Polymerization synthesis of semi-coke activated carbon modified carbon nitride nanoscrolls with boosted photocatalytic H₂ production

The porous semi-coke activated carbon (SAC) was derived from solid waste semi-coke (SC) powder by an activation process. Subsequently, a highly efficient photocatalyst (SAC/CN) was prepared by loading SAC onto carbon nitride (CN). The SAC/CN composite exhibited an increased surface area, well-dispersed layered CN, abundant delocalization electrons, redshift in light absorption, and a more negative conduction band (CB) edge. The optimal 0.7 %SAC/CN₆₀₀ sample exhibited the highest H₂ production rate of 12.86 mmol·h⁻¹·g⁻¹, which is 8.0-fold higher than that of pristine CN. The SAC/CN photocatalysts also demonstrated excellent stability and reusability. Photoluminescence (PL) and electrochemical measurements indicated enhanced charge separation/transfer efficiency in the SAC/CN composite. These findings propose a novel approach for recycling of coal chemical solid waste coupled with CN photocatalysts to achieve efficient solar-to-chemical energy conversion.