Hierarchical SnO2 nanoflowers assembled by atomic thickness nanosheets were prepared by facile one-pot solvothermal method with acetone/water mixture as solvent. The crystal structure, morphology and the microstructur...Hierarchical SnO2 nanoflowers assembled by atomic thickness nanosheets were prepared by facile one-pot solvothermal method with acetone/water mixture as solvent. The crystal structure, morphology and the microstructure of the as-prepared products were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and atomic force microscope （AFM）. Results revealed that the nanoflowers （2-4 μm） were assembled by the ultrathin SnO2 nanosheets （3.1 nm esti- mated by AFM）. When tested as anode material for lithium ion batteries, the SnO2 nanoflowers showed improved cy- cling stability comparing with the commercial SnO2 parti- cles. The reversible charge capacity of SnO2 nanoflowers maintained 350.7 mAh/g after 30 cycles, while that of the commercial SnO2 was only 112.2 mAh/g. The high re- versible capacity and good cycling stability could be ascri- bed to the hierarchical nanostructure, atomic thickness nanosheets and large surface area of the SnO2 nanoflowers.展开更多
It is highly desired to improve the photoelectric property of nanosized BiOBr by promoting the photogenerated charge transfer and separation. Herein, SnO2 and Ag comodified BiOBr nanocomposites(Ag-SO-BOB) have been pr...It is highly desired to improve the photoelectric property of nanosized BiOBr by promoting the photogenerated charge transfer and separation. Herein, SnO2 and Ag comodified BiOBr nanocomposites(Ag-SO-BOB) have been prepared through a simple one-pot hydrothermal method.Surface photovoltage response of BiOBr nanoplates has 4.1-time enhancement after being modified with SnO2 nanoparticles. Transient-state surface photovoltage(TS-SPV) and the atmosphere-controlled steady-state surface photovoltage spectroscopy(AC-SPS) confirmed that this exceptional enhancement of the photovoltage response can be ascribed to the coupled SnO2 acting as platform for accepting the photoelectrons from BiOBr so as to prolong the lifetime and enhance charge separation. Remarkably, the surface photovoltage response can be further enhanced by synchronously introducing Ag nanoparticles, which is up to 15.4-times enhancement compared with bulk BiOBr nanoplates. The enhancement can be attributed to the improved O2 adsorption by introducing Ag to further enhance charge separation. Finally, the synergistic effect of SnO2 and Ag co-modification enhances the surface photovoltage response due to the enhanced charge separation and promoted O2 adsorption, which is also confirmed through photoelectrochemistry and photocatalytic experiment.展开更多
基金supported by the National Natural Science Foundation of China(21475085,21271125 and B010601)the Innovation Scientists and Technicians Troop Construction Projects of Henan Province,Program for Innovative Research Team in Science and Technology in University of Henan Province(2012TRTSTHN018)
文摘Hierarchical SnO2 nanoflowers assembled by atomic thickness nanosheets were prepared by facile one-pot solvothermal method with acetone/water mixture as solvent. The crystal structure, morphology and the microstructure of the as-prepared products were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and atomic force microscope （AFM）. Results revealed that the nanoflowers （2-4 μm） were assembled by the ultrathin SnO2 nanosheets （3.1 nm esti- mated by AFM）. When tested as anode material for lithium ion batteries, the SnO2 nanoflowers showed improved cy- cling stability comparing with the commercial SnO2 parti- cles. The reversible charge capacity of SnO2 nanoflowers maintained 350.7 mAh/g after 30 cycles, while that of the commercial SnO2 was only 112.2 mAh/g. The high re- versible capacity and good cycling stability could be ascri- bed to the hierarchical nanostructure, atomic thickness nanosheets and large surface area of the SnO2 nanoflowers.
基金financial support from the National Natural Science Foundation of China (U1401245, 21501052 and 91622119)the Program for Innovative Research Team in Chinese Universities (IRT1237)+2 种基金China Postdoctoral Science Foundation (2015M570304)the Special Funding for Postdoctoral of Heilongjiang Province (LBH-TZ06019)UNPYSCT-2016173
文摘It is highly desired to improve the photoelectric property of nanosized BiOBr by promoting the photogenerated charge transfer and separation. Herein, SnO2 and Ag comodified BiOBr nanocomposites(Ag-SO-BOB) have been prepared through a simple one-pot hydrothermal method.Surface photovoltage response of BiOBr nanoplates has 4.1-time enhancement after being modified with SnO2 nanoparticles. Transient-state surface photovoltage(TS-SPV) and the atmosphere-controlled steady-state surface photovoltage spectroscopy(AC-SPS) confirmed that this exceptional enhancement of the photovoltage response can be ascribed to the coupled SnO2 acting as platform for accepting the photoelectrons from BiOBr so as to prolong the lifetime and enhance charge separation. Remarkably, the surface photovoltage response can be further enhanced by synchronously introducing Ag nanoparticles, which is up to 15.4-times enhancement compared with bulk BiOBr nanoplates. The enhancement can be attributed to the improved O2 adsorption by introducing Ag to further enhance charge separation. Finally, the synergistic effect of SnO2 and Ag co-modification enhances the surface photovoltage response due to the enhanced charge separation and promoted O2 adsorption, which is also confirmed through photoelectrochemistry and photocatalytic experiment.
