The lack of kinetic parameters of VOC photochemical conversion especially in the presence of NO and O₃, and product information, will result in the incomplete understanding for the occurrence of haze. In the present study, the photochemical conversion of toluene, one of most significant hydrocarbons of VOCs, in toluene, toluene/NO, toluene/O₃ and reaction systems was assessed for up to 4 days in a smog chamber at 278 K and 308 K. The results indicated that the addition of NO and O₃ promoted the conversion of toluene. The first-order kinetic rate constants of toluene assessed in the toluene reaction system at 278 K and 308 K were 0.12 and 0.19 day⁻¹, respectively. The second-order kinetic rate constants of toluene assessed in the toluene/NO were 0.1 × 10⁻¹³ cm³ molecule⁻¹ day⁻¹ (at 278 K) and 0.9 × 10⁻¹³ cm³ molecule⁻¹ day⁻¹ (at 308 K), and those in the toluene/O₃ reaction systems were 0.06 × 10⁻¹² cm³ molecule⁻¹ day⁻¹ (at 278 K) and 0.11 × 10⁻¹² cm³ molecule⁻¹ day⁻¹ (at 308 K). The small difference of second-order kinetic rate constants between 278 K and 308 K obtained for the toluene/O₃ system when compared with the toluene/NO system indicated the reduced reaction sensitivity of O₃ to the temperature. Several dozens of large molecule products containing up to O₆ heteroatoms were identified by positive ion atmospheric pressure photoionization (+APPI) coupled with Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS), with double bond equivalents up to 18, and carbon numbers ranging within 12–38, respectively. The findings presented herein may provide a new train of thought for the photochemical reaction process of toluene and its conversion in ambient air.

缺少VOC光化学转化的动力学参数，尤其是在NO和O ₃存在的情况下，以及产品信息的缺乏，将导致人们对雾霾的发生不完全了解。在本研究中，评估了在278 K和308 K的烟雾室中，甲苯，甲苯/ NO，甲苯/ O ₃和反应系统中VOC最重要的烃之一甲苯的光化学转化长达4天。结果表明，NO和O _3的加入促进了甲苯的转化。在278 K和308 K下在甲苯反应系统中评估的甲苯一级动力学速率常数分别为0.12和0.19天^-1， 分别。在甲苯/ NO中评估的甲苯二阶动力学速率常数为0.1×10 ^-13  cm ³ 分子^-1 天^-1（在278 K下）和0.9×10 ^-13  cm ³分子^-1 天^-1（在278上）308 K）和甲苯/ O ₃反应体系中的 分子分别为0.06×10 ^-12  cm ³分子^-1 天^-1（在278 K下）和0.11×10 ^-12  cm ³ 分子^-1 天^{-1 -1}（在308 K时）。当与甲苯/ NO系统相比时，对于甲苯/ O ₃系统，在278 K和308 K之间获得的二级动力学速率常数的小差异表明O ₃对温度的反应敏感性降低。通过正离子大气压光电离（+ APPI）结合傅里叶变换离子回旋加速器共振，鉴定了数十种最多包含O ₆杂原子的大分子产物质谱（FT-ICR MS），双键当量最高为18，碳数分别在12-38之间。本文介绍的发现可能为甲苯的光化学反应过程及其在环境空气中的转化提供新的思路。