Nitric oxide, ammonia and volatile organic compounds are common air pollutants which need to be removed for health security. To reach ultra-low emission standards, photocatalysis has emerged as a environmentally benign and efficient method to lower pollutant levels. Understanding the pollutant removal mechanism is necessary to optimize the design of the photocatalyst. Here, we review air purification by gas–solid photooxidation. We discuss the role of light absorption, charge carrier separation and active sites for designing the photocatalyst. We present reaction processes with emphasis on the adsorption and activation of reactants, the formation of intermediates and byproducts, and the conversion pathways towards the final product. Perspectives of photocatalytic degradation in suppressing by-products, inhibiting deactivation and dealing with pollutant mixtures are discussed.

一氧化氮、氨和挥发性有机化合物是常见的空气污染物，需要去除以确保健康安全。为了达到超低排放标准，光催化已成为一种环境友好且有效的降低污染物水平的方法。了解污染物去除机制对于优化光催化剂的设计是必要的。在这里，我们回顾了通过气固光氧化净化空气。我们讨论了光吸收、电荷载流子分离和活性位点在设计光催化剂中的作用。我们介绍了反应过程，重点是反应物的吸附和活化、中间体和副产物的形成以及最终产物的转化途径。光催化降解抑制副产物的前景，