance,as well as prompt the application of advanced electron microscopy in the research of materials science.

Light-Material Interactions Using Laser and Flash Sources for Energy Conversion and Storage Applications

This review provides a comprehensive overview of the progress in light-material interactions(LMIs),focusing on lasers and flash lights for energy conversion and storage applications.We discuss intricate LMI parameters such as light sources,interaction time,and fluence to elucidate their importance in material processing.In addition,this study covers various light-induced photothermal and photochemical processes ranging from melting,crystallization,and ablation to doping and synthesis,which are essential for developing energy materials and devices.Finally,we present extensive energy conversion and storage applications demonstrated by LMI technologies,including energy harvesters,sensors,capacitors,and batteries.Despite the several challenges associated with LMIs,such as complex mechanisms,and high-degrees of freedom,we believe that substantial contributions and potential for the commercialization of future energy systems can be achieved by advancing optical technologies through comprehensive academic research and multidisciplinary collaborations.

Energy conversion due to non-ideal electric field in separatrix region of magnetotail reconnection

A recent satellite observation has revealed the presence of energy conversion in the separatrix region(SR)of magnetotail reconnection,driven by perpendicular components.We investigated this phenomenon by means of particle-in-cell simulations in two-dimensional(2D)and three-dimensional(3D)systems.Our result indicates that in the 2D simulation,energy conversion in the SR is dominated by parallel components,with the main influencing factor being the parallel electric field,which is not consistent with the observation.However,a case that is similar to the observation is found in the 3D simulation,suggesting that the observation result may be attributed to the 3D characteristics.Our findings provide a potential explanation for the satellite observation.

Cascade utilization of full spectrum solar energy for achieving simultaneous hydrogen production and all-day thermoelectric conversion

Solar-driven photocatalytic water/seawater splitting holds great potential for green hydrogen production.However,the practical application is hindered by the relatively low conversion efficiency resulting from the inadequate utilization of solar spectrum with significant waste in the form of heat.Moreover,current equipment struggles to maintain all-day operation subjected to the lack of light during nighttime.Herein,a novel hybrid system integrating photothermal catalytic(PTC)reactor,thermoelectric generator(TEG),and phase change materials(PCM)was proposed and designed(named as PTC-TEG-PCM)to address these challenges and enable simultaneous overall seawater splitting and 24-hour power generation.The PTC system effectively maintains in an optimal temperature range to maximize photothermal-assisted photocatalytic hydrogen production.The TEG component recycles the low-grade waste heat for power generation,complementing the shortcoming of photocatalytic conversion and achieving cascade utilization of full-spectrum solar energy.Furthermore,exceptional thermal storage capability of PCM allow for the conversion of released heat into electricity during nighttime,contributing significantly to the overall power output and enabling PTC-TEG-PCM to operate for more than 12 h under the actual condition.Compared to traditional PTC system,the overall energy conversion efficiency of the PTC-TEG-PCM system can be increased by∼500%,while maintaining the solar-to-hydrogen efficiency.The advancement of this novel system demonstrated that recycling waste heat from the PTC system and utilizing heat absorption/release capability of PCM for thermoelectric application are effective strategies to improve solar energy conversion.With flexible parameter designing,PTC-TEG-PCM can be applied in various scenarios,offering high efficiency,stability,and sustainability.

Novel high-entropy oxides for energy storage and conversion:From fundamentals to practical applications

High-entropy oxides(HEOs)are gaining prominence in the field of electrochemistry due to their distinctive structural characteristics,which give rise to their advanced stable and modifiable functional properties.This review presents fundamental preparations,incidental characterizations,and typical structures of HEOs.The prospective applications of HEOs in various electrochemical aspects of electrocatalysis and energy conversion-storage are also summarized,including recent developments and the general trend of HEO structure design in the catalysis containing oxygen evolution reaction(OER)and oxygen reduction reaction(ORR),supercapacitors(SC),lithium-ion batteries(LIBs),solid oxide fuel cells(SOFCs),and so forth.Moreover,this review notes some apparent challenges and multiple opportunities for the use of HEOs in the wide field of energy to further guide the development of practical applications.The influence of entropy is significant,and high-entropy oxides are expected to drive the improvement of energy science and technology in the near future.

