In-situ growing Ni₂P on CdS@g-C₃N₄ composites for highly efficient synergistically photocatalytic H₂ evolution and antibiotic degradation

Achieving simultaneous photocatalytic H₂ evolution and antibiotic degradation is ideal but challenging. Herein, IS-Ni₂P/CdS/CN ternary composites was elaborately constructed by electrostatic self-assembly followed by in-situ growth of Ni₂P method. The IS-Ni₂P/CdS/CN exhibit extremely high H₂ yield and achieve synergistic degradation of multiple antibiotic contaminants (323 μmol g ^{− 1} h ^{− 1} for H₂ yield and 72 % for tetracycline hydrochloride synergistic degradation). Interestingly, for the synergistic mechanism, it is found that antibiotic molecules can serve as electron donors to promote the separation of carriers, thus remarkably improving H₂ yield. More notably, the electron-donating capacity of antibiotic molecules dictates the synergistic efficiency, that is, the stronger the electron-donating capacity of antibiotic molecules, the more favorable it is for enhancing synergistic efficiency. Besides, experimental and DFT calculation demonstrate that the exceptional photocatalytic activity of IS-Ni₂P/CdS/CN is ascribed to the combined effect of the induced internal electric field, and the improved interfacial contact by the in-situ grown Ni₂P cocatalyst, thus substantially accelerating carriers transport. Our work provides an idea for simultaneous photocatalytic H₂ evolution and pollutants degradation. © 2024 Elsevier B.V. All rights reserved.