Recent progress and perspective on electrocatalysis in neutral media:Mechanisms,materials,and advanced characterizations

Electrocatalysis,which involves oxidation and reduction reactions with direct electron transfer,is essential for a variety of clean energy conversion devices.Currently,the vast majority of studies regarding electrocatalysis reactions focus on strong acidic or alkaline media because of the higher catalytic activity.Nevertheless,some inherent drawbacks,including the corrosive environment,expensive proton exchange membranes,and side effects,are still hard to break through.A sustainably promising way to overcome these shortcomings is to deploy neutral/near-neutral electrolytes for electrocatalysis reactions.Unfortunately,insufficient research in this area due to the lack of attention to related issues has slowed down the development process.In this review,we systematically review the catalytic reaction mechanisms,neutral electrolytes,electrocatalysts,and modification strategies carried out in neutral media on the three most common electrocatalytic reactions,that is,hydrogen evolution reaction,oxygen reduction reaction,and oxygen evolution reaction.Furthermore,the advanced characterization tools for guiding catalyst synthesis and mechanistic studies are also summarized.Eventually,we propose some challenges and perspectives on electrocatalysis reactions in neutral media and hope it will attract more research interest and provide guidance in neutral electrocatalysis.

A review of hard carbon anode: Rational design and advanced characterization in potassium ion batteries

K-ion batteries(KIBs)have attracted tremendous attention and seen significant development because of their low price,high operating voltage,and properties similar to those of Li-ion batteries.In the field of development of full batteries,exploring high-performing and low-cost anode materials for K-ion storage is a crucial challenge.Owing to their excellent cost effectiveness,abundant precursors,and environmental benignancy,hard carbons(HCs)are considered promising anode materials for KIBs.As a result,researchers have devoted much effort to quantify the properties and to understand the underlying mechanisms of HC-based anodes.In this review,we mainly introduce the electrochemical reaction mechanism of HCs in KIBs,and summarize approaches to further improve the electrochemical performance in HC-based materials for K-ion storage.In addition,we also highlight some advanced in situ characterization methods for understanding the evolutionary process underlying the potassiation–depotassiation process,which is essential for the directional electrochemical performance optimization of KIBs.Finally,we raise some challenges in developing smart-structured HC anode materials for KIBs,and propose rational design principles and perspectives serving as the guidance for the targeted optimization of HC-based KIBs.

Intrinsic Self-Healing Chemistry for Next-Generation Flexible Energy Storage Devices

The booming wearable/portable electronic devices industry has stimulated the progress of supporting flexible energy storage devices.Excellent performance of flexible devices not only requires the component units of each device to maintain the original performance under external forces,but also demands the overall device to be flexible in response to external fields.However,flexible energy storage devices inevitably occur mechanical damages(extrusion,impact,vibration)/electrical damages(overcharge,over-discharge,external short circuit)during longterm complex deformation conditions,causing serious performance degradation and safety risks.Inspired by the healing phenomenon of nature,endowing energy storage devices with self-healing capability has become a promising strategy to effectively improve the durability and functionality of devices.Herein,this review systematically summarizes the latest progress in intrinsic self-healing chemistry for energy storage devices.Firstly,the main intrinsic self-healing mechanism is introduced.Then,the research situation of electrodes,electrolytes,artificial interface layers and integrated devices based on intrinsic self-healing and advanced characterization technology is reviewed.Finally,the current challenges and perspective are provided.We believe this critical review will contribute to the development of intrinsic self-healing chemistry in the flexible energy storage field.

Artisanal ceramic factories using wood combustion:A nanoparticles and human health study

The ceramics industry,resulting from developments of modern compounds,is a segment of great influence in worldwide sustainability.Artisanal ceramic factories based on wood combustion have significant risks for the creation and discharge of atmosphere nanoparticles(NPs)and ultra-fine particles(UFPs).At present,there is insufficient recognition on the influence of engineered-NPs on the atmosphere and health.Real improvements are indispensable to diminish contact with NPs.The present study demonstrates the main NPs and UFPS present in an area of intense artisanal wood-combustion ceramic manufacturing.Particulate matter was sampled for morphological,chemical,and geochemical studies by sophisticated electron microbeam microscopy,X-Ray Diffraction,and Raman spectroscopy.From NPs configuration(<10 nm)we identify nucleation.Several amorphous NPs(>10 nm)were produced around the studied artisanal ceramic factories.This study presents an indication of the recent information on population and work-related contact to NPs in the artisanal ceramic factories and their influence on health.

Precise synthesis of dual atom sites for electrocatalysis

Single atom sites are widely applied in various electrocatalytic fields due to high atom utilization, mass activity, and selectivity. They are limited in catalyzing multi-electron reactions due to their intrinsic mono-metal center feature. Dual atom sites (DASs) as promising candidate have received enormous attentions because adjacent active sites can accelerate their catalytic performance via synergistic effect. Herein, the fundamental understandings and intrinsic mechanism underlying DASs and corresponding electrocatalytic applications are systemically summarized. Different synergy dual sites are presented to disclose the structure-performance relationship with engineering the well-defined DASs on the basis of theoretical principle. An overview of the electrocatalytic applications is showed, including oxygen reduction reaction, hydrogen evolution reaction, oxygen evolution reaction, carbon dioxide reduction reaction, and nitrogen reduction reaction. Finally, a conclusion and future prospective are provided to reveal the current challenges for rational designing, synthesizing, and modulating the advanced DASs toward electrocatalytic reactions.

