A review:Modification strategies of nickel-rich layer structure cathode(Ni≥0.8)materials for lithium ion power batteries

Lithium ion power batteries have undoubtedly become one of the most promising rechargeable batteries at present;nonetheless,they still suffer from the challenges such as requirement of even higher energy density and capacity retention.Nickel-rich layer oxides(Ni≥0.8)become ideal cathode materials to achieve the high specific capacity.Integration of optimization of synthesis process and modification of crystal structure to suppress the capacity fading can obviously improve the performance of the lithium ion batteries.This review presents the recent modification strategies of the nickel-rich layered oxide materials.Unlike in previous reviews and related papers,the specific mechanism about each type of the modification strategies is specially discussed in detail,which is mainly about inhibiting the anisotropic lattice strain and adjusting the cation mixing degree to maintain crystal structure.Based on the recent progress,the prospects and challenges of the modified nickel-rich layer cathodes to upgrade the property of lithium ion batteries are also comprehensively analyzed,and the potential applications in the field of plug-in hybrid vehicles and electric vehicles are further discussed.

A review on heterogeneous photocatalysis for environmental remediation:From semiconductors to modification strategies

Heterogeneous photocatalysis,an advanced oxidation process,has garnered extensive attention in the field of environmental remediation because it involves the direct utilization of solar energy for the removal of numerous pollutants.However,the application of heterogeneous photocatalysis in environmental remediation has not achieved the expected consequences due to enormous challenges such as low photocatalytic efficiencies and high costs of heterogeneous photocatalysts in large-scale practical applications.Furthermore,pollutants in the natural environment,including water,air,and solid phases,are diverse and complex.Therefore,extensive efforts should be made to better understand and apply heterogeneous photocatalysis for environmental remediation.Herein,the fundamentals of heterogeneous photocatalysis for environmental remediation are introduced.Then,potential semiconductors and their modification strategies for environmental photocatalysis are systematically presented.Finally,conclusions and prospects are briefly summarized,and the direction for the future development of environmental photocatalysis is explored.This review may provide reference directions toward understanding,researching,and designing photocatalytic remediation systems for various environmental pollutants.

MXenes/CNTs-based hybrids:Fabrications,mechanisms,and modification strategies for energy and environmental applications

Emerging two-dimensional(2D)layered metal carbide and nitride materials,commonly termed MXenes,are increasingly recognized for their applications across diverse fields such as energy,environment,and catalysis.In the past few years,MXenes/carbon nanotubes(CNTs)-based hybrids have attracted extensive attention as an important catalyst in energy and environmental fields,due to their superior multifunctions and mechanical stability.This review aims to address the fabrication strategies,the identification of the enhancement mechanisms,and recent progress regarding the design and modification of MXenes/CNTs-based hybrids.A myriad of fabrication techniques have been systematically summarized,including mechanical mixing,spray drying,three-dimensional(3D)printing,self-assembly/in-situ growth,freeze drying,templating,hydrothermal methods,chemical vapor deposition(CVD),and rolling.Importantly,the identification of the enhancement mechanisms was thoroughly discussed from the two dimensions of theoretical simulations and in-situ analysis.Moreover,the recent advancements in profound applications of MXenes/CNTs-based hybrids have also been carefully revealed,including energy storage devices,sensors,water purification systems,and microwave absorption.We also underscore anticipated challenges related to their fabrication,structure,underlying mechanisms,modification approaches,and emergent applications.Consequently,this review offers insights into prospective directions and the future trajectory for these promising hybrids.It is expected that this review can inspire new ideas or provide new research methods for future studies.

Recent advances in modification strategies of silicon-based lithiumion batteries

As potential alternatives to graphite,silicon(Si)and silicon oxides(SiO_(x))received a lot of attention as anode materials for lithiumion batteries owing to their relatively low working potentials,high theoretical specific capacities,and abundant resources.However,the commercialization of Si-based anodes is greatly hindered by their massive volume expansion,low conductivity,unstable solid electrolyte interface(SEI),and low initial Coulombic efficiency(ICE).Continuous endeavors have been devoted to overcoming these challenges to achieve practical usage.This review is centered on the major challenges and latest developments in the modification strategies of Si-based anodes,including structure optimization,surface/interface regulation,novel binders,and innovative design of electrolyte.Finally,outlooks and perspectives of Si-based anodes for future development are presented.

