Hydrovoltaic effect-enhanced photocatalysis by polyacrylic acid/cobaltous oxide-nitrogen doped carbon system for efficient photocatalytic water splitting.

Xin, Xu; Zhang, Youzi; Wang, Ruiling; Wang, Yijin; Guo, Peng; Li, Xuanhua · Nat Commun · 2023

basic_science · Level V

Where this comes from

Abstract

Severe carrier recombination and the slow kinetics of water splitting for photocatalysts hamper their efficient application. Herein, we propose a hydrovoltaic effect-enhanced photocatalytic system in which polyacrylic acid (PAA) and cobaltous oxide (CoO)-nitrogen doped carbon (NC) achieve an enhanced hydrovoltaic effect and CoO-NC acts as a photocatalyst to generate H<sub>2</sub> and H<sub>2</sub>O<sub>2</sub> products simultaneously. In this system, called PAA/CoO-NC, the Schottky barrier height between CoO and the NC interface decreases by 33% due to the hydrovoltaic effect. Moreover, the hydrovoltaic effect induced by H<sup>+</sup> carrier diffusion in the system generates a strong interaction between H<sup>+</sup> ions and the reaction centers of PAA/CoO-NC, improving the kinetics of water splitting in electron transport and species reaction. PAA/CoO-NC exhibits excellent photocatalytic performance, with H<sub>2</sub> and H<sub>2</sub>O<sub>2</sub> production rates of 48.4 and 20.4 mmol g<sup>-1</sup> h<sup>-1</sup>, respectively, paving a new way for efficient photocatalyst system construction.