posted on 2022-01-14, 14:05authored bySangmin Jeong, Hien Duy Mai, Ki-Hun Nam, Cheol-Min Park, Ki-Joon Jeon
Electrocatalysts
with dramatically enhanced water splitting efficiency,
derived from controlled structures, phase transitions, functional
activation, etc., have been developed recently. Herein,
we report an in situ observation of graphene-based
self-healing, in which this functional activation is induced by a
redox reaction. Specifically, graphene on stainless steel (SUS) switches
between graphene (C–C) and graphene oxide (C–O) coordination
via an electrical redox reaction to activate water splitting. A heterostructure
comprising Pt-NiO thin films on single-layer graphene directly grown
on a SUS substrate (Pt-NiO/Gr-SUS) was also synthesized by electrodeposition.
Pt-NiO/Gr-SUS exhibited water splitting activity with low Pt loading
(<1 wt %). The findings provide valuable insight for designing
robust electrodes based on reversible redox-induced self-healable
graphene to develop more efficient catalysts.