The component-activity interrelationship of cobalt-based bifunctional electrocatalysts for overall water splitting:Strategies and performance

Cobalt-based electrocatalysts take advantage of potentially harmonizable microstructure and flexible coupling effects compared to commercial noble metal-based catalytic materials.However,conventional water electrolysis systems based on cobalt-based monofunctional hydrogen evolution reaction(HER)or oxygen evolution reaction(OER)catalysts have certain shortcomings in terms of resource utilization and universality.In contrast,cobalt-based bifunctional catalysts(CBCs)have attracted much attention in recent years for overall water splitting systems because of their practicality and reduced preparation cost of electrolyzer.This review aims to address the latest development in CBCs for total hydrolysis.The main modification strategies of CBCs are systematically classified in water electrolysis to provide an overview of how to regulate their morphology and electronic configuration.Then,the catalytic performance of CBCs in total-hydrolysis is summarized according to the types of cobalt-based phosphides,sulfides and oxides,and the mechanism of strengthened electrocatalytic ability is emphasized through combining experiments and theoretical calculations.Future efforts are finally suggested to focus on exploring the dynamic conversion of reaction intermediates and building near-industrial CBCs,designing advanced CBC materials through micro-modulation,and addressing commercial applications.

Modification strategies on 2D Ni-Fe MOF-based catalysts in peroxydisulfate activation for efficient organic pollutant removal

This study reports several modification strategies to optimize and enhance the performance of twodimensional(2D) metal organic frameworks(MOFs)-derived catalysts in peroxydisulfate(PDS) activation.The raw 2D Ni-MOF and 2D Ni-Fe-MOF without modification show poor catalytic activities for PDS activation and high metal ion leaching. The carbonization of 2D MOF can increase the activity of the catalyst but cannot solve the metal leaching problem. The further acid treatment of carbonization products can further improve the catalytic activity and decrease the metal ion leaching. The in-situ growth of2D MOF on graphene oxide(GO) support with subsequent carbonization and acid treatment offers the best performance in PDS activation for organic pollutant removal with low metal ion leaching. Compared with other PDS systems, the Ni-Fe-C-acid/GO system displays much lower catalyst and PDS dosages for p-chloroaniline degradation. This study presents new insights in the modification strategies of 2D MOFbased catalysts in PDS activation.

Recent progress in emerging BiPO_(4)-based photocatalysts:Synthesis,properties,modification strategies,and photocatalytic applications

In this perspective,we have highlighted the current literature and explained the synthesis,structure,morphology,modification strategies,and photocatalytic applications of emerging BiPO_(4)-based photocatalysts.Since BiPO_(4)is a large bandgap photocatalyst,it uses UV light for the excitation of electrons,and also,the recombination of charge carriers is an issue in BiPO_(4).Various novel modification strategies of BiPO_(4)photocatalysts viz.defect modifications,heterojunction formation,phase-junctions,surface plasmon resonance,Schottky junction have been successfully proposed and highlighted.These modifications enhance the light absorption and inhibit the recombination of charge carriers BiPO_(4)photocatalyst.Finally,future aspects for further research on BiPO_(4)-based photocatalysts are also explored.It expects that BiPO_(4)-based photocatalysts represent a promising strategy for developing practical photocatalysts for energy and environmental remediation applications.

