Polyaniline/Carbon Dots Composite as a Highly Efficient Metal-Free Dual-Functional Photoassisted Electrocatalyst for Overall Water Splitting
Xiaoqing Gu, Zhaomin Chen, Yi Li, Jie Wu, Xiao Wang, Hui Huang, Yang Liu, Bin Dong, Mingwang Shao, Zhenhui Kang
Abstract
Photoassisted electrocatalytic (P-EC) water splitting for H2 production has received much attention. Here, we report a metal-free bifunctional photoassisted catalyst of a polyaniline/carbon dots (PANI/CDs) composite for overall water splitting. In a neutral electrolyte, under visible light, the overpotentials of the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) for PANI/CDs/NF are reduced by 150 and 65 mV to reach the current densities of 30 and 20 mA cm–2, respectively. In a full water-splitting cell, under visible light, the current density is 13.27 mA cm–2 at 2.0 V, which increases by 62.8% compared with that under the dark conditions (8.15 mA cm–2). The in situ transient photovoltage (TPV) tests were used to study the light-induced effects on half-reactions of water splitting, as well as the charge-transfer kinetic characteristics at the catalyst interface.