Atmospheric chemistry of 2-nitrobenzaldehyde:Initiated by photo-excitation,OH-oxidation,and small TiO_(2) clusters adsorption catalysis  

作　　者：Feng-Yang Bai Xiang-Huan Liu Ting-Ting Meng Zhou Yu Yi-Chen Wang Shuang Ni Zhen Zhao 

机构地区：[1]Institute of Catalysis for Energy and Environment,College of Chemistry and Chemical Engineering,Shenyang Normal University,Shenyang 110034,China

出　　处：《Journal of Environmental Sciences》2024年第5期123-137,共15页环境科学学报（英文版）

基　　金：supported by the National Natural Science Foundation of China(No.22006101);the Natural Science Foundation of Liaoning Province(No.2023-MS-250);the Basic Scientific Research Foundation Project of Liaoning Province(No.LJKQZ20222283);the National Natural Science Foundation of China-Liaoning Joint Fund(No.U1908204);the Doctoral Research Start-up Fund of Shenyang Normal University(No.BS202124,No.BS202016);the Basic Scientific Research Project of Universities in Liaoning Province(No.LQN202007)。

摘　　要：The fate of 2-nitrobenzaldehyde(2-NBA)is of interest in atmospheric chemistry as it is a semi-volatile organic compound with high photosensitivity.This study presents a quantum chemical study of the gas-phase reactions of 2-NBA photo-excitation and OH-oxidation in the absence and presence of small TiO_(2) clusters.To further understand the unknown photolysis mechanism,the photo-reaction pathways of ground singlet state and the lying excited triplet state of 2-NBA were investigated including the initial and subsequent reactions of proton transfer,direct CO,NO_(2),and HCO elimination routes in the presence of O_(2) and NO.Meanwhile,the OH-mediated degradation of 2-NBA proceeded via five H-extraction and six OH-addition channels by indirect mechanism,which follows a succession of reaction steps initiated by the formation of weakly stable intermediate complexes.The H-extraction from the-CHO group was the dominant pathway with a negative activation energy of-1.22 kcal/mol.The calculated rate coefficients at 200–600 K were close to the experimental data in literature within 308-352 K,and the kinetic negative temperature independence was found in both experimental literature and computational results.Interestingly,2-NBA was favored to be captured onto small TiO_(2) clusters via six adsorption configurations formed via various combination of three types of bonds of Ti…O,Ti…C,and O…H between the molecularly adsorbed 2-NBA and TiO_(2) clusters.Comparison indicted that the chemisorptions of aldehyde oxygen have largest energies.The results suggested adsorption conformations have a respectable impact on the catalysis barrier.This study is significant for understanding the atmospheric chemistry of 2-nitrobenzaldehyde.

关 键 词：2-nitrobenzaldehyde OH radical oxidation Rate coefficient Photolysis mechanism Adsorption catalysis 

分 类 号：X51[环境科学与工程—环境工程]