Recent Progress on Modification Strategies of Alloy-based Anode Materials for Alkali-ion Batteries

Alkali-ion batteries,including lithium-ion batteries(LIBs),sodium-ion batteries(NIBs)and potassium-ion batteries(KIBs),with alloy-based anodes exhibit huge potential in high energy density due to the natural abundance,high theoretical capacity as well as suitable operating voltages.However,the practical application is severely hindered by the huge volume variation based on the alloying mechanism and inferior conductivity,especially for red phosphorus(P)and silicon(Si)anodes,which induces poor rate capability and fast capacity decay.Herein,we will briefly review fundamental advantages and challenges of alloy-based anode materials.Then,effective modification strategies of alloy-based anode materials for boosting the performance would be emphasized and discussed.Finally,we will share our perspectives and some opportunities to obtain high-performance alloy-based anode materials for further application.

Waste Mg alloys hydrogen production from seawater:An integrative overview of medium optimization,hydrogen-producing materials,underlying mechanisms,innovative technologies,and device development

In response to global carbon neutrality targets,there is an urgent need for large-scale,clean hydrogen production technologies to supplant fossil fuels and underpin the establishment of a‘hydrogen economy’.The prospect of large-scale on-site green hydrolysis of Mg-based materials for hydrogen production has attracted wide attention.Aiming at the problems of easy formation of inert oxide layer on its surface and the production of Mg(OH)_(2) to hinder the hydrolysis process,it is urgent to explore efficient,low-cost and green modification strategies.In this work,the green modification strategy for hydrolyzing hydrogen production of Mg-based materials was summarized,and the fast initial kinetics and high hydrogen production rate could be achieved by adjusting hydrolysis medium conditions and modifying Mg-based material.The significance of hydrolytic hydrogen production technology and device development for the realization of Mg-based hydrolytic hydrogen production was evaluated.Meanwhile,this work looks forward to the future direction of hydrogen production modification by hydrolysis of Mg-based alloy,and gradually optimizes the hydrolysis performance of industrial multi-component waste Mg alloy under the premise of green hydrogen production,and proposes the goal of efficient modification of waste Mg alloy,high-quality utilization of seawater,and low-cost and controllable hydrogen production process.

Shifting Rule Modification Strategy of Automatic Transmission Based on Driver-vehicle-road Environment

Accidental or frequent shift often occurs when the shifting rule is built based on traditional two parameters （i.e., velocity and throttle）, because the speed of engine varies slower than change of throttle opening. Currently, modifying shift point velocity value or throttle by throttle change rate is one of common methods, but the results are not so satisfactory in some working condition such as uphill. The reason is that these methods merely consider throttle change rate which is not enough for a car driving in driver-vehicle-road environment system. So a novel fuzzy control modification strategy is proposed to avoid or reduce those abnormal shift actions. It can adjust shifting rule by the change rate of throttle, current gear position and road environment information, while different gear position and driving environment get corresponding modification value. In order to compare the results of shifting actions, fuel consumption and braking distance, emergent braking in level road and extra-urban driving cycle（EUDC） working conditions with fuzzy shifting schedule modification strategy are simulated digitally. Furthermore, a hardware-in-the-loop simulation platform is introduced to verify its effect in slope road condition according to the ON/OFF numbers of solenoid valve in hydraulic system. The simulation results show that the problem of unexpected shift in those working conditions may be resolved by fuzzy modification strategy. At last, it is concluded that although there is some slight decline in power performance in uphill situation, this fuzzy modification strategy could correctly identify slope of road, decrease braking distance, improve vehicle comfort and fuel economy effectively and prolong the life of clutch system. So, this fuzzy logic shifting strategy provides important references for vehicle intelligent shifting schedule.

