The use of carbon-based particle electrodes in three-dimensional electrode reactors for wastewater treatment

The use of three-dimensional(3D)electrodes in water treatment is competitive because of their high catalytic efficiency,low energy consumption and promising development.The use of particle electrodes is a key research focus in this technology.They are usually in the form of particles that fill the space between the cathode and anode,and the selection of materials used is important.Carbon-based materials are widely used because of their large specific surface area,good adsorption performance,high chemical stability and low cost.The principles of 3D electrode technology are introduced and recent research on its use for degrading organic pollutants using carbon-based particle electrodes is summarized.The classification of particle electrodes is introduced and the challenges for the future development of carbon-based particle electrodes in wastewater treatment are discussed.

A Mini Review on Nanocarbon-Based 1D Macroscopic Fibers:Assembly Strategies and Mechanical Properties

Nanocarbon-based materials, such as carbon nanotubes(CNTs) and graphene have been attached much attention by scientific and industrial community. As two representative nanocarbon materials, one-dimensional CNTs and twodimensional graphene both possess remarkable mechanical properties. In the past years, a large amount of work have been done by using CNTs or graphene as building blocks for constructing novel, macroscopic, mechanically strong fibrous materials. In this review, we summarize the assembly approaches of CNT-based fibers and graphene-based fibers in chronological order, respectively. The mechanical performances of these fibrous materials are compared, and the critical influences on the mechanical properties are discussed. Personal perspectives on the fabrication methods of CNT-and graphene-based fibers are further presented.

Carbon-based nanomaterials cause toxicity by oxidative stress to the liver and brain in Sprague-Dawley rats

Carbon-based nanomaterials have important research significance in various disciplines,such as composite materials,nanoelectronic devices,biosensors,biological imaging,and drug delivery.Recently,the human and ecological risks associated with carbon-based nanomaterials have received increasing attention.However,the biological safety of carbon based nanomaterials has not been systematically studied.In this study,we used different types of carbon materials,namely,graphene oxide(GO),single-walled carbon nanotubes(SWCNTs),and multiwalled carbon nanotubes(MWCNTs),as models to observe their distribution and oxidative damage in vivo.The results of Histopathological and ultrastructural examinations indicated that the liver and lungs were the main accumulation targets of these nanomaterials.SR-μ-XRF analysis revealed that SWCNTs and MWCNTs might be present in the brain.This shows that the three types of carbon-based nanomaterials could cross the gas-blood barrier and eventually reach the liver tissue.In addition,SWCNTs and MWCNTs could cross the blood-brain barrier and accumulate in the cerebral cortex.The increase in ROS and MDA levels and the decrease in GSH,SOD,and CAT levels indicated that the three types of nanomaterials might cause oxidative stress in the liver.This suggests that direct instillation of these carbon-based nanomaterials into rats could induce ROS generation.In addition,iron(Fe)contaminants in these nanomaterials were a definite source of free radicals.However,these nanomaterials did not cause obvious damage to the rat brain tissue.The deposition of selenoprotein in the rat brain was found to be related to oxidative stress and Fe deficiency.This information may support the development of secure and reasonable applications of the studied carbon-based nanomaterials.

Improvement in Performance of Carbon-based Perovskite Solar Cells through Interface Modification with CTAC

Carbon-based perovskite solar cells have attracted much attention,due to their low cost,simple preparation process and high chemical stability.However,the devices exhibit low photoelectric conversion efficiency,owing to the presence of defects and interface impedance between the perovskite active layer and the contact interface.In order to minimize the interfacial defects and improve the charge transfer performance between the perovskite layer and the contact interface,cetyltrimethylammonium chloride(CTAC)was introduced into the lower interface of HTL-free carbon-based perovskite solar cells,because CTAC can be used as interface modification material to passivate the buried interface of perovskite and promote grain growth.It was found that CTAC can not only passivate the interface defects of perovskite,but also improve the crystalline quality of perovskite.As a result,the photovoltaic conversion efficiency of reaches 17.18%,which is 12.5%higher than that of the control group.After 20 days in air with 60%RH humidity,the cell can still maintain more than 90%of the initial efficiency,which provides a new strategy for interfacial passivation of perovskite solar cells.

