Constructing S-scheme CeO₂/CN heterojunction for high efficiency light-induced photothermal synergistic catalytic degradation of gaseous formaldehyde under visible light irradiation

An efficient light-induced photothermal synergistic strategy was proposed to achieve efficient photocatalytic degradation of gaseous formaldehyde based on an innovative 0D/2D S-scheme CeO2/CN heterojunction. The S-scheme photocatalyst shows excellent photocatalytic formaldehyde degradation activity under visible light irradiation, which can be attributed to the synergistic effect of the following aspects: (I) the S-scheme heterojunction: photogenerated carriers with stronger redox ability; (II) the increased interface migration channel and reduced interface contact resistance facilitated the migration and separation of photogenerated carriers; (III) light-induced photothermal effect improved the temperature of photocatalyst. The optimal photocatalytic HCHO degradation rate of the S-scheme CeO2/CN-1:1 is 20.3, 4.7 and 1.8 times that of CN, CN-1:1 and traditional type-II CeO2@CN-1:1, respectively. Therefore, this work not only provides an efficient strategy for elimination of formaldehyde pollutants, but also provides new ideas for the design of efficient photocatalysts for other kinds of VOCs pollutants in the future.