Typical strategies to facilitate charge transfer for enhanced oxygen evolution reaction: Case studies on hematite

Hydrogen can be sustainably produced through photoelectrochemical(PEC)water splitting.The process of PEC water splitting is composed of two vital half-reactions:water oxidation to O2 on photoanode,and proton reduction to H2 on photocathode.Both in thermodynamics and kinetics,the oxidation of water on photoanode is much more challenging,because the formation of O2 involves the four-holes reaction process that is more difficult than the two-protons reduction.Accordingly,the oxidation of water into O2 is the rate-determining reaction for PEC water splitting,which is closely affected by the light harvesting,charge separation and transfer,as well as surface activity of photoanode.In principle,water oxidation is initiated by the photo-excited charge of photoanode.In this review,we took hematite photoanode as a typical example to illustrate the progress in modifying the charge separation and migration property of metal-oxide photoanodes for water oxidation.The typical strategies adopted to facilitate the charge transfer and separation of hematite photoanode were specifically summarized.In addition,the views designing and developing hematite photoanode with high-performance for water oxidation were presented.This review provides comprehensive information about the state-of-the-art progress of hematite-based photoanodes and forecast the developing directions of photoanode materials for solar water splitting.

Engineering versatile Au-based catalysts for solar-to-fuel conversion

Gold(Au) nanostructures(NSs) have been widely employed as cocatalysts to improve the photoactivity of semiconductor materials, while a systematic summary of the engineering approaches of Au NSs to maximize the solar-to-fuel conversion efficiency is still lacking. In this review, the recently developed strategies for elevating the overall photocatalytic performance of Au-based catalysts and the deep physical chemistry mechanisms are highlighted. Firstly, the synthetic approaches of Au NSs are summarized, followed by an elaboration on their multiple functions in improving photoactivity. Afterward, modification strategies of Au NSs used to enhance the photocatalytic efficiency of Au-semiconductor composites,including controlling the Au NSs morphology, size, crystal phase, defect engineering, alloying with different metals, modulating interfacial interaction, and introducing an external field, are summarized and discussed independently. Additionally, advanced characterization techniques that can provide insights into the charge dynamics of the photocatalysts are introduced. Finally, we share our opinion on the challenges and outline potentially promising opportunities and directions for efficient Au-based photocatalysis research moving forward. We sincerely look forward to this review can deliver insightful views to design efficient Au-based photocatalysts and spur certain innovations to other metal-based catalysts.

Rational design of MoS_(2)-based catalysts toward lignin hydrodeoxygenation:Interplay of structure,catalysis,and stability

The MoS_(2)-based materials are a vital class of heterogeneous catalysts for the hydrodeoxygenation of lignin and its model compounds to produce value-added chemicals especially because of their unique selectivity to aromatics.The rational design of MoS_(2)-based catalyst greatly depends on the comprehensive understanding of its structure-activity relationship.However,an intensive summary and critical analysis are still scarce to date.In this review,we attempt to provide an in-depth understanding of the interplay of structure,catalysis,and stability of MoS_(2)-based catalysts for lignin hydrodeoxygenation.The recognition of intrinsic active sites on MoS_(2) structure was firstly discussed,followed by the illustration of MoS_(2)-catalyzed hydrodeoxygenation structural models.Afterward,based on the studies on the MoS_(2)-catalyzed lignin model compounds hydrodeoxygenation,the current active site modification strategies including structural modification of monometallic MoS_(2) catalysts and collaborative modification were summarized and emphatically discussed,which aims to elucidate the structure-activity relationship at the atomic-level.The deactivation mechanism and stabilization strategies were also illustrated to provide instructive suggestion for the rational design of efficient and stable MoS_(2)-based catalysts.Finally,the real lignin depolymerization over MoS_(2)-based catalysts was summarized to point out the advantages and difficulties.This review attempts to highlight the remaining challenges and provide some perspectives for the future development of MoS_(2)-based catalysts for lignin hydrodeoxygenation.

Photocatalytic applications and modification methods of two-dimensional nanomaterials:a review

Due to its unique electronic structure and special size effect,two-dimensional(2D)nanomaterials have shown great potential far beyond bulk materials in the field of photocatalysis.How to deeply explore the photocatalytic mechanism of 2D nanomaterials and design more efficient 2D semiconductor photocatalysts are research hotspots.This review provides a comprehensive introduction to typical 2D nanomaterials and discusses their current application status in the field of photocatalysis.The effects of material properties such as band structure,morphology,crystal face structure,crystal structure and surface defects on the photocatalytic process are discussed.The main modification methods are highlighted,including doping,noble metal deposition,heterojunction,thickness adjustment,defect engineering,and dye sensitization in 2D material systems.Finally,the future development of 2D nanomaterials is prospected.It is hoped that this paper can provide systematic and useful information for researchers engaged in the field of photocatalysis.

