One-step fabrication of unique 3D/2D S, O-doped g-C₃N₄ S-scheme isotype heterojunction for boosting CO₂ photoreduction

Solar irradiation-based CO₂ conversion to energy-rich products is an efficient way to reduce excessive CO₂ emissions and solve resource depletion. Unfortunately, achieving a cost-effective and dependable method for converting CO₂ is still a significant challenge. Here, we introduce a hydrothermal approach followed by calcination to design a new-fashioned 3D S-doped g-C₃N₄/2D O-doped g-C₃N₄ (3D/2D SOCN) based step-scheme (S-scheme) heterojunction as an efficient photocatalysts for CO₂ reduction. The adjusted sample demonstrated significantly greater CO₂ photoreduction conversion rates compared to the blank control, including 3D S-doped g-C₃N₄ (3D SCN), 2D O-doped g-C₃N₄ (2D OCN), and bulk g-C₃N₄ (CN). The exceptional photocatalytic performance can be ascribed to multiple factors, including the S-Scheme isotype heterojunction that suppresses the recombination of photogenerated charge carriers, the material's high specific surface areas, which highly enhance the abundance of active sites, and the synergistic effect of the heteroatom as a dopant. The validity of the S-Scheme photogenerated charge transfer process is supported by measuring the work function and electron paramagnetic resonance (EPR). This research presents a practical method for fabricating multi non-metal-doped S-scheme isotype heterojunction photocatalysts that display remarkable efficiency for solar fuel conversion.