Electronically tuned defective Prussian-blue on graphene for electrochemical water splitting

Exploiting high-performance and stable bifunctional electrocatalysts is highly desirable for water splitting applications to obtain large-scale renewable and clean fuels. Herein, a defective Prussian-blue (delta-PB or Fe-1.23(III)[Fe-1.12(II)(CN)(6)](0.87).delta(0.13)) on graphene composite electrocatalyst was fabricated through a facile hydrolytic precipitation process, followed by a single-step carbonization treatment at 600 degrees C (denoted as 8-PB/G-600). The resultant optimized delta-PB/G-600 exhibits remarkable electrocatalytic water splitting in alkaline media, producing lower overpotentials of 189 and 105 mV at a current density of 10 mA cm(-2) for the oxygen evolution reaction and hydrogen evolution reaction, respectively. Most importantly, the 8-PB/G-600 shows remarkable durability for both reactions. The remark-able electrocatalysis was attributed to the abundant active sites and high electrical conductivity with a defective nature, which not only facilitate the electrolyte flux but also maintain the structural stability of 8-PB/G-600. Additionally, the high surface area confirms the facile mass transport and prompts the gaseous release of the composite. (C) 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Automated summary

In this study, a defective Prussian-blue/graphene composite electrocatalyst was prepared and exhibited remarkable electrocatalytic water splitting performance and durability in alkaline media.