Photothermal-driven CO2 reduction over Nd2O3/TiO2 heterojunction catalysts in aqueous medium

Abstract

Elevated carbon dioxide levels, a major environmental concern, pose challenges for causing many climate problems. Addressing this, conversion CO2 into valuable chemicals is highly important. In this work, we explore photothermal catalytic CO2 reduction, an attractive approach that combines photocatalysis and thermal catalysis. We developed an enhanced Nd2O3/TiO2 catalyst using the sol-gel method, which significantly improves the efficiency of converting CO2 to CO in the presence of water. This catalyst exhibited a CO production rate of 22 μmol·gcat−1·h−1 at 130 °C, markedly surpassing the performance of sole photocatalysis by 7.3 times. Through systematic characterizations, we discovered that Nd2O3 prevents TiO2’s transition from anatase to rutile, thereby increasing CO2 adsorption and creating more vacancies. The interface between Nd2O3 and TiO2 forms a Z-scheme heterojunction, crucial for the simultaneous reduction of CO2 and oxidation of water. This research introduces a promising catalyst for photothermal CO2 reduction, which also acts as a reducing reagent. The strategic engineering of dual metal oxide interfaces in this catalyst suggests its applicability in a range of photothermal catalytic processes, marking a significant advancement in the field of CO2 utilization.