Clusters Induced Electron Redistribution to Tune Oxygen Reduction Activity of Transition Metal Single‐Atom for Metal–Air Batteries

Abstract

Oxygen reduction reaction (ORR) activity can be effectively tuned by modulating the electron configuration and optimizing the chemical bonds. Herein, a general strategy to optimize the activity of metal single‐atoms is achieved by the decoration of metal clusters via a coating–pyrolysis–etching route. In this unique structure, the metal clusters are able to induce electron redistribution and modulate M−N species bond lengths. As a result, M‐ACSA@NC exhibits superior ORR activity compared with the nanoparticle‐decorated counterparts. The performance enhancement is attributed to the optimized intermediates desorption benefiting from the unique electronic configuration. Theoretical analysis reinforces the significant roles of metal clusters by correlating the ORR activity with cluster‐induced charge transfer. As a proof‐of‐concept, various metal–air batteries assembled with Fe‐ACSA@NC deliver remarkable power densities and capacities. This strategy is an effective and universal technique for electron modulation of M−N−C, which shows great potential in application of energy storage devices.

Rapid complete reconfiguration induced actual active species for industrial hydrogen evolution reaction

“…However, they usually suffer from scarcity, high cost, and long-term instability 10 – 12 . Thus far, transition metal-based materials have turned to be the promising alternatives to noble metal catalysts because of their lower cost and appropriate electronic structure 13 , 14 . It is reported that they are prone to involving surface reconfiguration processes through electrochemical activation under complex conditions of catalytic reactions, ultimately exhibiting excellent catalytic performance 15 – 17 .…”

Manipulating the electronic configuration of Fe–N4sites by an electron-withdrawing/donating strategy with improved oxygen electroreduction performance

“…41 According to the above results, B-doping can induce more electron-accumulation in Fe-N 4 sites, which is expected to reduce the binding energy between Fe centers and oxygen intermediates. 42 To verify this conjecture, the temperatureprogrammed desorption of O 2 (O 2 -TPD) was measured. The electrons can transfer to chemisorbed oxygen from catalysts because of the electron affinity of oxygen, so it needs a high temperature for desorption.…”

Hierarchical Ni(OH)2–MnO2hollow spheres as an electrode material for high-performance supercapacitors

“…Recently, structure engineering with component optimization has become an effective strategy to boost the performance of electrode materials. 11,12 Hollow structures are highly suitable for use in supercapacitors in view of their considerable advantages, such as their large cavities, large surface areas, abundant ion-transmission paths and their ability to lessen volume variations. 13,14 Ni(OH) 2 is a candidate electrode material for supercapacitors that has received much attention as it combines a high theoretical specific capacitance and strong chemical redox activity.…”