A band structure modulated 2D/2D ZnIn2S4@amorphous polymeric g-C3N4 S-scheme heterojunction for efficient photocatalytic reduction of CO2

Abstract

The use of solar energy to convert CO₂ into solar fuels via photocatalytic reduction represents a promising technology to address climate change. Herein, a unique S-scheme heterojunction of 2D/2D ZnIn₂S₄ nanosheets@amorphous polymeric carbon nitride (ZIS@APCN) is developed by in situ growth of ZnIn₂S₄ nanosheets onto two-dimensional porous amorphous polymeric carbon nitride with a finely tuned band structure for photocatalytic reduction of CO₂. Benefitting from ultra-thin two-dimensional and rigorous porous structures, notably enhanced CO₂ adsorption and increased active surface area are ensured. Moreover, the formed S-scheme heterojunction effectively promotes charge separation. The optimized S-scheme heterojunction of ZIS@APCN yields a CO production rate as high as 1425 μmol g⁻¹ h⁻¹, surpassing pure APCN by ∼7.34 times and ZIS by ∼3.98 times. This work introduces a new approach to develop S-scheme heterojunction for efficient CO₂ photoreduction by modulating the band structure.