Activated carbon/g-C3N4 /H2O2 system with enhanced photocatalytic activity for Rhodamine-B degradation under the visible light

In this study, activated carbon/g-C3N4 photocatalyst (BC/CN) was successfully prepared by a facile calcination method from activated carbons derived from banana peels and urea. As a result, the morphology of BC/CN consisted of the activated carbons highly dispersed on the g-C3N4 matrix. The advanced oxidation process of BC/CN and hydogen peroxide exhibits a better catalytic activity towards Rhdamine-B degradation in visible-light region than those of the pristine g-C3N4 or BC with hydrogen peroxide. The grafting of activated carbon to g-C3N4 enhanced the electron transfer efficiency and suppressed the photoinduced electron-hole recombination. Initial TOC was about 650 mg/L; however, it decreased by 93% to 60 mg/L after 60 min treating. After four cycles of experiments, the catalyst BC/CN still presented high activity for the degradation of RhB. In addition, all N-deethylation intermediates and several small molecular products were separated and identified by LC/MS method. Based on the analytical results, a possible mechanism of photocatalytic degradation was proposed. This work demonstrates a facile and efficient approach to improving the performance of g-C3N4-based catalysts.