Biomass Homogeneity Reinforced Carbon Aerogels Derived Functional Phase-Change Materials for Solar–Thermal Energy Conversion and Storage

We deviseda functional form stable compositephase-change materials(PCMs)toachieve a three-dimensional(3D)interconnectedporous carbon aerogel structure for encapsulating polyethyleneglycol(PEG).Anovelhomogeneity reinforced carbonaerogel witha well-interconnected porous structure was constructed bycombining a flexible carbonresource from biomass guar gum with hard-brittle carbonfrom polyimide,to overcome severeshrinkage andpoor mechanical performance of traditionalcarbon aerogel.Thesupportingcarbon aerogel-encapsulated PEG produced thenovel composite PCMswithgood structure stability andcomprehensive energy storage performance.Theresults showed thatthecomposite PCMsdisplayed awell-defined 3Dinterconnected structure,and theirenergy storage capacities were 171.5 and169.5 J/g,which changed onlyslightlyafter 100 thermalcycles,andthe compositescould maintainthe equilibrium temperature at50.0−58.1℃ for about 760.3 s.The thermal conductivityofthe compositescould reach0.62 W m^(−1) K^(−1),which effectively enhanced the thermalresponse rate.And thecomposite PCMs exhibited good leakage-proof performance andexcellent light–thermal conversion.The compressive strengthof thecomposite PCMscan improveupto 1.602 MPa.Results indicatethatthisstrategy canbe efficiently usedtodevelop novel composite PCMswithimproved comprehensive thermalperformance and high light–thermal conversion.

Oxidative Molecular Layer Deposition Tailoring Eco-Mimetic Nanoarchitecture to Manipulate Electromagnetic Attenuation and Self-Powered Energy Conversion

Advanced electromagnetic devices,as the pillars of the intelligent age,are setting off a grand transformation,redefining the structure of society to present pluralism and diversity.However,the bombardment of electromagnetic radiation on society is also increasingly serious along with the growing popularity of"Big Data".Herein,drawing wisdom and inspiration from nature,an eco-mimetic nanoarchitecture is constructed for the first time,highly integrating the advantages of multiple components and structures to exhibit excellent electromagnetic response.Its electromagnetic properties and internal energy conversion can be flexibly regulated by tailoring microstructure with oxidative molecular layer deposition(oMLD),providing a new cognition to frequency-selective microwave absorption.The optimal reflection loss reaches≈−58 dB,and the absorption frequency can be shifted from high frequency to low frequency by increasing the number of oMLD cycles.Meanwhile,a novel electromagnetic absorption surface is designed to enable ultra-wideband absorption,covering almost the entire K and Ka bands.More importantly,an ingenious self-powered device is constructed using the eco-mimetic nanoarchitecture,which can convert electromagnetic radiation into electric energy for recycling.This work offers a new insight into electromagnetic protection and waste energy recycling,presenting a broad application prospect in radar stealth,information communication,aerospace engineering,etc.

Carbon materials for enhanced photothermal conversion:Preparation and applications on steam generation

Photothermal conversion attracted lots of attention in the past years and sorts of materials were explored to enhance photothermal efficiency.In the past years,solar-driven desalination by photothermal conversion was proposed to release the shortage of fresh water and then it was considered much more important to prepare photothermal materials on large scales with high performance and low cost.In this review,we summarized the works on carbon-based photothermal materials in the past years,including the preparation as well as their application in steam generation.From these works,we give an outlook on the difficulties and chances of how to design and prepare carbon-based photothermal materials.

A Rising 2D Star:Novel MBenes with Excellent Performance in Energy Conversion and Storage

As a flourishing member of the two-dimen-sional(2D)nanomaterial family,MXenes have shown great potential in various research areas.In recent years,the continued growth of interest in MXene derivatives,2D transition metal borides(MBenes),has contributed to the emergence of this 2D material as a latecomer.Due to the excellent electrical conductivity,mechanical properties and electrical properties,thus MBenes attract more researchers’interest.Extensive experimental and theoretical studies have shown that they have exciting energy conversion and elec-trochemical storage potential.However,a comprehensive and systematic review of MBenes applications has not been available so far.For this reason,we present a comprehen-sive summary of recent advances in MBenes research.We started by summarizing the latest fabrication routes and excellent properties of MBenes.The focus will then turn to their exciting potential for energy storage and conversion.Finally,a brief summary of the challenges and opportunities for MBenes in future practical applications is presented.

