Perovskite quantum dots(PQDs) hold immense potential as photocatalysts for CO_(2) reduction due to their remarkable quantum properties,which facilitates the generation of multiple excitons,providing the necessary high...Perovskite quantum dots(PQDs) hold immense potential as photocatalysts for CO_(2) reduction due to their remarkable quantum properties,which facilitates the generation of multiple excitons,providing the necessary high-energy electrons for CO_(2) photoreduction.However,harnessing multi-excitons in PQDs for superior photocatalysis remains challenging,as achieving the concurrent dissociation of excitons and interparticle energy transfer proves elusive.This study introduces a ligand density-controlled strategy to enhance both exciton dissociation and interparticle energy transfer in CsPbBr_(3) PQDs.Optimized CsPbBr_(3) PQDs with the regulated ligand density exhibit efficient photocatalytic conversion of CO_(2) to CO,achieving a 2.26-fold improvement over unoptimized counterparts while maintaining chemical integrity.Multiple analytical techniques,including Kelvin probe force microscopy,temperaturedependent photoluminescence,femtosecond transient absorption spectroscopy,and density functional theory calculations,collectively affirm that the proper ligand termination promotes the charge separation and the interparticle transfer through ligand-mediated interfacial electron coupling and electronic interactions.This work reveals ligand density-dependent variations in the gas-solid photocatalytic CO_(2) reduction performance of CsPbBr_(3) PQDs,underscoring the importance of ligand engineering for enhancing quantum dot photocatalysis.展开更多
基金supported by the National Natural Science Foundation of China (22225606, 22261142663, and 22176029)the Sichuan Science and Technology Program (2022JDRC0084 and 2021JDJQ0006)the CMA Key Open Laboratory of Transforming Climate Resources to Economy (2023005K)。
文摘Perovskite quantum dots(PQDs) hold immense potential as photocatalysts for CO_(2) reduction due to their remarkable quantum properties,which facilitates the generation of multiple excitons,providing the necessary high-energy electrons for CO_(2) photoreduction.However,harnessing multi-excitons in PQDs for superior photocatalysis remains challenging,as achieving the concurrent dissociation of excitons and interparticle energy transfer proves elusive.This study introduces a ligand density-controlled strategy to enhance both exciton dissociation and interparticle energy transfer in CsPbBr_(3) PQDs.Optimized CsPbBr_(3) PQDs with the regulated ligand density exhibit efficient photocatalytic conversion of CO_(2) to CO,achieving a 2.26-fold improvement over unoptimized counterparts while maintaining chemical integrity.Multiple analytical techniques,including Kelvin probe force microscopy,temperaturedependent photoluminescence,femtosecond transient absorption spectroscopy,and density functional theory calculations,collectively affirm that the proper ligand termination promotes the charge separation and the interparticle transfer through ligand-mediated interfacial electron coupling and electronic interactions.This work reveals ligand density-dependent variations in the gas-solid photocatalytic CO_(2) reduction performance of CsPbBr_(3) PQDs,underscoring the importance of ligand engineering for enhancing quantum dot photocatalysis.