“Zero‑Strain” NiNb_(2)O_(6) Fibers for All‑Climate Lithium Storage

Niobates are promising all-climate Li^(+)-storage anode material due to their fast charge transport,large specific capacities,and resistance to electrolyte reaction.However,their moderate unit-cellvolume expansion(generally 5%–10%)during Li^(+)storage causes unsatisfactory long-term cyclability.Here,“zero-strain”NiNb_(2)O_(6) fibers are explored as a new anode material with comprehensively good electrochemical properties.During Li^(+)storage,the expansion of electrochemical inactive NiO_(6) octahedra almost fully offsets the shrinkage of active NbO_(6) octahedra through reversible O movement.Such superior volume-accommodation capability of the NiO_(6) layers guarantees the“zero-strain”behavior of NiNb_(2)O_(6) in a broad temperature range(0.53%//0.51%//0.74%at 25//−10//60℃),leading to the excellent cyclability of the NiNb_(2)O_(6) fibers(92.8%//99.2%//91.1%capacity retention after 1000//2000//1000 cycles at 10C and 25//−10//60℃).This NiNb_(2)O_(6) material further exhibits a large reversible capacity(300//184//318 mAh g−1 at 0.1C and 25//−10//60℃)and outstanding rate performance(10 to 0.5C capacity percentage of 64.3%//50.0%//65.4%at 25//−10//60℃).Therefore,the NiNb_(2)O_(6) fibers are especially suitable for large-capacity,fast-charging,long-life,and all-climate lithium-ion batteries.

Carbon-based derivatives from metal-organic frameworks as cathode hosts for Li–S batteries

Lithium-sulfur batteries(Li–S batteries) are promising candidates for the next generation high-energy rechargeable Li batteries due to their high theoretical specific capacity(1672 m Ahg-1) and energy density(2500 Wh kg-1). The commercialization of Li–S batteries is impeded by several key challenges at cathode side, e.g. the insulating nature of sulfur and discharged products(Li2S 2 and Li2S), the solubility of long-chain polysulfides and volume variation of sulfur cathode upon cycling. Recently, the carbonbased derivatives from metal-organic frameworks(MOFs) has emerged talent in their utilization as cathode hosts for Li–S batteries. They are not only highly conductive and porous to enable the acceleration of Li +/e-transfer and accommodation of volumetric expansion of sulfur cathode during cycling, but also enriched by controllable chemical active sites to enable the adsorption of polysulfides and promotion of their conversion reaction kinetics. In this review, based on the types of MOFs(e.g. ZIF-8, ZIF-67, Prussian blue, Al-MOF, MOF-5, Cu-MOF, Ni-MOF), the synthetic methods, formation process and morphology, structural superiority of MOFs-derived carbon frameworks along with their electrochemical performance as cathode host in Li–S batteries are summarized and discussed.

Carbon-Based MOF Derivatives:Emerging Efficient Electromagnetic Wave Absorption Agents

To tackle the aggravating electromagnetic wave(EMW)pollution issues,high-efficiency EMW absorption materials are urgently explored.Metal-organic framework(MOF)derivatives have been intensively investigated for EMW absorption due to the distinctive components and structures,which is expected to satisfy diverse application requirements.The extensive developments on MOF derivatives demonstrate its significantly important role in this research area.Particularly,MOF derivatives deliver huge performance superiorities in light weight,broad bandwidth,and robust loss capacity,which are attributed to the outstanding impedance matching,multiple attenuation mechanisms,and destructive interference effect.Herein,we summarized the relevant theories and evaluation methods,and categorized the state-of-the-art research progresses on MOF derivatives in EMW absorption field.In spite of lots of challenges to face,MOF derivatives have illuminated infinite potentials for further development as EMW absorption materials.

