Matched micro-geometrical configuration leading to hetero-interfacial intimate contact of MoS2 @UiO-66-NH2 Z-scheme heterojunction for efficient photocatalytic CO2 reduction

Z-scheme heterojunction is an effective strategy in photocatalysis, when hetero-interfacial intimate con-tact is the center of high-performance Z-scheme heterojunction structure. Here, x-MoS2 [x = plate (p), flower (f), and solid sphere (s)] with extensive optical absorption and high conductivity and stable UiO-66-NH2(y) (y = 10 0, 30 0, and 50 0 nm) with rich Lewis's acid sites were integrated to a series of x- MoS2@UiO-66-NH2(y) Z-scheme heterojunctions, which were fully characterized and used for photocat-alytic reduction of CO2 (pCO2RR) into CH4 and CO. In response to the difficult modification of MoS2 and loose contact of composite bulk materials, the micro-geometric configurations on the size of UiO-66-NH2 and the morphology of MoS2 were optimized to achieve an intimate contact. The Z-scheme heterojunc-tion f-MoS2 @UiO-66-NH2 (100 nm) with perfectly matched micro-geometric configuration exhibited an excellent electron consumption rate ( Rele ) of 263.78 mu mol g-1 h-1 and a high CH4 yield of 27.18 mu mol g-1 h-1 with a selectivity of 82.44%, being far superior to most MoS2- and MOFs-based heterojunctions. Com-prehensive investigations with extensive photoelectric characterizations, control experiments, and den-sity functional theory (DFT) calculations demonstrate that the excellent photocatalytic performance of f-MoS2 @UiO-66-NH2 (100 nm) could be attributed to that (i) the low size of UiO-66-NH2 strengthens mutual alignment and increases outer surface to maximize heterointerface contact with MoS2, acceler-ating the interfacial charge transfer; (ii) the hierarchical structure of f-MoS2 with optimal basal plane curvature greatly reduces contact barriers to present a high charge throughput with a charge excita-tion rate of 1.967 mV, smooth initiating the 8-electron CO2 methanation. Additionally, the durability of f-MoS2 @UiO-66-NH2 (100 nm) was also investigated.(c) 2023 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.