Formation of Ni-Fe mixed diselenide nanocages as a superior oxygen evolution electrocatalyst

• Main Authors: Nai, Jianwei, Lu, Yan, Yu, Le, Wang, Xin, Lou, David Xiong Wen
• Other Authors: School of Chemical and Biomedical Engineering
• Format: Article
• Language: English
• Published: 2020
• Subjects: Engineering::Chemical engineering; Diselenides; Electrocatalysis
• Online Access: https://hdl.handle.net/10356/139800
• Institution: Nanyang Technological University

Exploring effective electrocatalysts is a crucial requirement for boosting the efficiency of water splitting to obtain clean fuels. Here, a self-templating strategy is reported to synthesize Ni-Fe mixed diselenide cubic nanocages for the electrocatalytic oxygen evolution reaction (OER). The diselenide nanocages are derived from corresponding Prussian-blue analog nanocages, which are first obtained by treating the nanocube precursor with a site-selective ammonia etchant. The resulting Ni-Fe mixed diselenide nanocages perform as a superior OER electrocatalyst, which affords a current density of 10 mA cm-2 at a small overpotential of 240 mV; a high current density, mass activity, and turnover frequency of 100 mA cm-2 , 1000 A g-1 , and 0.58 s-1 , respectively, at the overpotential of 270 mV; a Tafel slope as small as 24 mV dec-1 ; and excellent stability in alkaline medium.