Single-atom Catalysts for Polymer Electrolyte Membrane Fuel Cells

Searching for high-activity,stabilily and highly casbellective electrocalalysts for acid oxygen reaction rolutioo(ORR)has always been a urgent problem in polymer ectrolyte menbrane fuel ells(PEMFC).Nonetheless,the electrochemical poperties of various systems have their intrinsic limits and tremendous eforts have been paid oul to search for highly eficient electocatalysts by more raional control over the size,morphology,compoition,and structure.In particular,single-atom catalysts(SACs)have atrascted extensive intenest due to theirs cxcellant activity,stability,slctivity and the highest metal tiliztion In rceat yeurs,the number of papers in the field of SACs has incressed rapidly,indicating that SACs have made great progress.This review foouses on SACs electo-echemical applications in the acid ORR and introduces immovative syntheses,fiuel cell performance and long-time durabilily.

A Supported Palladium on Gallium-based Liquid Metal Catalyst for Enhanced Oxygen Reduction Reaction

Developing high-performance catalysts for oxygen reduction reaction to replace costly platinum-based materials is of great importance but still confronted with challenges.Herein,a kind of supported palladium liquid metal catalyst,which is prepared by galvanic replacement,surpasses commercial Pt/C and Pd/C in oxygen reduction catalysis with a higher half-wave potential of 0.92 V,mass activity of 1.85 A/mgPd at 0.90 V,and superior durability.The liquid metal support can both optimize the electronic structures of Pd sites and guarantee the dispersion of Pd atoms,which explains the enhanced activity and durability,respectively.This work opens an avenue for rational design of catalysts.

Special Issue of Single-atom Catalysis

Single-atom catalysts(SACs)are a new type of heterogeneous catalysts formed by isolated metal atoms anchored on kinds of substrates.SACs are distinctly distinguished from traditional catalysts by characterizing with unique electronic structure,quantum size effect and unsaturated coordination environment,etc.,which brought subverted effects on traditional catalytic fields once upon the emergence.The unique chemical and physical properties impart SACs with outstanding catalytic performance,embodying nearly 1o0%atom utilization,high catalytic activity and excellent durability.SACs invariably have been the"hotspot"in catalysis research field during the last decade,shining brilliantly in applications of electro-,photo-and thermal catalysis.In particular,the advent of SACs points towards a possibility of the substantial cost reduction of precious metal catalysts in the future.This themed issue selected advanced studies on design,synthesis,characterization,and application of SACs,dedicating to assisting readers in a comprehensively and in-depth understanding of SACs.