Hollow Sr/Rh-codoped TiO2 photocatalyst for efficient sunlight-driven organic compound degradation

Abstract

Sunlight-driven photocatalysis has emerged as a potential technology to address organic pollutant issues. Here, we report the first Rh-doped hollow-structured TiO₂ photocatalyst, which is highly active in the photocatalytic decomposition of organic pollutants under solar light. We achieved this by introducing Sr²⁺ as a co-doping agent, which stabilized the hollow structure at high temperatures and enabled us to control the oxidation state of Rh. The designed photocatalyst exhibited strong visible light absorption (up to 600 nm), and a very high surface area (up to 140 m² g⁻¹). As a result, the Sr/Rh-doped TiO₂ hollow photocatalysts demonstrated a photocatalytic efficiency (PE) of 0.242%, which was at least 8 times higher than that of commercial TiO₂ (0.03%) and 25 times higher than that of bulk Sr/Rh–TiO₂ (0.01%), in the photocatalytic decomposition of isopropanol under solar light irradiation.