Electrospun Semiconductor-Based Nano-Heterostructures for Photocatalytic Energy Conversion and Environmental Remediation:Opportunities and Challenges

Harvesting solar energy to drive the semiconductor photocatalysis offers a promising tactic to address ever-growing challenges of both energy shortage and environmental pollution.Design and synthesis of nano-heterostructure photocatalysts with controllable components and morphologies are the key factors for achieving highly efficient photocatalytic processes.Onedimensional(1D)semiconductor nanofibers produced by electrospinning possess a large ratio of length to diameter,high ratio of surface to volume,small grain sizes,and high porosity,which are ideally suited for photocatalytic reactions from the viewpoint of structure advantage.After the secondary treatment of these nanofibers through the solvothermal,gas reduction,in situ doping,or assembly methods,the multi-component nanofibers with hierarchical nano-heterostructures can be obtained to further enhance their light absorption and charge carrier separation during the photocatalytic processes.In recent years,the electrospun semiconductorbased nano-heterostructures have become a“hot topic”in the fields of photocatalytic energy conversion and environmental remediation.This review article summarizes the recent progress in electrospinning synthesis of various kinds of high-performance semiconductor-based nano-heterostructure photocatalysts for H2 production,CO_(2) reduction,and decomposition of pollutants.The future perspectives of these materials are also discussed.

Graphene-based electrocatalysts for advanced energy conversion

Graphene-based nanocatalysts have appealed much interest as advanced electrocatalysts toward energy conversion reactions due to their outstanding electrocatalytic performance from the distinctive chemical composites and strong synergistic effects.Aiming to better understand the role of graphene played in enhancing the catalytic performance and offer guidance for fabricating more efficient graphenebased electrocatalysts,we herein summarize the remarkable achievements of graphene-based electrocatalysts for energy-conversion-related reactions.Started by discussing applications of graphene in the electrocatalytic reactions,we have manifested the crucial role of graphene played in promoting the catalytic performance.Subsequently,many representative graphene-based catalyst hybrids for electrocatalytic reactions are also overviewed,showing many effective strategies for the fabrication of more efficient graphene-related materials for the practical application.Finally,the perspective insights and challenging issues are also concluded to provide directions for the future development.

Atomically dispersed metal sites in COF-based nanomaterials for electrochemical energy conversion

Atomically dispersed metal sites(ADMSs)play key roles in electrochemical energy conversion.The covalent organic frameworks(COFs)enable the precise control of the chemical compositions and structures at the molecular level,making them ideal substrates for supporting ADMSs.In this review,we systematically summarize the recent progress on the design and synthesis of ADMSs in COFs,including embedding molecular catalysts into COFs,immobilizing ADMSs on heteroatom-containing COFs,and preparing COF-derived carbon materials through pyrolysis.The electrocatalytic performance of the resulting catalysts is presented for various electrochemical reactions,involving oxygen reduction reaction(ORR),carbon dioxide reduction reaction(CO_(2)RR),oxygen evolution reaction(OER),hydrogen evolution reaction(HER),and nitrogen reduction reaction(NRR).The modulation strategies of AMDSs in COFs for enhanced activity,selectivity,and stability are highlighted,together with a perspective of the current challenges and the future opportunities in this field.

Meta-analysis of CO_(2) conversion,energy efficiency,and other performance data of plasma-catalysis reactors with the open access PIONEER database

This paper brings the comparison of performances of CO_(2)conversion by plasma and plasma-assisted catalysis based on the data collected from literature in this field,organised in an open access online database.This tool is open to all users to carry out their own analyses,but also to contributors who wish to add their data to the database in order to improve the relevance of the comparisons made,and ultimately to improve the efficiency of CO_(2)conversion by plasma-catalysis.The creation of this database and database user interface is motivated by the fact that plasma-catalysis is a fast-growing field for all CO_(2)conversion processes,be it methanation,dry reforming of methane,methanolisation,or others.As a result of this rapid increase,there is a need for a set of standard procedures to rigorously compare performances of different systems.However,this is currently not possible because the fundamental mechanisms of plasma-catalysis are still too poorly understood to define these standard procedures.Fortunately however,the accumulated data within the CO_(2)plasma-catalysis community has become large enough to warrant so-called“big data”studies more familiar in the fields of medicine and the social sciences.To enable comparisons between multiple data sets and make future research more effective,this work proposes the first database on CO_(2)conversion performances by plasma-catalysis open to the whole community.This database has been initiated in the framework of a H_(2)0_(2)0 European project and is called the“PIONEER Data Base”.The database gathers a large amount of CO_(2)conversion performance data such as conversion rate,energy efficiency,and selectivity for numerous plasma sources coupled with or without a catalyst.Each data set is associated with metadata describing the gas mixture,the plasma source,the nature of the catalyst,and the form of coupling with the plasma.Beyond the database itself,a data extraction tool with direct visualisation features or advanced filtering functionalities has been developed and is available online to the public.The simple and fast visualisation of the state of the art puts new results into context,identifies literal gaps in data,and consequently points towards promising research routes.More advanced data extraction illustrates the impact that the database can have in the understanding of plasma-catalyst coupling.Lessons learned from the review of a large amount of literature during the setup of the database lead to best practice advice to increase comparability between future CO_(2)plasma-catalytic studies.Finally,the community is strongly encouraged to contribute to the database not only to increase the visibility of their data but also the relevance of the comparisons allowed by this tool.

