Hydrogen energy recovery via integrated antibiotics adsorption and photocatalytic degradation using mesoporous crystalline carbon nitride

Recovering H 2 energy from photocatalytic treatment of antibiotic-contaminated wastewater is considered an appealing strategy to mitigate the energy crisis and environmental issues. Herein, we present a hard-template-assisted molten-salt pyrolysis strategy to synthesize mesoporous carbon nitride with a highly crystalline structure (mpg-CCN), which was utilized for the integrated adsorption-photocatalytic degradation of FQs and the conversion of wastewater to hydrogen. mpg-CCN exhibits excellent photocatalytic performance with an H 2 evolution rate of 10,482.5 μmol/g and an optimal FQs degradation efficiency of 98.6% after 10 h of visible light irradiation. Experimental and theoretical calculation results disclose that the unique mesoporous structure of mpg-CCN improves the surface diffusion and adsorption of FQs. In addition, the highly crystalline structure provides unblocked channel for the transfer of photo-induced charges and accelerates both H 2 evolution and FQs degradation kinetics. Significantly, mpg-CCN can be effectively utilized for the ex-situ remediation of FQs, enabling recovery from the adsorbed pollutants via simple light treatment.