The team of academician Xie Yi and Professor Zhang Qun made new progress in the study of two-dimensional ultra-thin black phosphorus photocatalysis

Recently, Professor Xie Yi and Professor Zhang Qun from the school of chemistry and materials science, University of science and technology of China have made new progress in the study of the photoactivation process of two-dimensional ultra-thin black phosphorus The researchers confirmed the subband structure in the two-dimensional ultra-thin black phosphorus, and realized the photocatalytic process with the characteristics of optical switch in the typical inorganic semiconductor materials for the first time The research results were published in J am Chem SOC., 10.1021/jacs.8b00719 under the title of "optically switched photocatalysis in ultrathin black phosphorus nanosheets" In recent years, due to the unique crystal structure and electronic structure, low-dimensional semiconductor materials show a fascinating prospect in the field of photocatalysis However, the enhanced multi-body effect in low dimensional semiconductors makes the materials present different energy band structures and photoexcitation processes than their bulk materials, and then has an impact on their photocatalytic processes Therefore, it is of great significance to explore and understand the influence mechanism of multi-body effect on the photocatalytic process of low dimensional semiconductor materials Therefore, the researchers focus on a new two-dimensional material, black phosphorus Nanoflake Aiming at the strong multi-body effect and quasi one-dimensional energy band distribution of the material, the possible sub-band structure and photon energy dependent optical excitation process in the system are proposed The source of structure characterization of ultra-thin black phosphorus nano tablets: J am Chem SOC Researchers prepared ultra-thin black phosphorus nano tablets by liquid phase stripping method, and studied their photoexcitation process Combined with the photoluminescence and ultrafast spectra, the researchers confirmed that under the excitation of visible light and ultraviolet light, the black phosphorus nano sheet showed two sets of significantly different fluorescence emission and dynamic relaxation processes, respectively The results revealed that the sub band structure in the two-dimensional ultra-thin black phosphorus and the photoexcitation process dependent on the excitation photon energy Because of this, the generation of the active oxygen species in the photocatalysis of the black phosphorus nano tablet has remarkable optical switching characteristics: under the excitation of visible light and ultraviolet light, the main active oxygen species produced by the black phosphorus nano tablet are singlet oxygen and hydroxyl radical, respectively This work provides a new way to optimize the photocatalytic properties of materials by means of photoexcitation control strategy Paper link: https://pubs.acs.org/doi/10.1021/jacs.8b00719 corresponding author: academician Xie Yi Home Page: http://scms.ustc.edu.cn/2010/0925/c239a28555/page.htm introduction of academician Xie Yi Professor Zhang Qun: http://dcp.ustc.edu.cn/2013/1209/c44442a39711/page.htm Professor Zhang Qun