CdSIn bond bridging nanoflower shaped In_2.77S₄/Cd_0.5Zn_0.5S heterojunction modulation interface charge promotes...

Photocatalytic CO₂ reduction into solar fuels offers a promising strategy to alleviate energy shortages and environmental issues. Nevertheless, this process is severely restricted by rapid photocarrier recombination and insufficient CO₂ activation capacity. Herein, a novel Z-scheme heterojunction In_2.77S₄/Cd_0.5Zn_0.5S with unique CdSIn interfacial bonds was rationally fabricated via the in-situ growth of Cd_0.5Zn_0.5S nanospheres on flower-like In_2.77S₄ nanoflowers. The formed CdSIn chemical bonds acted as high-speed electron transfer bridges, which steered photogenerated electrons towards ZnCd heteronuclear bimetallic sites through the Z-scheme charge transfer pathway and provided sufficient electrons for CO₂ reduction. Meanwhile, the strong covalent coupling between two components reduced the surface charge density of Cd_0.5Zn_0.5S, effectively lowering the formation energy barriers of key C₂ intermediates (*CO and *OCCO) and greatly promoting CO₂ adsorption and activation. Benefiting from the above advantages, the flower-like In_2.77S₄/Cd_0.5Zn_0.5S heterojunction delivered remarkable photothermal CO₂ photoreduction performance. For the optimal sample, the evolution rates of CO and C₂H₄ reached 100.95 μmol·g^-1·h^-1 and 18.43 μmol·g^-1·h^-1, respectively. These values were 14.87 and 8.53 times higher than those of Cd_0.5Zn_0.5S, as well as far superior to In_2.77S₄. This work provided a feasible and innovative route for the construction of high-efficiency photocatalysts towards selective CO₂ conversion into high-value C₂ products.