Unveiling Trifunctional Active Sites of a Heteronanosheet Electrocatalyst for Integrated Cascade Battery/Electrolyzer Systems
mediaposted on 11.06.2021, 13:38 by Xiaotong Han, Nannan Li, Ying Bo Kang, Qingyun Dou, Peixun Xiong, Qing Liu, Jin Yong Lee, Liming Dai, Ho Seok Park
Herein, we identify the unique trifunctional active sites of ReS2 and NiFe layered double hydroxide (NiFe-LDH) heteronanosheets (ReS2/NiFe-LDH) for integrated cascade Zn–air battery/electrolyzer systems. Along with the edge and surface sites of NiFe-LDH for both oxygen evolution reaction and oxygen reduction reaction activities, the unprecedented activity of the ReS2/NiFe-LDH heteronanosheets for the hydrogen evolution reaction emerges from the S–O bonds at the heterointerfaces, together with the strong coupling effect and vertical alignment of NiFe-LDH and ReS2. The outstanding trifunctional activities and a well understood mechanism ensure the use of ReS2/NiFe-LDH heteronanosheets for the development of integrated cascade battery/electrolyzer systems, in which electricity storage in the battery mode and H2 production in the electrolyzer mode are efficiently switched with high round-trip efficiency (61%) and Faraday efficiency (96%). The systems show great promise for cost-effective energy storage and H2 production applications ranging from the distribution in households to the assembly for electrical vehicles.