Construction of Z-scheme W18O49/NiAl-LDH heterojunction with photothermal effect for photocatalytic reduction of CO2

Abstract

Recently, the photocatalytic CO2 reduction technology is an effective solution to remit the energy crisis. In order to improve the photocatalytic performance, Z-scheme W18O49/NiAl-LDH composite catalysts were prepared by hydrothermal method. Fortunately, the prepared catalysts revealed excellent photocatalytic performance under the simulated sunlight, and CO and CH4 could be detected in the reduction products. WO/LDH-0.5 catalyst possessed the optimal activity, with CO and CH4 yield of 37.09 and 8.01 µmol g-1h−1 separately, which were 7.9 and 3.6 times that of NiAl-LDH monomer. In addition, W18O49 endowed W18O49/NiAl-LDH catalysts with photothermal effect, which raised the surface temperature and facilitated the catalytic reaction. Meanwhile, the Z-scheme heterojunction composed of flower-like NiAl-LDH and urchin-like W18O49 accelerated the separation of photoexcited carriers and enhanced the redox ability. Through a series of characterizations and investigations, this work is promising to break new ground for the design of photocatalysts with photothermal effect.