Evolution of cavity size and energy conversion due to droplet impact on a water surface

The deformation characteristics of the cavity due to droplet impact on a water surface are experimentally investigated.Dimensional analysis shows that the characteristic values of time,depth,and horizontal diameter can be taken as 10^(-3)times the ratio of surface tension to the product of viscosity coefficient and gravitational acceleration,the maximum depth,and the maximum horizontal diameter,respectively.The evolutions of the dimensionless cavity sizes for different values of Weber number(We)coincide for 220<We<686.A partial-sphere model of cavity is established based on experimental observations.Energy models are then derived,and the energy conversions are calculated to identify the relationship between these conversions and cavity deformation.It is found that the kinetic energy model established under the hypothesis proposed by Leng is no longer applicable when the dimensionless time t^(*)<3.5,owing to deviations from the geometric model.

Photoinduced Cu^(+)/Cu^(2+)interconversion for enhancing energy conversion and storage performances of CuO based Li-ion battery

Pursuing appropriate photo-active Li-ion storage materials and understanding their basic energy storage/conversion principle are pretty crucial for the rapidly developing photoassisted Li-ion batteries(PA-LIBs).Copper oxide(CuO)is one of the most popular candidates in both LIBs and photocatalysis.While CuO based PA-LIBs have never been reported yet.Herein,one-dimensional(1D)CuO nanowire arrays in situ grown on a three-dimensional(3D)copper foam support were employed as dualfunctional photoanode for both‘solar-to-electricity’and‘electricity-to-chemical’energy conversion in the PA-LIBs.It is found that light energy can be indeed stored and converted into electrical energy through the assembled CuO based PA-LIBs.Without external power source,the photo conversion efficiency of CuO based photocell reaches about 0.34%.Impressively,at a high current density of 4000 m A g^(-1),photoassisted discharge and charge specific capacity of CuO based PA-LIBs respectively receive 64.01%and 60.35%enhancement compared with the net electric charging and discharging process.Mechanism investigation reveals that photogenerated charges from CuO promote the interconversion between Cu^(2+)and Cu^(+)during the discharging/charging process,thus forcing the lithium storage reaction more completely and increasing the specific capacity of the PA-LIBs.This work can provide a general principle for the development of other high-efficient semiconductor-based PA-LIBs.

A review:Multi-hierarchy design strategy of electrocatalysts for energy molecule conversion

Under the new energy resource structure,electrocatalysts are key materials for the development of proton membrane fuel cells,electrolysis of aquatic hydrogen devices,and carbon dioxide reduction equipment,to address energy shortages and even environmental pollution issues.Although controlling the morphology or doping with heteroatoms for catalyst active centers have accelerated the reaction rate,it is difficult to solve the problems of multiple by-products,and poor stability of catalytic sites.From this,it will be seen that single regulation of metal active centers is difficult to comprehensively solve application problems.Orderly assembly and coordination of catalyst multi-hierarchy structures at the mesoscale above the nanometer level probably be more reasonable strategies,and numerous studies in thermal catalysis have supported this viewpoint.This article reviews the multi-hierarchy design of electrocatalyst active centers,high-energy supports,and peripheral structures in recent years,providing unconventional inspiration about electrocatalyst creation,which perhaps serves as a simple tutorial of electrocatalysis exploration for abecedarian.

The effect of the guide field on energy conversion during collisionless magnetic reconnection

Magnetic reconnection is well known as an efficient mechanism for transferring magnetic energy into plasma energy.However,how the energy conversion and partition between different species is influenced by the shear angle of the reconnecting magnetic component(i.e.,the guide field strength)is not well understood.Using 2.5-dimensional particle-in-cell simulations,we investigated the energy conversion in reconnection with different guide fields.We found that the overall energy conversion first decreases steeply and then increases slowly when the guide field increases fromB_(g)=0 toB_(g)=4.The increase in energy conversion in the large guide field regime is due to the electron energy gain through the perpendicular channelJ_(⊥)·E_(⊥).The overall energy conversion is predominantly contributed byJ_(⊥)·E_(⊥) rather thanJ||E||.We further find that energy conversion mainly occurs within the reconnection front and the flux pileup region.However,the contribution from the fore reconnection front becomes important in large guide field regimes(3<B_(g)≤4)because of the enhanced electron energy gain.