This letter reports a study on producing gas-phase O 2(a 1Δ) by decomposition of triphenyl phosphite ozonide ((C 6H 5O) 3PO 3, TPPO 3) under a number of reaction conditions. For the first time, the cooperative emissi...This letter reports a study on producing gas-phase O 2(a 1Δ) by decomposition of triphenyl phosphite ozonide ((C 6H 5O) 3PO 3, TPPO 3) under a number of reaction conditions. For the first time, the cooperative emission at wavelengths 634 and 703 nm of O 2(a 1Δ) generated by TPPO 3 decomposition are observed. Specifically, under the condition of catalyzed decomposition by pyridine of TPPO 3 solution in CFCl 3 at low temperature, the emission spectrum is the same as that from the basic hydrogen peroxide plus chlorine reaction. This shows the feasibility of developing a new source for singlet delta oxygen. However, in the experiments of spontaneous decomposition of solid TPPO 3 and thermal decomposition of TPPO 3 solution on a high temperature surface, the spectra have a wide emission background around the 634 and 703 nm peaks, which indicates the production of some excited species than O 2(a 1△). Besides, there are about 2%～3%CO and 1.5%～2%CO 2 in the gaseous products together with a small amount of insoluble in acetone solid product, which imply that other than the formation of O 2(a 1△) and TPPO by unimolecular decomposition of TPPO 3, more complicated reactions may take place. The study of the reaction mechanism, the optimization of the expertise of O 2(a 1△) generation by TPPO 3 decomposition as well as measurement of absolute concentration of O 2(a 1△) are under way.展开更多
A flow system was set up to measure the quenching probability ~ of O2（1△g） on various O2- adsorbed metal surfaces including Cu, Cr, Ni, and Ag. increased with both the duration of the experiment and the O2（1△g）...A flow system was set up to measure the quenching probability ~ of O2（1△g） on various O2- adsorbed metal surfaces including Cu, Cr, Ni, and Ag. increased with both the duration of the experiment and the O2（1△g） concentration. After several hours evacuation to a few Pa, γ can return to its original value. A deactivation mechanism of O2（1△g） is suggested by considering first the weak chemisorption of O2（1△g） on the surface adsorption sites, followed by the near resonant energy transfer between the gas phase O2（1△g） and surface O2（1△g）. A phenomenological model in accord with the experimental fact has been proposed together with relevant kinetic equations.展开更多
文摘This letter reports a study on producing gas-phase O 2(a 1Δ) by decomposition of triphenyl phosphite ozonide ((C 6H 5O) 3PO 3, TPPO 3) under a number of reaction conditions. For the first time, the cooperative emission at wavelengths 634 and 703 nm of O 2(a 1Δ) generated by TPPO 3 decomposition are observed. Specifically, under the condition of catalyzed decomposition by pyridine of TPPO 3 solution in CFCl 3 at low temperature, the emission spectrum is the same as that from the basic hydrogen peroxide plus chlorine reaction. This shows the feasibility of developing a new source for singlet delta oxygen. However, in the experiments of spontaneous decomposition of solid TPPO 3 and thermal decomposition of TPPO 3 solution on a high temperature surface, the spectra have a wide emission background around the 634 and 703 nm peaks, which indicates the production of some excited species than O 2(a 1△). Besides, there are about 2%～3%CO and 1.5%～2%CO 2 in the gaseous products together with a small amount of insoluble in acetone solid product, which imply that other than the formation of O 2(a 1△) and TPPO by unimolecular decomposition of TPPO 3, more complicated reactions may take place. The study of the reaction mechanism, the optimization of the expertise of O 2(a 1△) generation by TPPO 3 decomposition as well as measurement of absolute concentration of O 2(a 1△) are under way.
基金This work was supported by the National Natural Science Foundation of China （No.20703045） and the National Key Basic Research and Science Foundation （No.2007CBS15202）.
文摘A flow system was set up to measure the quenching probability ~ of O2（1△g） on various O2- adsorbed metal surfaces including Cu, Cr, Ni, and Ag. increased with both the duration of the experiment and the O2（1△g） concentration. After several hours evacuation to a few Pa, γ can return to its original value. A deactivation mechanism of O2（1△g） is suggested by considering first the weak chemisorption of O2（1△g） on the surface adsorption sites, followed by the near resonant energy transfer between the gas phase O2（1△g） and surface O2（1△g）. A phenomenological model in accord with the experimental fact has been proposed together with relevant kinetic equations.
