Work

Size regulation of Pt cocatalysts and its effect on the performance of photocatalytic CO2 transformation to CH4

Year: 2024

Type: article

Abstract: Platinum is one of the most efficient cocatalysts for photocatalytic reduction of carbon dioxide (CO 2 ) to methane (CH 4 ), but it still suffers from low CO 2 reduction rate and low selectivity of CH 4 . In this study, Pt/TiO 2 catalysts with adjustable Pt particle size (0.55-1.80 nm) were prepared by atomic layer deposition (ALD) and used for photocatalytic reduction of CO 2 to CH 4 . The CH 4 yield and selectivity of the Pt/TiO 2 catalysts showed a volcanic variation trend with the increase of Pt particle size. The 10Pt/TiO 2 with Pt particle size of 1.35 nm exhibit the highest methane yield (71.9 μmol/(g·h)). Especially, a high electron-based selectivity of 81.69% for CH 4 (product-based selectivity of 90.20%), and 100% for hydrocarbons (CH 4 , C 2 H 6 , and C 3 H 8 ) are achieved, no H 2 formation was detected. The CO-DRIFTS, XPS, CO 2 -TPD, H 2 O-TPD, and H 2 -TPD characterizations suggest that the 10Pt/TiO 2 exhibited optimal CO 2 adsorption/activation capacity, suitable H 2 O activation capacity, and higher hydrogen desorption temperature, making the generation rate of active hydrogen species from H 2 O matches their consumption rate for CO 2 hydrogenation. This study opens an avenue for rationally designing highly efficient and selective photocatalysts for photocatalytic CO 2 reduction.

Source: Journal of Fuel Chemistry and Technology

DOI: 10.1016/s1872-5813(24)60472-x

Authors: Yao CHEN, Chaoqiu CHEN, Wentao HAO, Wenlong WANG, Kun XIONG, Yong QIN