Catalytic effect in lithium metal batteries: From heterogeneous catalyst to homogenous catalyst

Lithium metal batteries are regarded as prominent contenders to address the pressing needs owing to the high theoretical capacity.Toward the broader implementation,the primary obstacle lies in the intricate multi-electron,multi-step redox reaction associated with sluggish conversion kinetics,subsequently giving rise to a cascade of parasitic issues.In order to smooth reaction kinetics,catalysts are widely introduced to accelerate reaction rate via modulating the energy barrier.Over past decades,a large amount of research has been devoted to the catalyst design and catalytic mechanism exploration,and thus the great progress in electrochemical performance has been realized.Therefore,it is necessary to make a comprehensive review toward key progress in catalyst design and future development pathway.In this review,the basic mechanism of lithium metal batteries is provided along with corresponding advantages and existing challenges detailly described.The main catalysts employed to accelerate cathode reaction with emphasis on their catalytic mechanism are summarized as well.Finally,the rational design and innovative direction toward efficient catalysts are suggested for future application in metal-sulfur/gas battery and beyond.This review is expected to drive and benefit future research on rational catalyst design with multi-parameter synergistic impacts on the activity and stability of next-generation metal battery,thus opening new avenue for sustainable solution to climate change,energy and environmental issues,and the potential industrial economy.

Two positive effects with one arrow:Modulating crystal and interfacial decoration towards high-potential cathode material

As the primary suppliers of cyclable sodium ions,O3-type layer-structured manganese-based oxides are recognized as highly competitive cathode candidates for sodium-ion batteries.To advance the development of high-energy sodium-ion batteries,it is crucial to explore cathode materials operating at high voltages while maintaining a stable cycling behavior.The orbital and electronic structure of the octahedral center metal element plays a crucial role in maintaining the octahedra structural integrity and improving Na^(+)ion diffusion by introducing heterogeneous chemical bonding.Inspired by the abundant configuration of extra nuclear electrons and large ion radius,we employed trace amounts of tungsten in this study.The obtained cathode material can promote the reversibility of oxygen redox reactions in the high-voltage region and inhibit the loss of lattice oxygen.Additionally,the formation of a Na_(2)WO_(4) coating on the material surface can improve the interfacial stability and interface ions diffusion.It demonstrates an initial Coulombic efficiency(ICE)of 94.6%along with 168.5 mA h g^(-1 )discharge capacity within the voltage range of 1.9-4.35 V.These findings contribute to the advancement of high-energy sodium-ion batteries by providing insights into the benefits of tungsten doping and Na_(2)WO_(4) coating on cathode materials.

Boosting nitrogen electrocatalytic fixation by three-dimensional TiO_(2-δ)N_δnanowire arrays

Owing to the environmental and inherent advantages,nitrogen reduction reaction(NRR)by electrocatalysts attracts global attention.The surface engineering is widely employed to enhance the electrocatalytic activity by atomic defects and heterostructure effects.A three-dimensional(3D)free-standing integrated electrode was fabricated by numerous nearly-single-crystal TiO_(2-δ)N_δnanowire arrays.Based on the high electronic conductivity network,it exposes numerous active sites as well to facilitate the selective nitrogen adsorption and*H adsorption suppression.The synergistic effects between Ti^(3+)and oxygen vacancy(O_v)boost the intrinsic catalytic activity,in which Ti^(3+)acquired electrons via Ovcan effectively activate the N≡N bond and make it easy to bind with protons.The energy barrier of primary protonation process(*N_(2)+H^(+)+e^(-)→*NNH)can be dramatically decreased.The highest ammonia yield rate(14.33μg h^(-1)mgcat^(-1))emerges at-0.2 V,while the optimal ammonia Faradaic efficiency(9.17%)is acquired at-0.1 V.Density functional theory(DFT)calculation reveals that the Ti^(3+)can be served as the active sites for nitrogen adsorption and activation,while ammonia synthesis is accomplished by the distal pathway.The high electronic conductivity integrated network and synergistic effects can significantly facilitate nitrogen absorption and accelerate electrocatalytic reaction kinetic,which are responsible for the excellent NRR performance at room temperature.

Realizing a dendrite-free metallic-potassium anode using reactive prewetting chemistry

Potassium metal batteries(PMBs)have become a paramount alternative energy storage technology to lithium-ion batteries,due to their low cost and potential energy density.However,uncontrolled dendrite growth interferes with the stability of the interfacial anode,leading to significant capacity degradation and safety hazards.Herein,a facile reactive prewetting strategy is proposed to discourage dendrite growth by constructing a functional KF/Znrich hybrid interface layer on K metal.The KF/Zn@K anode design functions like an interconnected paddy field,stabilizing the anode interface through the preferential redistribution of Kþflux/electrons,continuous transport paths,and enhanced transport dynamics.As anticipated,symmetrical batteries exhibit an extended cycling lifetime of over 2000 h,with reduced voltage hysteresis at 0.5 mA cm^(-2) and 0.5 mAh cm^(-2).Furthermore,when the KF/Zn@K anode is applied to full batteries coupled with PTCDA,a boosted reversible capacity of 61.6 mAh g1 at 5 C is present over 3000 cycles.This interfacial control creates rational possibilities for constructing highefficiency,stable K metal anodes.

Regulating ion transport behaviors toward dendrite-free potassium metal batteries:recent advances and perspectives

With abundant potassium resources and high capacity,potassium metal batteries(PMBs)present a compelling option for the next generation of energy storage technology.However,PMBs suffer from an unstable anode interface caused by uncontrolled dendrite growth,which results in unsatisfactory cyclability and safety concerns.Extensive investigations suggest that significant progress has been made in enhancing the interfacial stability of PMBs.The various effective strategies for stabilizing interfaces can ultimately be attributed to the regulation of the sluggish ion transfer kinetics and irregular deposition,i.e.,the arrangement of ion transport behaviors at the interface.Rational modulation of ions transport rate and ions deposition directions makes it possible to obtain a dendrite-free and smooth deposition plane.Herein,the influencing factors and action mechanism of K^(+)interface transport behaviors are discussed to understand the nature of material design for constructing stable anode interfaces,including regulating the solvation and desolvation structures,accelerating K^(+)transport kinetics and controlling K^(+)deposition direction.In addition,the deficiencies and prospects of the research on electrolyte,separators and designed electrode involved in the manufacturing and testing and ion transport process of PMBs are discussed.This review is expected to provide some possible directions for constructing dendrite-free interfaces in advanced PMBs-related research and offer significant insights for prospective experimental research and commercial applications.