Photocatalytic syngas synthesis from CO_(2) and H_(2)O using ultrafine CeO_(2)-decorated layered double hydroxide nanosheets under visible-light up to 600 nm

摘要

The rational design of photocatalyst that can effectively reduce CO_(2) under visible light(l>400 nm),and simultaneously precise control of the products syngas(CO/H2)ratio is highly desirable for the Fischer-Tropsch reaction.In this work,we synthesized a series of CeO_(2)-decorated layered double hydroxides(LDHs,Ce-x)samples for photocatalytic CO_(2) reduction.It was found that the selectivity and productivity of CO and H_(2) from photoreduction of CO_(2) in conjunction with Ru-complex as photosensitizer performed an obvious“volcano-like”trend,with the highest point at Ce-0.15 and the CO/H_(2) ratio can be widely tunable from 1/7.7 to 1/1.3.Furthermore,compared with LDH,Ce-0.15 also drove photocatalytic CO_(2) to syngas under 600 nm irradiation.It implied that an optimum amount of CeO_(2) modifying LDH promoted the photoreduction of CO_(2) to syngas.This report gives the way to fully utilize the rare earth elements and provides a promising route to enhance the photo-response ability and charge injection efficiency of LDH-based photocatalysts in the synthesis of syngas with a tunable ratio under visible light irradiation.