Transmission FT-IR and Knudsen Cell Study of the Heterogeneous Reactivity of Gaseous Nitrogen Dioxide on Mineral Oxide Particles
Transmission FT-IR and Knudsen Cell Study of the Heterogeneous Reactivity of Gaseous Nitrogen Dioxide on Mineral Oxide Particles
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DOI：
10.1021/jp991586i
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发表时间：
1999-07
影响因子：
2.9
通讯作者：
G. M. Underwood;T. Miller;V. Grassian
中科院分区：
文献类型：
--
作者：
G. M. Underwood;T. Miller;V. Grassian
研究了气态二氧化氮在矿物氧化物颗粒上的非均相反应性。特别是，我们进行了光谱和动力学测量，以研究 298 K 下 NO2 在 Al2O3、Fe2O3 和 TiO2 上的表面反应。气相产物和表面结合产物都是由 NO2 与这些矿物氧化物颗粒的反应形成的。在低覆盖率下，暴露于气态 NO2 的矿物氧化物表面的 FT-IR 光谱显示出由于表面亚硝酸盐（特别是螯合亚硝基物质）引起的吸收。随着覆盖率的增加，表面充满了以几种不同的键合配位（单齿、双齿和桥接）键合的表面硝酸盐。主要气相产物是 NO，但也有少量 (<1%) 可检测到的 N2O。使用与四极质谱仪耦合的克努森池反应器来测量这些氧化物颗粒上 NO2 的吸收系数 γ 并表征气相产物的形成。努森细胞数据显示NO...
The heterogeneous reactivity of gaseous nitrogen dioxide on mineral oxide particles was investigated. In particular, spectroscopic and kinetic measurements have been made to investigate surface reactions of NO2 on Al2O3, Fe2O3, and TiO2 at 298 K. Both gas-phase and surface-bound products are formed from the reaction of NO2 with these mineral oxide particles. At low coverages, FT-IR spectra of the mineral oxide surface exposed to gaseous NO2 show absorptions due to surface nitrite, specifically a chelating nitrito species. As the coverage increases, the surface becomes populated with surface nitrate bonded in several different bonding coordinations (monodentate, bidentate, and bridging). The predominant gas-phase product is NO, although there is a small amount (<1%) of detectable N2O. A Knudsen cell reactor coupled to a quadrupole mass spectrometer was used to measure the uptake coefficient, γ, for NO2 on these oxide particles and to characterize gas-phase product formation. The Knudsen cell data showed NO...