Constructing type II heterojunction of 2D/1D Pg-C₃N₄/Ag₃VO₄ nanocomposite with high interfacial charge separation for boosting photocatalytic CO₂ reduction under solar energy

The well-designed, template-free synthesis of 2D protonated g-C₃N₄ nanosheets (Pg-C₃N₄) coupled with novel 1D Ag₃VO₄ nanorods has been investigated to construct 2D/1D interface heterostructures with strong electrostatic interactions between the positively charged 2D Pg-C₃N₄ nanosheets and the negatively charged 1D Ag₃VO₄ nanorods. The coupling of Pg-C₃N₄ and Ag₃VO₄ with desirable characteristics resulted in a 2D/1D interface heterojunction with a type II charge carrier transfer mechanism, effectively maintaining and utilizing charge carriers. The 2D/1D Pg-C₃N₄/Ag₃VO₄ exhibited remarkable photocatalytic performance for CO₂ conversion with H₂O, resulting in maximum CH₄ and dimethyl ether (DME) production of 352.3 and 130.9 µmol/g-cat, respectively. A quantum yield of 0.23 % for CH₄ generation was achieved over the 2D/1D Pg-C₃N₄/Ag₃VO₄, which was 2.9 and 1.4 times higher than that of the Pg-C₃N₄ and Ag₃VO₄ samples, respectively. The improvement in photocatalytic performance primarily stems from the effective interaction between Pg-C₃N₄ and ternary Ag₃VO₄, leading to enhanced transfer and separation of photoinduced charge carriers through the creation of a type II heterojunction. The findings of this study are useful in designing template-free heterojunctions for photocatalytic CO₂ conversion and other solar energy applications.