Abstract Despite the growing share of hybrid vehicles in worldwide vehicle fleet, the impact of battery/engine switch on secondary pollutant precursors formation remains poorly understood. We herein identify the species to be removed primarily from the exhaust of hybrid vehicles to minimize secondary pollutants formation. Pollutants from a conventional (thermal) and a hybrid vehicle are herein evaluated in a chassis dynamometer bench by using two widely used driving cycles, WLTC and FTP75. Hybrid vehicle exhibits the lowest regulated emissions during all the different tests, except for NOx. The results reveal that low and cold start phases of the cycles contribute mainly to the ozone potential, although methane, butadiene and formaldehyde can be emitted at the tailpipe all along the driving cycle. We evidence for the first time a significant contribution of gas-phase reactions to butadiene and methane production inside the exhaust pipe, especially during warm restarts and accelerations. This study indicates that pollutant traps should target primarily monoaromatics which contribute typically to 40% of photochemical ozone creation and 50% to Secondary Organic Aerosols (SOA). However, the contribution of alkanes to ozone differs markedly for the hybrid vehicle, reflecting a different share of ozone production paths with respect to conventional vehicles.

中文翻译：

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通过识别汽油尾气中最有影响的挥发性排放物来最大程度地减少二次污染物的形成：车辆动力总成技术的影响

摘要 尽管混合动力汽车在全球车队中的份额不断增加，但电池/发动机开关对二次污染物前体形成的影响仍然知之甚少。我们在此确定了主要从混合动力汽车尾气中去除的物质，以最大限度地减少二次污染物的形成。来自传统（热）和混合动力车辆的污染物在这里通过使用两个广泛使用的驱动循环，WLTC 和 FTP75 在底盘测功机台架上进行评估。在所有不同的测试中，混合动力汽车的排放量最低，但 NOx 除外。结果表明，循环的低启动阶段和冷启动阶段主要对臭氧势有贡献，尽管在整个驾驶循环中，尾气管处会排放甲烷、丁二烯和甲醛。我们首次证明了气相反应对排气管内丁二烯和甲烷生成的显着贡献，尤其是在暖启动和加速期间。这项研究表明，污染物捕集器应主要针对单芳烃，它们通常对光化学臭氧产生的 40% 有贡献，对二次有机气溶胶 (SOA) 有 50% 的贡献。然而，混合动力汽车的烷烃对臭氧的贡献显着不同，反映了与传统汽车相比，臭氧产生路径的不同份额。这项研究表明，污染物捕集器应主要针对单芳烃，它们通常对光化学臭氧产生的 40% 有贡献，对二次有机气溶胶 (SOA) 贡献 50%。然而，混合动力汽车的烷烃对臭氧的贡献显着不同，反映了与传统汽车相比，臭氧产生路径的不同份额。这项研究表明，污染物捕集器应主要针对单芳烃，它们通常对光化学臭氧产生的 40% 有贡献，对二次有机气溶胶 (SOA) 贡献 50%。然而，混合动力汽车的烷烃对臭氧的贡献显着不同，反映了与传统汽车相比，臭氧产生路径的不同份额。