Surfactant-free 2D/2D Pd/g-C₃N₄ for enhanced photocatalytic CO₂ reduction

Two-dimensional (2D) photocatalysts loaded with metal nanosheets, possessing enhanced charge transfer efficiency between the large 2D/2D interfaces, exhibit unprecedented advantages in photocatalysis. However, the inhibitory influence of surfactants on catalysis limits their applications. Herein, surfactant-free Pd nanosheets (Pd NSs) with tunable size are in situ anchored on graphitic carbon nitride nanosheets (CNs). PdCl42- is used as the precursor and CO is used as both reducing and structure-directing agents. Moreover, by using the same strategy, surfactant-free Pd NSs can also be anchored onto other 2D materials, such as TiO2 nanoplates and graphene oxide (GO). Importantly, the obtained surface-clean Pd NSs/CN exhibits improved visible-light photocatalytic activity toward CO2 reduction to CO and CH4 compared with surfactant-coated Pd NSs/CN. This work affords a general and facile method for fabricating nanosheet supported surfactant-free 2D metals, and reveals the negative effects of surfactant on photocatalytic performance.