Multifunctional roles of carbon-based hosts for Li-metal anodes:A review

With its high theoretical capacity,lithium(Li)metal is recognized as the most potential anode for realizing a high-performance energy storage system.A series of questions(severe safety hazard,low Coulombic efficiency,short lifetime,etc.)induced by uncontrollable dendrites growth,unstable solid electrolyte interface layer,and large volume change,make practical application of Li-metal anodes still a threshold.Due to their highly appealing properties,carbon-based materials as hosts to composite with Li metal have been passionately investigated for improving the performance of Li-metal batteries.This review displays an overview of the critical role of carbon-based hosts for improving the comprehensive performance of Li-metal anodes.Based on correlated mainstream models,the main failure mechanism of Li-metal anodes is introduced.The advantages and strategies of carbon-based hosts to address the corresponding challenges are generalized.The unique function,existing limitation,and recent research progress of key carbon-based host materials for Li-metal anodes are reviewed.Finally,a conclusion and an outlook for future research of carbon-based hosts are presented.This review is dedicated to summarizing the advances of carbon-based materials hosts in recent years and providing a reference for the further development of carbonbased hosts for advanced Li-metal anodes.

Reaction Kinetics of Biodiesel Synthesis from Waste Oil Using a Carbon-based Solid Acid Catalyst

The kinetics of simultaneous transesterification and esterification with a carbon-based solid acid catalyst was studied.Two solid acid catalysts were prepared by the sulfonation of carbonized vegetable oil asphalt and petroleum asphalt.These catalysts were characterized on the basis of elemental analysis,acidity site concentration,the Brunauer-Emmett-Teller（BET）surface area and pore size.The kinetic parameters with the two catalysts were determined,and the reaction system can be described as a pseudo homogeneous catalyzed reaction.All the forward and reverse reactions follow second order kinetics.The calculated concentration values from the kinetic equations are in good agreement with experimental values.

Structure and denitration performance of carbon-based catalysts prepared from Cu-BTC precursor

Using Cu-BTC prepared by hydrothermal method as precursor, carbon-based catalysts were obtained as model materials for low-temperature DeNO_x. These catalysts were characterized by X-ray diffractometry（XRD）, Raman spectroscopy, scanning electron microscopy（SEM） and energy dispersive X-ray spectrometry（EDS）. The results showed that all carbon-based catalysts held the octahedron shape of Cu-BTC in most parts, and they mainly consisted of face-centered cubic copper. CuO_x/C exhibited excellent catalytic activity, and such catalytic activity was further improved with the introduction of Ag. The catalyst with a Cu to Ag mole ratio of 6：1 and an activated temperature of 600 °C showed the best catalytic performance, and its catalytic denitration rate reached 100% at a temperature as low as 235 °C. During the catalytic reaction process, Cu~＋ mainly played a catalytic role.

Carbon-Based Flexible and All-Solid-State Micro-supercapacitors Fabricated by Inkjet Printing with Enhanced Performance

By means of inkjet printing technique, flexible and all-solid-state micro-supercapacitors(MSCs) were fabricated with carbon-based hybrid ink composed of graphene oxide(GO,98.0vol.%) ink and commercial pen ink(2.0vol.%). A small amount of commercial pen ink was added to effectively reduce the agglomeration of theGO sheets during solvent evaporation and the following reduction processes in which the presence of graphite carbon nanoparticles served as nano-spacer to separate GO sheets. The printed device fabricated using the hybrid ink,combined with the binder-free microelectrodes and interdigital microelectrode configuration, exhibits nearly 780%enhancement in areal capacitance compared with that of pure GO ink. It also shows excellent flexibility and cycling stability with nearly 100% retention of the areal capacitance after 10,000 cycles. The all-solid-state device can be optionally connected in series or in parallel to meet the voltage and capacity requirements for a given application.This work demonstrates a promising future of the carbonbased hybrid ink for directly large-scale inkjet printing MSCs for disposable energy storage devices.

Wet carbon-based solid acid/NaNO_3 as a mild and efficient reagent for nitration of aromatic compound under solvent free conditions

Nitro aromatic compound can be obtained in high yields via nitration of aromatic compound with wet carbon-based solid acid and NaNO_3 under solvent free oxidation at room temperature.

