Progress and prospects of photocatalytic conversion of low-concentration NOx

NOx can cause severe environmental problems such as acid rain and photochemical smog, endangering human health and the living environment. Among them, NO pollution accounts for about 95%. NO can exist stably in the air for a long time when the concentration is lower than the ppm level. Therefore, the conversion of low concentration of NO has attracted more and more attention. However, traditional physical or chemical methods are difficult to deal with low concentration of NO, having high requirements on equipment and being not cost-effective. Semiconductor photocatalytic technology can convert low concentration of NO into non-toxic products and reduce its harm. This work briefly surveys the commonly used materials, modification methods, and mechanisms for semiconductor photocatalytic conversion of low concentration of NO. In addition, the challenges and prospects of ppb level of NO treatment are also discussed, aiming to promote the development of semiconductor photocatalytic conversion of NO.