Nitrogen vacancy-modified g-C3N4 nanosheets controlled by deep eutectic solvents for highly efficient photocatalytic atrazine degradation: Non-radical dominated holes oxidation

Metal-free photocatalysts like graphitic carbon nitride (g-C3N4) 3 N 4 ) can have their electronic structures altered by vacancy defect engineering, greatly increasing their catalytic activity. Here, we have synthesized nitrogen vacancy mediated carbon nitride (DCNA) modified by deep eutectic solvents for the first time, DCNA showed 4.93- fold improvement compared to pristine g-C3N4 3 N 4 towards photocatalytic degradation of atrazine (ATZ). Besides, we have revealed the role of photogenic holes as the main active species for the photocatalytic degradation of ATZ. This improvement is attributed to the increased nitrogen vacancy, which increases the adsorption of N-H on the ATZ side chain, accelerates the process of photoelectron and hole separation, and allows more holes to participate in ATZ degradation. Moreover, the wheat growth toxicity test significantly reduced the degradation byproducts' toxicity. This study provides an effective method for preparing environmentally friendly metal-free photocatalysts with high catalytic performance.