Department of Chemical Engineering, Waterloo Institute for Nanotechnology, Waterloo Institute for Sustainable Energy, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, N2L 3G1, Canada.
Angew Chem Int Ed Engl. 2016 Apr 11;55(16):4977-82. doi: 10.1002/anie.201600750. Epub 2016 Mar 11.
Rational design of highly active and durable electrocatalysts for oxygen reactions is critical for rechargeable metal-air batteries. Herein, we report the design and development of composite electrocatalysts based on transition metal oxide nanocrystals embedded in a nitrogen-doped, partially graphitized carbon framework. Benefiting from the unique pomegranate-like architecture, the composite catalysts possess abundant active sites, strong synergetic coupling, enhanced electron transfer, and high efficiencies in the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). The Co3O4-based composite electrocatalyst exhibited a high half-wave potential of 0.842 V for ORR, and a low overpotential of only 450 mV at the current density of 10 mA cm(-2) for OER. A single-cell zinc-air battery was also fabricated with superior durability, holding great promise in the practical implementation of rechargeable metal-air batteries.
用于氧反应的高效且耐用的电催化剂的合理设计对于可再充电金属空气电池至关重要。在此，我们报告了基于嵌入在氮掺杂、部分石墨化碳框架中的过渡金属氧化物纳米晶体的复合电催化剂的设计和开发。得益于独特的石榴状结构，该复合材料催化剂具有丰富的活性位点、强协同耦合、增强的电子转移以及在氧还原反应（ORR）和析氧反应（OER）中的高效率。基于 Co3O4 的复合电催化剂在 ORR 中表现出 0.842 V 的高半波电位，并且在 10 mA·cm-2 的电流密度下 OER 的过电位仅为 450 mV。还制备了具有优异耐久性的锌空气单电池，在可再充电金属空气电池的实际实施中具有很大的应用前景。
