Rational design and facile synthesis of efficient environmentally friendly all-inorganic lead-free halide perovskite catalysts are of great significance in photocatalytic CO 2 reduction. Aiming at photogenerated charge carrier separation and CO 2 reaction dynamics, in this paper, a CsCuCl 3 /Cu nanocrystals (NCs) heterojunction catalyst is designed and synthesized via a simple acid-etching solution process by using Cu 2 O as the sacrificed template. Due to the disproportionation reaction of Cu 2 O induced by concentrated hydrochloric acid, Cu NCs can be deposited onto the surface of CsCuCl 3 microcrystals directly and tightly. As revealed by photoelectrochemical analysis, in situ Fourier transform infrared spectra, etc., the Cu NCs contribute a lot to extracting photoelectrons of CsCuCl 3 to improve the charge separation efficiency, regulating the CO 2 adsorption and activation, and also stabilizing the reaction intermediates. Therefore, CsCuCl 3 /Cu heterojunction exhibits a total electron consumption rate of 58.77 µmol g −1 h −1 , which is 2.9-fold of that of single CsCuCl 3 . Moreover, high CH 4 selectivity of up to 92.7% is achieved, which is much higher than that of CsCuCl 3 (50.4%) and most lead-free halide perovskite-based catalysts. This work provides an ingenious but simple strategy to rationally design cocatalysts in situ decorated perovskite catalysts for manipulating both the catalytic activity and the product selectivity.
Yi Lu,Ahmed Mahmoud Idris,Ping Lu,Xinyan Jiang,Jin Wang,Hao Zheng,Xiandan Liang,Sheng Li,Zhengquan Li
Photocatalytic selective oxidation represents a sustainable approach for valuable chemical transformations, yet achieving high yield and selectivity of products remains a significant challenge. In this work, we demonstrate that electronic structure modulation of CsCuCl 3 halide perovskites enables highly selective photocatalytic oxidation of toluene to benzaldehyde (BD). By strategically doping Zn into CsCuCl 3 , we achieved control over the electronic modulation of catalytic sites, leading to a remarkable BD yield of 4.08 mmol g −1 h −1 with 85.4 % selectivity under visible light irradiation. Mechanistic investigations revealed that Zn doping creates an optimal electronic structure, which simultaneously facilitates O 2 activation to form superoxide radicals and promotes selective C–H bond activation of toluene. Density functional theory calculations showed that Zn doping induces charge redistribution at Cu and Cl sites, optimizing surface energetics for both O 2 and toluene adsorption while lowering kinetic barriers for the rate-determining steps. The enhanced charge carrier separation efficiency, confirmed by spectroscopic and electrochemical analyses, further contributes to the superior catalytic performance. This work establishes electronic structure engineering as a powerful strategy for developing high-performance single-component photocatalysts and provides new insights into the selective photocatalytic oxidation reactions.