The chemistry of acetaldehyde (CH3CHO) adsorbed on the anatase TiO2(001)-(1×4) surface has been investigated by temperature-programmed desorption (TPD) method. Our experimental results provide the direct evidence...The chemistry of acetaldehyde (CH3CHO) adsorbed on the anatase TiO2(001)-(1×4) surface has been investigated by temperature-programmed desorption (TPD) method. Our experimental results provide the direct evidence that the perfect lattice sites on the anatase TiO2(001)-(1×4) surface are quite inert for the reaction of CH3CHO, but the reduced defect sites on the surface are active for the thermally driven reductive carbon-carbon coupling reactions of CH3CHO to produce 2-butanone and butene. We propose that the coupling reactions of CH3CHO on the anatase TiO2(001)-(1×4) surface should undergo through the adsorption of paired CH3CHO molecules at the reduced defect sites, since the existing reduced Ti pairs provide the suitable adsorption sites.展开更多
Optimizing the interfacial properties between perovskite and carbon electrodes has always been an important way to improve the photoelectric conversion efficiency(PCE)of carbon-based perovskite solar cells(C-PSCs)and ...Optimizing the interfacial properties between perovskite and carbon electrodes has always been an important way to improve the photoelectric conversion efficiency(PCE)of carbon-based perovskite solar cells(C-PSCs)and facilitate their commercialization.In this paper,nitrogen-doped graphene quantum dots(N-GQDs)with fluorescent properties were successfully prepared using inexpensive coal as raw material by a facile and environmentally friendly chemical reagent oxidation.The results show that the electron-rich pyridinic nitrogen in N-GQDs can act as Lewis bases to form coordination bonds with uncoordinated lead ions by sharing electron pairs,thereby reducing the defect density and nonradiative recombination of photo-generated electron-hole,and extending lifetime of charge carriers.In addition,due to the passivation of N-GQDs,the hysteresis effect of the device is significantly reduced and the long-term stability is also improved.By optimizing the concentration,the PCE of C-PSCs achieved a maximum of 14.31%,which was improved by 20.25%compared with 11.90%of the pristine C-PSCs.This work provides a facile,environmentally friendly and efficient strategy for improving the overall performance of C-PSCs using inexpensive coal-based N-GQDs.展开更多
基金supported by the Ministry of Science and Technology of China (No.2016YFA0200603)the National Natural Science Foundation of China (No.91421313 and No.21573207)Anhui Initiative in Quantum Information Technologies (AHY090300)
文摘The chemistry of acetaldehyde (CH3CHO) adsorbed on the anatase TiO2(001)-(1×4) surface has been investigated by temperature-programmed desorption (TPD) method. Our experimental results provide the direct evidence that the perfect lattice sites on the anatase TiO2(001)-(1×4) surface are quite inert for the reaction of CH3CHO, but the reduced defect sites on the surface are active for the thermally driven reductive carbon-carbon coupling reactions of CH3CHO to produce 2-butanone and butene. We propose that the coupling reactions of CH3CHO on the anatase TiO2(001)-(1×4) surface should undergo through the adsorption of paired CH3CHO molecules at the reduced defect sites, since the existing reduced Ti pairs provide the suitable adsorption sites.
基金financially supported by the National Natural Science Foundation of China(52162035)the Open project of State Key Laboratory of Fine Chemicals,the Dalian University of Technology(KF2004)the Graduate Research Innovation Project of Xinjiang Uyghur Autonomous Region(XJ2022G045)。
文摘Optimizing the interfacial properties between perovskite and carbon electrodes has always been an important way to improve the photoelectric conversion efficiency(PCE)of carbon-based perovskite solar cells(C-PSCs)and facilitate their commercialization.In this paper,nitrogen-doped graphene quantum dots(N-GQDs)with fluorescent properties were successfully prepared using inexpensive coal as raw material by a facile and environmentally friendly chemical reagent oxidation.The results show that the electron-rich pyridinic nitrogen in N-GQDs can act as Lewis bases to form coordination bonds with uncoordinated lead ions by sharing electron pairs,thereby reducing the defect density and nonradiative recombination of photo-generated electron-hole,and extending lifetime of charge carriers.In addition,due to the passivation of N-GQDs,the hysteresis effect of the device is significantly reduced and the long-term stability is also improved.By optimizing the concentration,the PCE of C-PSCs achieved a maximum of 14.31%,which was improved by 20.25%compared with 11.90%of the pristine C-PSCs.This work provides a facile,environmentally friendly and efficient strategy for improving the overall performance of C-PSCs using inexpensive coal-based N-GQDs.
