A dual defect co-modified S-scheme heterojunction for boosting photocatalytic CO2 reduction coupled with tetracycline oxidation

To synchronously relieve energy shortage and wastewater remediation, herein, a dual-defect S-scheme heterojunction of I doped BiOBr modified N vacancy g-C3N4 (labeled as IB/CNx) was designed for simultaneously photocatalytic CO2 reduction coupled with tetracycline oxidation. The 70IB/CNx presented higher photocatalytic property for CO2 reduction coupled with TC removal than those of IB/CN, BiOBr/CNx, and BiOBr/CN. The improved photocatalytic activity was mainly attributed to the synergistic effect of doped I ions and N defects. Besides, such designed coupled reaction system presented much superior catalytic performance than those of two half-reactions, which achieved the full utilization of carriers. All in all, a dual-defect heterojunction enhanced a dual-function reaction system, in which the dual-defect active spots accelerated the transfer and separation of carriers, meanwhile, the dual-function reaction system realized the full utilization of the charges. This work highlighted the pivotal role of defect engineering to design efficient photocatalysts for environment and energy applications.