Perovskite quantum dots (PQDs) require ligands on their surfaces to passivate defects and prevent aggregation. However, the ligands construct the interface relationship between the PQDs, which may seriously hinder the...Perovskite quantum dots (PQDs) require ligands on their surfaces to passivate defects and prevent aggregation. However, the ligands construct the interface relationship between the PQDs, which may seriously hinder the carrier transport. Hence, we propose a molecular engineering strategy of using 3,4-ethylenedioxythiophene (EDOT) to perfectly solve this problem, benefiting from its high conjugation and passivation ability to CsPbBr_(3) PQDs. Furthermore, EDOT on the surface of PQDs can be in-situ polymerized under the photocurrent of the photodetector, thus interconnecting the PQDs which enhanced the performance of the photodetectors up to 178% of its initial performance. We have thoroughly investigated the electropolymerization process of EDOT and its passivation effect on PQDs. The simple lateral photodetector based on EDOT PQDs exhibits a high responsivity of 11.96 A/W, which is 104 times higher than that of oleic acid caped PQDs. Due to the protection of poly(3,4-ethylenedioxythiophene) (PEDOT), the photodetector prepared from EDOT PQDs exhibited very high stability, retaining 94% of its performance after six months in air. This strategy provides a solution for the application of PQDs in high performances and stable optoelectronic devices.展开更多
Single-crystal-like TiO2 mesoporous microspheres have been reported with high photocatalytic activity under ultraviolet light (UV light) because of their high specific surface areas and single-crystal-like channel w...Single-crystal-like TiO2 mesoporous microspheres have been reported with high photocatalytic activity under ultraviolet light (UV light) because of their high specific surface areas and single-crystal-like channel walls. In this work, plasmonic gold nanoparticles (Au NPs) and fl-NaYF4: Yb3+, Er3+ upconversion nanoparticles (UCNPs) were composited with single-crystal-like TiO2 mesoporous microspheres through a series of facile approaches, aiming at broadening response region of solar light from UV to visible and near infrared light and enhancing the photocata- lyric activity further. The structure was rationally designed by modifying the pore size of TiO2 mesoporous micro- spheres so as to anchor plasmonic Au NPs, and covering β-NaYF4: Yb3+, Er3+ with SiO2 in order to embed UCNPs into TiO2 mesoporous microspheres via hydrophilic interaction. This work studied the attribution of Au NPs and UCNPs to photocatalysis and found out that combining Au NPs and certain amount of UCNPs with single-crystal- like TiO2 mesoporous microspheres in a monolithic architecture would bring enhanced broadband photocatalytic activity under simulated solar light. Consequently, the composite photocatalyts containing 150 mg UCNPs showed a significant enhancement in reaction rate, which was 36.02% higher than commercial P25 and 85.09% higher than pure TiO2 mesoporous microspheres under simulated solar light.展开更多
基金This work was supported by the National Natural Science Foundation of China(Nos.21676093,21776092,21978087,21838003,and 91834301)the Shanghai Scientific and Technological Innovation Project(Nos.19JC1410400 and 18JC1410600)+2 种基金Shanghai Rising-Star Program(No.18QA1401500)the Innovation Program of Shanghai Municipal Education Commission,Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutes of High Learning,Shanghai Rising-Star Program(No.18QA1401500)the Fundamental Research Funds for the Central Universities(No.222201718002).
文摘Perovskite quantum dots (PQDs) require ligands on their surfaces to passivate defects and prevent aggregation. However, the ligands construct the interface relationship between the PQDs, which may seriously hinder the carrier transport. Hence, we propose a molecular engineering strategy of using 3,4-ethylenedioxythiophene (EDOT) to perfectly solve this problem, benefiting from its high conjugation and passivation ability to CsPbBr_(3) PQDs. Furthermore, EDOT on the surface of PQDs can be in-situ polymerized under the photocurrent of the photodetector, thus interconnecting the PQDs which enhanced the performance of the photodetectors up to 178% of its initial performance. We have thoroughly investigated the electropolymerization process of EDOT and its passivation effect on PQDs. The simple lateral photodetector based on EDOT PQDs exhibits a high responsivity of 11.96 A/W, which is 104 times higher than that of oleic acid caped PQDs. Due to the protection of poly(3,4-ethylenedioxythiophene) (PEDOT), the photodetector prepared from EDOT PQDs exhibited very high stability, retaining 94% of its performance after six months in air. This strategy provides a solution for the application of PQDs in high performances and stable optoelectronic devices.
基金This work is supported by the National Natural Science Foundation of China (Nos. 21236003, 21322607, 21406072, 21471056, 21676093 and 91534202), Shanghai Educational Development Foundation (No. 14CG29), the Basic Research Program of Shanghai (No. 14JCI406402), China Postdoctoral Science Foundation (Nos. 2014M560307, 2014M561497, 2015T80408), and the Fundamental Research Funds for the Central Universities.
文摘Single-crystal-like TiO2 mesoporous microspheres have been reported with high photocatalytic activity under ultraviolet light (UV light) because of their high specific surface areas and single-crystal-like channel walls. In this work, plasmonic gold nanoparticles (Au NPs) and fl-NaYF4: Yb3+, Er3+ upconversion nanoparticles (UCNPs) were composited with single-crystal-like TiO2 mesoporous microspheres through a series of facile approaches, aiming at broadening response region of solar light from UV to visible and near infrared light and enhancing the photocata- lyric activity further. The structure was rationally designed by modifying the pore size of TiO2 mesoporous micro- spheres so as to anchor plasmonic Au NPs, and covering β-NaYF4: Yb3+, Er3+ with SiO2 in order to embed UCNPs into TiO2 mesoporous microspheres via hydrophilic interaction. This work studied the attribution of Au NPs and UCNPs to photocatalysis and found out that combining Au NPs and certain amount of UCNPs with single-crystal- like TiO2 mesoporous microspheres in a monolithic architecture would bring enhanced broadband photocatalytic activity under simulated solar light. Consequently, the composite photocatalyts containing 150 mg UCNPs showed a significant enhancement in reaction rate, which was 36.02% higher than commercial P25 and 85.09% higher than pure TiO2 mesoporous microspheres under simulated solar light.