Stress accumulation in Ni-rich layered oxide cathodes:Origin,impact,and resolution

LiNi_(x)Co_(y)Mn_(z)O_(2)(NCM,x+y+z=1)is one of the most promising cathode candidates for high energy density lithium-ion batteries(LIBs).Due to the potential in enhancing energy density and cyclic life of LIBs,Ni-rich layered NCM(NCM,x≥0.6)have garnered significant research attention.However,improved specific capacity lead to severer expansion and shrinkage of layered lattice,accelerating the stress generation and accumulation even microcracks formation in NCM materials.The microcracks can promote the electrolyte permeation and decomposition,which can consequently reduce cyclic stabilities.Therefore,it is significant to provide an in-depth insight into the origin and impacts of stress accumulation,and the available modification strategies for the future development of NCM materials.In this review,we will first summarize the origin of stress accumulation in NCM materials.Next,we discuss the impact of stress accumulation.The electrolyte permeation along microcracks can enhance the extent of side reaction at the interface,trigger phase transformation and consequential capacity fading.To cushion the impact of stress accumulation,we will review five main strategies.Finally,concise perspectives to reduce stress accumulation and enhance particle strength in further works will be presented.

Advanced nanoengineering strategies endow highperformance layered transition-metal oxide cathodes for sodium-ion batteries

Considering the abundance and low price of sodium,sodium-ion batteries(SIBs)have shown great potential as an alternative to existing lithium-based batteries in large-scale energy storage systems,including electric automobiles and smart grids.Cathode materials,which largely decide the cost and the electrochemical performance of the full SIBs,have been extensively studied.Among the reported cathodes,layered transition-metal oxides(LTMOs)are regarded as the most extremely promising candidates for the commercial application of the SIBs owing to their high specific capacity,superior redox potential,and suitable scalable preparation.Nevertheless,irreversible structural evolution,sluggish kinetics,and water sensitivity are still the critical bottlenecks for their practical utilization.Nanoengineering may offer an opportunity to address the above issues by increasing reactivity,shortening diffusion pathways,and strengthening structural stability.Herein,a comprehensive summary of the modification strategies for LTMOs is presented,emphasizing optimizing the structure,restraining detrimental phase transition,and promoting diffusion kinetics.This review intends to facilitate an in-depth understanding of structure-composition-property correlation and offer guidance to the further development of the LTMO cathodes for next-generation energy storage systems.

Solid polymer electrolytes:Ion conduction mechanisms and enhancement strategies

Solid polymer electrolytes(SPEs)possess comprehensive advantages such as high flexibility,low interfacial resistance with the electrodes,excellent film-forming ability,and low price,however,their applications in solid-state batteries are mainly hindered by the insufficient ionic conductivity especially below the melting temperatures,etc.To improve the ion conduction capability and other properties,a variety of modification strategies have been exploited.In this review article,we scrutinize the structure characteristics and the ion transfer behaviors of the SPEs(and their composites)and then disclose the ion conduction mechanisms.The ion transport involves the ion hopping and the polymer segmental motion,and the improvement in the ionic conductivity is mainly attributed to the increase of the concentration and mobility of the charge carriers and the construction of fast-ion pathways.Furthermore,the recent advances on the modification strategies of the SPEs to enhance the ion conduction from copolymer structure design to lithium salt exploitation,additive engineering,and electrolyte micromorphology adjustion are summarized.This article intends to give a comprehensive,systemic,and profound understanding of the ion conduction and enhancement mechanisms of the SPEs for their viable applications in solid-state batteries with high safety and energy density.

