Unassisted selective solar hydrogen peroxide production by an oxidised buckypaper-integrated perovskite photocathode

Hydrogen peroxide (H(2)O(2)) is an eco-friendly oxidant and a promising energy source possessing comparable energy density to that of compressed H(2). The current H(2)O(2) production strategies mostly depend on the anthraquinone oxidation process, which requires significant energy and numerous organic chemicals. Photocatalyst-based solar H(2)O(2) production comprises single-step O(2) reduction to H(2)O(2), which is a simple and eco-friendly method. However, the solar-to-H(2)O(2) conversion efficiency is limited by the low performance of the inorganic semiconductor-based photoelectrodes and low selectivity and stability of the H(2)O(2) production electrocatalyst. Herein, we demonstrate unassisted solar H(2)O(2) production using an oxidised buckypaper as the H(2)O(2) electrocatalyst combined with a high-performance inorganic-organic hybrid (perovskite) photocathode, without the need for additional bias or sacrificial agents. This integrated photoelectrode system shows 100% selectivity toward H(2)O(2) and a solar-to-chemical conversion efficiency of ~1.463%.