Boosting the Visible-Light Photoactivity of BiOCl/BiVO4/N-GQD Ternary Heterojunctions Based on Internal Z-Scheme Charge Transfer of N-GQDs: Simultaneous Band Gap Narrowing and Carrier Lifetime Prolonging

The efficient separation of photogenerated electron–hole pairs in photoactive materials is highly desired, allowing their transfer to specific sites for undergoing redox reaction in various applications. The construction of ternary heterojunctions is a practical strategy to enhance the migration of photogenerated electron that realizes the synergistic effect of multicomponents rather than the simple overlay of single component. Here, we demonstrate an available way to fabricate new BiOCl/BiVO4/nitrogen-doped graphene quantum dot (N-GQD) ternary heterojunctions that exhibit higher efficiency in charge separation than any binary heterojunction or pure material under visible-light irradiation. UV–vis diffuse reflectance spectroscopy demonstrated that the proposed BiOCl/BiVO4/N-GQD ternary heterojunctions possess the narrower band gap energy. More importantly, the ternary heterojunctions reveal the prolonged lifetime of photogenerated charges and enhanced the separation efficiency of photogenerated electron–h...