Manipulating metal-support interactions of metal catalysts for Fischer-Tropsch synthesis

For supported metal catalyst systems,the impact on catalysis originates from the interaction between metal nanoparticles and their support.Metal-support interactions(MSI)can change electronic properties,geometric morphologies,or chemical compositions of metal nanoparticles to make active sites have specific properties and catalytic activities.Fischer-Tropsch synthesis(FTS)is one of the most effective ways to convert cheap non-petroleum-based carbon sources into high value-added chemicals or ultraclean liquid fuels.In this review,we summarize and classify the impact of MSI on the catalytic activity,selectivity and stability of FTS catalysts.The strategies to tune MSI are introduced in detail,and the recent development of high-efficiency FTS catalysts through the manipulation of SMI strategies has been highlighted.It is emphasized that the active metal sites,which are endowed with special functions by MSI,can change the strength of adsorption bond of adsorbates,consequently controlling the product distribution.

Sustained release of exosomes loaded into polydopamine-modified chitin conduits promotes peripheral nerve regeneration in rats

Exosomes derived from mesenchymal stem cells are of therapeutic interest because of their important role in intracellular communication and biological regulation.On the basis of previously studied nerve conduits,we designed a polydopamine-modified chitin conduit loaded with mesenchymal stem cell-derived exosomes that release the exosomes in a sustained and stable manner.In vitro experiments revealed that rat mesenchymal stem cell-derived exosomes enhanced Schwann cell proliferation and secretion of neurotrophic and growth factors,increased the expression of Jun and Sox2 genes,decreased the expression of Mbp and Krox20 genes in Schwann cells,and reprogrammed Schwann cells to a repair phenotype.Furthermore,mesenchymal stem cell-derived exosomes promoted neurite growth of dorsal root ganglia.The polydopamine-modified chitin conduits loaded with mesenchymal stem cell-derived exosomes were used to bridge 2 mm rat sciatic nerve defects.Sustained release of exosomes greatly accelerated nerve healing and improved nerve function.These findings confirm that sustained release of mesenchymal stem cell-derived exosomes loaded into polydopamine-modified chitin conduits promotes the functional recovery of injured peripheral nerves.

A hybrid chemical modification strategy for monocrystalline silicon micro-grinding:Experimental investigation and synergistic mechanism

For high performance manufacturing of micro parts and features,a hybrid chemical modification strategy is proposed to decrease critical energy barrier of mechanical removal of hard and brittle crystal material by refining localized machining condition.The strategy,namely UVlight and IR-laser hybrid chemical modification(UVIR-CM)strategy,includes two steps,an ultraviolet light(UV-light)catalytic advanced oxidation and an infrared laser(IR-laser)assisted selective modification based on Fenton liquid–solid reaction for monocrystalline silicon.The modification effects of UVIR-CM strategy were investigated by surface morphology micro-observation,crosssection transmission electron microscopy(TEM)observation,Raman spectroscopy analysis and nanoindentation test.Experimental results demonstrated that varied degrees of laser texturing appeared on different strategy samples’IR-laser scanned area.And the IR-laser thermal damage has been successfully inhibited due to the refraction and reflection of energy by bubbles in liquid medium.But for the UVIR-CM strategy,a uniform and amorphous silicate layer is detected in a certain boundary.The UV-light promotes oxidation cycle ability of the chemical solution and ensures sufficient oxide modified layer for subsequent step.Attributing to synergism of photochemical,photothermal and kinetic effects induced by IR-laser,the modified layer displays layered structure with about 600 nm thickness,(2.7±0.60)GPa nanohardness,and(93.7±22.9)GPa indentation modulus.And the layered structure is amorphous layer,nanocrystal and micro-twins layer from the surface to the interior of sample.Consequently,it reveals that the subsequent mechanical removal will become easy due to decreasing energy barrier of monocrystalline silicon in selective area.Meanwhile,its original excellent mechanical properties also are maintained under a certain depth.The results contribute to develop a novel combined micro-machining technology to achieve collaborative manufacturing of structure shape and surface integrity for micro parts and feature.