In-plane implanting carbon rings into carbon nitride to intrigue nonradical photodegradation

Photocatalysis has emerged as a prevailing and clean technology for water purification. In this work, we developed a facile approach for fabricating in-plane carbon/carbon nitride heterojunctions (CN-PDs) that induced 100% photodegradation of naproxen under visible light irradiation in a nonradical manner. Experimental and simulation results collectively revealed that the incorporated carbon rings in carbon nitride (CN) significantly accelerate the charge dynamics of excitons, leading to a higher concentration of hot carriers. In addition, a lower intersystem crossing energy barrier was observed for the unique nanostructure compared to pristine CN, enabling an efficient energy-transfer-mediated oxygen activation to selectively generate singlet oxygen. An optimized composition of carbon rings (CN-PDs0.1) enhanced the photodegradation of naproxen compared to CN. This study established the structure-activity relationships in selective photooxidation. The findings will benefit advanced design of high-performance nonmetal photocatalysts for organic wastewater treatment.