Understanding and unveiling the electro-chemo-mechanical behavior in solid-state batteries

Solid-state batteries(SSBs)are attracting growing interest as long-lasting,thermally resilient,and high-safe energy storage systems.As an emerging area of battery chemistry,there are many issues with SSBs,including strongly reductive lithium anodes,oxidized cathodes(state of charge),the thermodynamic stability limits of solid-state electrolytes(SSEs),and the ubiquitous and critical interfaces.In this Review,we provided an overview of the main obstacles in the development of SSBs,such as the lithium anode|SSEs interface,the cathode|SSEs interface,lithium-ion transport in the SSEs,and the root origin of lithium intrusions,as well as the safety issues caused by the dendrites.Understanding and overcoming these obstacles are crucial but also extremely challenging as the localized and buried nature of the intimate contact between electrode and SSEs makes direct detection difficult.We reviewed advanced characterization techniques and discussed the complex ion/electron-transport mechanism that have been plaguing electrochemists.Finally,we focused on studying and revealing the coupled electro-chemo-mechanical behavior occurring in the lithium anode,cathode,SSEs,and beyond.

Graphene-supported metal single-atom catalysts:a concise review

Single-atom catalysts(SACs)have become an emerging frontier trend in the field of heterogeneous catalysis due to their high activity,selectivity and stability.SACs could greatly increase the availabilities of the active metal atoms in many catalytic reactions by reducing the size to single atom scale.Graphene-supported metal SACs have also drawn considerable attention due to the unique lattice structure and physicochemical properties of graphene,resulting in superior activity and selectivity for several chemical reactions.In this paper,we review recent progress in the fabrications,advanced characterization tools and advantages of graphene-supported metal SACs,focusing on their applications in catalytic reactions such as CO oxidation,the oxidation of benzene to phenol,hydrogen evolution reaction,methanol oxidation reaction,oxygen reduction reaction,hydrogenation and photoelectrocatalysis.We also propose the development of SACs towards industrialization in the future.

Multiscale understanding of high-energy cathodes in solid-state batteries: from atomic scale to macroscopic scale

In the crucial area of sustainable energy storage,solid-state batteries(SSBs)with nonflammable solid electrolytes stand out due to their potential benefits of enhanced safety,energy density,and cycle life.However,the complexity within the composite cathode determines that fabricating an ideal electrode needs to link chemistry(atomic scale),materials(microscopic/mesoscopic scale),and electrode system(macroscopic scale).Therefore,understanding solid-state composite cathodes covering multiple scales is of vital importance for the development of practical SSBs.In this review,the challenges and basic knowledge of composite cathodes from the atomic scale to the macroscopic scale in SSBs are outlined with a special focus on the interfacial structure,charge transport,and mechanical degradation.Based on these dilemmas,emerging strategies to design a high-performance composite cathode and advanced characterization techniques are summarized.Moreover,future perspectives toward composite cathodes are discussed,aiming to facilitate the develop energy-dense SSBs.

Evaluation of solid electrolytes: Development of conventional and interdisciplinary approaches

Solid-state lithium batteries(SSLBs)have received considerable attention due to their advantages in thermal stability,energy density,and safety.Solid electrolyte(SE)is a key component in developing high-performance SSLBs.An in-depth understanding of the intrinsic bulk and interfacial properties is imperative to achieve SEs with competitive performance.This review first introduces the traditional electrochemical approaches to evaluating the fundamental parameters of SEs,including the ionic and electronic conductivities,activation barrier,electrochemical stability,and diffusion coefficient.After that,the characterization techniques to evaluate the structural and chemical stability of SEs are reviewed.Further,emerging interdisciplinary visualization techniques for SEs and interfaces are highlighted,including synchrotron X-ray tomography,ultrasonic scanning imaging,time-of-flight secondary-ion mass spectrometry,and three-dimensional stress mapping,which improve the understanding of electrochemical performance and failure mechanisms.In addition,the application of machine learning to accelerate the screening and development of novel SEs is introduced.This review article aims to provide an overview of advanced characterization from a broad physical chemistry view,inspiring innovative and interdisciplinary studies in solid-state batteries.

Reviving Low-Temperature Performance of Lithium Batteries by Emerging Electrolyte Systems

Although lithium batteries have been successfully commercialized in the past two decades,they are particularly sensitive to ultralow temperatures.For most batteries,capacities and powers are lost at sub-zero temperatures,mainly due to the increased electrolyte viscosity,insufficient ionic conduction,slow charge-transfer kinetics,and reduced ion diffusing constant.In this review,we sorted out the critical factors leading to the poor low-temperature performance of electrolytes,and the comprehensive research progress of emerging electrolyte systems for the ultra-low temperature lithium battery is classified and highlighted.We further provide a systematic summary of the advanced characterization and computational simulation for low-temperature electrolyte systems to guide researchers in screening the low-temperature electrolytes,monitoring solvation/desolvation behavior,and investigating reaction mechanisms.Besides their fundamental significance,our review might also forge a new opportunity and prospects in the effective design of electrolytes for the ultralow temperature application of energy storage devices.

Progress in niobium-based oxides as anode for fast-charging Li-ion batteries

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.

Doping Strategy in Nickel-Rich Layered Oxide Cathode for Lithium-Ion Battery

Ni-rich layered oxides have been regarded as the most promising cathode material for next-generation high energy density Li-ion batteries because of their advantages in capacity and cost.However,these cathodes suffer from irreversible structural degradation,fast capacity attenuation as well as seriously reduced safety in their practical applications.Doping strategies with different elements have been employed to address the above issues.In this review,we summarize the research advances of the elemental doping in a Ni-rich layered oxide cathode.The experimental methods and dopant selection rules are briefly introduced.Then we discuss here the effects of the elemental doping from the aspects of the crystal lattice,electronic structure,nanomorphology,and surface stability.In addition,this review surveys the first-principles calculation and advanced structural characterization techniques,which have played important roles in elucidating the structure-performance correlations.Finally,perspectives regarding the future of doping strategy are given.