Dual-function ZnO/CeO2 photocatalyst for simultaneous methane decomposition and CO2 adsorption at room temperature
Sho Usuki, Masashi Morita, Takuto Takada, Tiangao Jiang, Naoko Taki, Yuma Uesaka, Haru Togawa, Kazuyuki Maeda, Ken‐ichi Katsumata, Shanhu Liu, Baoshun Liu, Kazuya Nakata
Abstract
A dual-function ZnO/CeO 2 photocatalyst effectively decomposes methane and captures CO 2 at room temperature. Synthesized using an oxalate-based co-precipitation method, the composite achieved near-complete methane decomposition and adsorbed the resulting CO 2 , thereby significantly enhancing the efficiency of greenhouse gas reduction. This innovative approach addresses both methane and CO 2 emissions, providing a sustainable pathway for environmental remediation under ambient conditions. • Novel ZnO/CeO 2 achieves near-complete methane decomposition at room temperature. • Enhanced charge separation and CH 4 adsorption boost photocatalytic activity. • Dual function: Methane decomposition and CO 2 capture under ambient conditions. • Simple oxalate-based co-precipitation yields stable and reusable photocatalyst. Climate change mitigation urgently requires innovative approaches to address multiple greenhouse gases simultaneously. This study introduces a novel ZnO/CeO 2 composite photocatalyst that demonstrates high efficiency in methane decomposition under ambient conditions, while also exhibiting CO 2 capture capabilities. Synthesized via an oxalate-based co-precipitation method, the ZnO/CeO 2 composite achieved near-complete methane decomposition (from 100 to 4 ppm) within 180 min of UV irradiation at room temperature and ambient pressure. Notably, the ZnO/CeO 2 composite showed significantly enhanced methane adsorption capacity compared to pure ZnO or CeO 2 , which directly contributed to its superior methane decomposition performance. This increased adsorption ability, combined with efficient charge separation at the ZnO/CeO 2 interface, facilitates the rapid and effective decomposition of methane molecules. Furthermore, the composite exhibited simultaneous CO 2 adsorption capacity. The CO 2 generated from the methane decomposition was largely adsorbed by the ZnO/CeO 2 composite, as evidenced by the low detection of CO 2 in the gas phase during the reaction. This dual functionality of enhanced methane decomposition and subsequent CO 2 capture represents an integrated approach for greenhouse gas reduction. This work not only advances the field of greenhouse gas mitigation but also introduces a new paradigm for designing multifunctional environmental remediation materials.