Environment Research Institute, Shandong University, Binhai Road 72, Qingdao 266237, China.
School of Life Science, Shandong University, Binhai Road 72, Qingdao 266237, China.
Environ Sci Process Impacts. 2020 Feb 26;22(2):408-417. doi: 10.1039/c9em00550a.
The effects of NO2 and SO2 on the atmospheric heterogeneous reaction of acetic acid on α-Al2O3 in the presence and absence of simulated irradiation were investigated at ambient conditions by using the diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) technique. The experiment was divided into two parts: the heterogeneous reaction experiment and the pre-adsorption reaction experiment under light and dark conditions. In the heterogeneous reaction experiment, solar radiation stimulates the formation of more acetate and nitrate. At the same time, it can promote the partial conversion of sulfites to sulfates in the heterogeneous reaction of SO2 on α-Al2O3 particles. It can be seen that solar radiation plays a significant role in the heterogeneous reactions of inorganic and organic gases on mineral particles. In the pre-adsorption reaction experiment, the pre-adsorbed nitrate, sulfite or sulfate have conspicuous inhibition influence on the formation of acetate in the presence and absence of simulated irradiation. This indicates that the role of pre-adsorbed species should be given more attention for the heterogeneous reaction of acetic acid on the surface of α-Al2O3 particles. When α-Al2O3 particles were pre-adsorbed by different species, simulated irradiation could facilitate the growth of different amounts of acetate. It was found that the extent to which solar radiation contributes to heterogeneous reactions of different kinds of gases on different mineral particles is different. This further emphasizes the complexities of the heterogeneous conversion processes of atmospheric trace gases on the surface of mineral aerosols, promoting a better understanding of the effects of solar radiation and pre-adsorption on the heterogeneous reaction in the atmosphere.
采用漫反射红外傅里叶变换光谱（DRIFTS）技术，在环境条件下研究了 NO2 和 SO2 对模拟光照和黑暗条件下α-Al2O3 上醋酸的非均相反应的影响。实验分为两部分：在非均相反应实验中，太阳辐射刺激了更多的醋酸盐和硝酸盐的形成。同时，它可以促进 SO2 在α-Al2O3 颗粒上的非均相反应中部分亚硫酸盐向硫酸盐的转化。可以看出，太阳辐射在矿物颗粒上无机和有机气体的非均相反应中起着重要作用。在预吸附反应实验中，预吸附的硝酸盐、亚硫酸盐或硫酸盐在有无模拟光照的情况下对醋酸盐的形成具有明显的抑制作用。这表明在α-Al2O3 颗粒表面上的醋酸非均相反应中，预吸附物种的作用应该得到更多的关注。当α-Al2O3 颗粒被不同的物种预吸附时，模拟光照可以促进不同量的醋酸盐的生长。研究发现，太阳辐射对不同矿物颗粒上不同种类气体的非均相反应的贡献程度不同。这进一步强调了大气痕量气体在矿物气溶胶表面非均相转化过程的复杂性，促进了对太阳辐射和预吸附对大气中非均相反应影响的更好理解。