Composition Optimization and Microstructure Design in MOFs-Derived Magnetic Carbon-Based Microwave Absorbers:A Review

Magnetic carbon-based composites are the most attractive candidates for electromagnetic(EM)absorption because they can terminate the propagation of surplus EM waves in space by interacting with both electric and magnetic branches.Metal-organic frameworks(MOFs)have demonstrated their great potential as sacrificing precursors of magnetic metals/carbon composites,because they provide a good platform to achieve high dispersion of magnetic nanoparticles in carbon matrix.Nevertheless,the chemical composition and microstructure of these composites are always highly dependent on their precursors and cannot promise an optimal EM state favorable for EM absorption,which more or less discount the superiority of MOFs-derived strategy.It is hence of great importance to develop some accompanied methods that can regulate EM properties of MOFs-derived magnetic carbon-based composites e ectively.This review comprehensively introduces recent advancements on EM absorption enhancement in MOFs-derived magnetic carbon-based composites and some available strategies therein.In addition,some challenges and prospects are also proposed to indicate the pending issues on performance breakthrough and mechanism exploration in the related field.

Advances in colored carbon-based fiber materials and their emerging applications

Carbon-based fiber materials are widely used in aerospace,military,and electronics owing to their outstanding comprehensive properties.However,the high degree of crystallization and chemical inertness of their surfaces impede the coloring of such materials by traditional dyeing methods,thereby limiting their application in a broader field.Exploring advanced micro/nano-processing technology for colored carbon-based fiber materials has become a growing interdisciplinary research area in recent years.Therefore,this review comprehensively discusses the structure‒color‒function relationships of carbon-based fiber materials.The structure of carbon-based fiber materials and their properties responsible for challenges in coloring by traditional dyeing methods are discussed.Moreover,the color-generating mechanisms underlying the display of structural colors by living organisms due to fundamental optical phenomena,including thin/multilayer-film interference,diffraction grating,scattering,and photonic crystals,are described.Furthermore,recent progress in bio-inspirated colored carbon-based fiber materials prepared via advanced micro/nanoscale manufacturing strategies is reviewed.In addition,emerging applications of colored carbon-based fiber materials in various fields are presented.Finally,the possible challenges and future directions for the design,large-scale production,and application of colored carbon-based fibermaterials and their composites are discussed,aiming to promote the material design of innovative next-generation systems and research in the advanced material and related engineering fields.

Wet carbon-based solid acid/potassium permanganate as an efficient heterogeneous reagents for oxidation of alcohols under mild conditions

Wet carbon-based solid acid and potassium permanganate were used as new reagents for oxidation of alcohols to their corresponding aldehydes and ketones in heterogeneous mixtures. The experiments were done moderately at mild condition and high yields in suitable times were obtained.

Photo-rechargeable batteries and supercapacitors:Critical roles of carbon-based functional materials

As a clean and renewable energy source,solar energy is a competitive alternative to replace conventional fossil fuels.Nevertheless,its serious fluctuating nature usually leads to a poor alignment with the actual energy demand.To solve this problem,the direct solar-to-electrochemical energy conversion and storage have been regarded as a feasible strategy.In this context,the development of high-performance integrated devices based on solar energy conversion parts(i.e.,solar cells or photoelectrodes)and electrochemical energy storage units(i.e.,rechargeable batteries or supercapacitors[SCs])has become increasingly necessary and urgent,in which carbon and carbon-based functional materials play a fundamental role in determining their energy conversion/storage performances.Herein,we summarize the latest progress on these integrated devices for solar electricity energy conversion and storage,with special emphasis on the critical role of carbon-based functional materials.First,principles of integrated devices are introduced,especially roles of carbon-based materials in these hybrid energy devices.Then,two major types of important integrated devices,including photovoltaic and photoelectrochemicalrechargeable batteries or SCs,are discussed in detail.Finally,key challenges and opportunities in the future development are also discussed.By this review,we hope to pave an avenue toward the development of stable and efficient devices for solar energy conversion and storage.

