Revealing Topography Evolution of Glass Surface under Air Pollution by Atomic Force Microscope

Air pollution has become a matter of close concern to people with the continuous development of human society. However, the knowledge of air pollution mechanisms remains insufficient, and there is a lack of evaluation methods for actual pollution. In this paper, air pollution in Internet cafe was studied by detecting surface topography of glass slides after different exposure time by an atomic force microscope (AFM). It is found that the adsorption of air pollutants on glass surface undergoes initial aggregation, particle growth and interparticle deposition, and final full coverage. The chemical composition of contaminated glass surface was further analyzed by an X-ray photoelectron spectrometer, showing that the pollution was mainly composed of hydrocarbons regardless of exposure time. Cleaning experiments show that NaHCO₃ solution can be the most effective one with saponification reaction and hydrolysis to remove the adsorbed contaminations. This study provides an alternative way for investigating air pollution and a reference for cleaning polluted material surfaces.