A new iodoplumbate/organic hybrid,[(Et_2DABCO)_2(Pb_3I_(11))(H3 O)]n(1,Et_2DABCO = N,N?-diethyl-1,4-diazabicyclo[2.2.2] octane) has been synthesized using solution method.According to X-ray diffraction stru...A new iodoplumbate/organic hybrid,[(Et_2DABCO)_2(Pb_3I_(11))(H3 O)]n(1,Et_2DABCO = N,N?-diethyl-1,4-diazabicyclo[2.2.2] octane) has been synthesized using solution method.According to X-ray diffraction structural analysis,the unique(Pb_3I_(11))_n^(5n-) chain in 1 is constructed from face-and edge-sharing PbI_6 octahedra,which is templated by(Et_2DABCO)^(2+) dication possessing both rigidity and flexibility.C-H...I hydrogen bonds contribute to the structure extending from 1D chains to a 3D network.Its energy band gap of 2.64 eV indicates its broad-gap semiconductor nature.It exhibits both photocurrent response property and photocatalytic activity for the degradation of rhodamine B.展开更多
The photocatalytic kinetics of BPA (4, 4'-isopropylidenediphenol), a representative endocrine disruptor, was explored using immobilized ZnO nanoparticles as a photocatalyst in a laboratory scale photocatalytic reac...The photocatalytic kinetics of BPA (4, 4'-isopropylidenediphenol), a representative endocrine disruptor, was explored using immobilized ZnO nanoparticles as a photocatalyst in a laboratory scale photocatalytic reactor. The conditions of photocatalytic degradation were optimized. Direct photocatalytic degradation of BPA was undertaken in an aqueous solution containing ZnO nanoparticles under the optimized experimental conditions. The effects of various factors, such as initial BPA concentrations, initial pH values and various anions (CI, NO3, COa2, SO42-, HCO3") were investigated. In the case of the nanoparticles derived films, the photocatalytic efficiency was found not to be remarkably related with the calcination temperature employed in the coating process. Screen-printed ZnO nanoparticles films obtained in the optimal processing conditions showed that the photocatalytic activity is comparable to ZnO nanoparticles in aqueous suspensions. Over 90% degradation efficiency of BPA was achieved under the optimum conditions. The degradation rates in all photocatalytic experiments were linear with the degradation efficiencies of BPA by regression analysis (r ≥ 0.99). The results showed that the degradation kinetics of BPA in the reactor with immobilized nano-ZnO film as photocatalyst was in agreement with a pseudo-first order rate law.展开更多
Anatase TiO2 with a variant percentage of exposed (001) facets was prepared under hydrothermal processes by adjusting the volume of HF, and the photocatalytic mechanism was studied from atomic-molecular scale by HRT...Anatase TiO2 with a variant percentage of exposed (001) facets was prepared under hydrothermal processes by adjusting the volume of HF, and the photocatalytic mechanism was studied from atomic-molecular scale by HRTEM and Raman spectroscopy. It was revealed that: 1) From HRTEM observations, the surface of original TiO2 with exposed (001) facets was clean without impurity, and the crystal lattice was clear and completed; however, when mixed with methylene blue (MB) solution, there were many 1 nm molecular absorbed at the surface of TiO2; after the photocatalytic experiment, MB molecules disappeared and the TiO2 lattice image became fuzzy. 2) The broken path of the MB chemical bond was obtained by Raman spectroscopy, i.e., after the irradiation of the light, the vibrational mode of C-N-C disappeared due to the chemical bond breakage, and the groups containing C-N bond and carbon rings were gradually decomposed. Accordingly, we propose that the driving force for breaking the chemical bond and the disappearance of groups is from the surface lattice distortion of TiO2 during photocatalyzation.展开更多
基金supported by the National Natural Science Foundation of China(No.51778374)the Shenzhen Science and Technology Funding Project(JCYJ20150630114140635)
文摘A new iodoplumbate/organic hybrid,[(Et_2DABCO)_2(Pb_3I_(11))(H3 O)]n(1,Et_2DABCO = N,N?-diethyl-1,4-diazabicyclo[2.2.2] octane) has been synthesized using solution method.According to X-ray diffraction structural analysis,the unique(Pb_3I_(11))_n^(5n-) chain in 1 is constructed from face-and edge-sharing PbI_6 octahedra,which is templated by(Et_2DABCO)^(2+) dication possessing both rigidity and flexibility.C-H...I hydrogen bonds contribute to the structure extending from 1D chains to a 3D network.Its energy band gap of 2.64 eV indicates its broad-gap semiconductor nature.It exhibits both photocurrent response property and photocatalytic activity for the degradation of rhodamine B.
文摘The photocatalytic kinetics of BPA (4, 4'-isopropylidenediphenol), a representative endocrine disruptor, was explored using immobilized ZnO nanoparticles as a photocatalyst in a laboratory scale photocatalytic reactor. The conditions of photocatalytic degradation were optimized. Direct photocatalytic degradation of BPA was undertaken in an aqueous solution containing ZnO nanoparticles under the optimized experimental conditions. The effects of various factors, such as initial BPA concentrations, initial pH values and various anions (CI, NO3, COa2, SO42-, HCO3") were investigated. In the case of the nanoparticles derived films, the photocatalytic efficiency was found not to be remarkably related with the calcination temperature employed in the coating process. Screen-printed ZnO nanoparticles films obtained in the optimal processing conditions showed that the photocatalytic activity is comparable to ZnO nanoparticles in aqueous suspensions. Over 90% degradation efficiency of BPA was achieved under the optimum conditions. The degradation rates in all photocatalytic experiments were linear with the degradation efficiencies of BPA by regression analysis (r ≥ 0.99). The results showed that the degradation kinetics of BPA in the reactor with immobilized nano-ZnO film as photocatalyst was in agreement with a pseudo-first order rate law.
文摘Anatase TiO2 with a variant percentage of exposed (001) facets was prepared under hydrothermal processes by adjusting the volume of HF, and the photocatalytic mechanism was studied from atomic-molecular scale by HRTEM and Raman spectroscopy. It was revealed that: 1) From HRTEM observations, the surface of original TiO2 with exposed (001) facets was clean without impurity, and the crystal lattice was clear and completed; however, when mixed with methylene blue (MB) solution, there were many 1 nm molecular absorbed at the surface of TiO2; after the photocatalytic experiment, MB molecules disappeared and the TiO2 lattice image became fuzzy. 2) The broken path of the MB chemical bond was obtained by Raman spectroscopy, i.e., after the irradiation of the light, the vibrational mode of C-N-C disappeared due to the chemical bond breakage, and the groups containing C-N bond and carbon rings were gradually decomposed. Accordingly, we propose that the driving force for breaking the chemical bond and the disappearance of groups is from the surface lattice distortion of TiO2 during photocatalyzation.