Strigolactones modulate cotton fiber elongation and secondary cell wall thickening

Cotton is one of the most important economic crops in the world,and it is a major source of fiber in the textile industry.Strigolactones(SLs)are a class of carotenoid-derived plant hormones involved in many processes of plant growth and development,although the functions of SL in fiber development remain largely unknown.Here,we found that the endogenous SLs were significantly higher in fibers at 20 days post-anthesis(DPA).Exogenous SLs significantly increased fiber length and cell wall thickness.Furthermore,we cloned three key SL biosynthetic genes,namely GhD27,GhMAX3,and GhMAX4,which were highly expressed in fibers,and subcellular localization analyses revealed that GhD27,GhMAX3,and GhMAX4 were localized in the chloroplast.The exogenous expression of GhD27,GhMAX3,and GhMAX4 complemented the physiological phenotypes of d27,max3,and max4 mutations in Arabidopsis,respectively.Knockdown of GhD27,GhMAX3,and GhMAX4 in cotton resulted in increased numbers of axillary buds and leaves,reduced fiber length,and significantly reduced fiber thickness.These findings revealed that SLs participate in plant growth,fiber elongation,and secondary cell wall formation in cotton.These results provide new and effective genetic resources for improving cotton fiber yield and plant architecture.

Recent Advances in Carbon-Based Current Col lectors/Hosts for Alkali Metal Anodes

The urgent demand for high-energy-density storage systems evokes the research upsurge on the alkali metal batteries with high theoretical capacities.However,the utilization of alkali metal anodes,including Li,Na,and K,is significantly hindered by notorious dendrite growth,undesirable corrosion,and unstable solid electrolyte interface.In order to resolve these issues,the carbon materials for the rational design of current collector/host that can regulate the plating/stripping behavior of alkali metal have been exploited.These carbon-based current collectors/hosts are featured with many pivotal advantages,including mechanical integrity to accommodate the volume change,superior electronic/ionic conductivity,large available surface area,and rich functionalization chemistries to increase the affinity to alkali metal.In this review,the recent progress on various dimensional carbon-based current collectors/hosts with different chemical components in stabilizing the alkali metal anodes through the regulation of initial deposition and subsequent growth behavior during plating/stripping process is provided.The nanostructured carbon scaffolds with self-affinity to alkali metals,as well as the carbon frameworks with internal/external affinitive sites to alkali metals,catalogued by various dimensions,are discussed in this review.Therefore,these appealing strategies based on the carbon-based current collectors/hosts can provide a paradigm for the realization of high-energy-density alkali metal batteries.

Long-Chain Gemini Surfactant-Assisted Blade Coating Enables Large-Area Carbon-Based Perovskite Solar Modules with Record Performance

Carbon-based perovskite solar cells show great potential owing to their low-cost production and superior stability in ambient air.However,scaling up to high-efficiency carbon-based solar modules hinges on reliable deposition of uniform defect-free perovskite films over large areas,which is an unsettled but urgent issue.In this work,a long-chain gemini surfactant is introduced into perovskite precursor ink to enforce self-assembly into a network structure,considerably enhancing the coverage and smoothness of the perovskite films.The long gemini surfactant plays a distinctively synergistic role in perovskite film construction,crystallization kinetics modulation and defect passivation,leading to a certified record power conversion efficiency of 15.46%with Voc of 1.13 V and Jsc of 22.92 mA cm^(-2)for this type of modules.Importantly,all of the functional layers of the module are printed through a simple and high-speed(300 cm min^(-1))blade coating strategy in ambient atmosphere.These results mark a significant step toward the commercialization of all-printable carbon-based perovskite solar modules.

Enhancing the cycling stability of Na-ion batteries by bonding MoS2 on assembled carbon-based materials

Room temperature Na-ion batteries(SIBs) show great potential for use as renewable energy storage systems.However, the large-scale application of SIBs has been hindered by the lack of an ideal SIBs anode material. We synthesized MoS2 on carbonized graphene-chitosan(G-C) using the hydrothermal method. The strong interaction between the MoS2 and the G-C greatly improved the electron transport rate and maintained the structural stability of the electrode, which lead to both an excellent rate capability and long cycle stability. The G-C monolith was proven to enhance the electrical conductivity of the composites and served as a matrix for uniformly dispersing active MoS2 nanosheets(NSs), as well as being a buffer material to adapt to changes in volume during the cycle.Serving as an anode material for SIBs, the MoS2-G-C electrode showed good cycling stability(527.3mAh g-1 at100 m A g-1 after 200 cycles), excellent rate capability, and a long cycle life(439.1 m Ah g-1 at 1 A g-1 after 200 cycles).