One-step synthesis of MnOx/g-C3N4 nanocomposites for enhancing the visible light photoelectrochemical oxidation performance

Here, we report enhancement of the photoelectrochemical (PEC) performance of MnOx/graphite-like carbon nitride (g-C3N4) nanocomposites synthesized by one-step thermal decomposition for degradation of clofibric acid (CA). MnOx showed enhanced broadband ultraviolet-visible light regions, efficient charge generation-separation, and enhanced PEC performance when combined with g-C3N4. Photogenerated holes can be efficiently captured by introducing Mn2+/Mn3+/Mn4+ valence band transitions. In addition to a good visible-light response, the MnOx/g-C3N4-10 (g-C3N4 with 10% Mn(NO3)(2)6H(2)O) photoanode showed enhanced photocurrent density of 0.03 x 10(-3) A cm(-2) at 0.63 V vs. Ag/AgCl, which was approximately 100 times that of pristine g-C3N4. The superoxide radical and positive holes played dominant roles in PEC degradation of CA. The MnOx/gC(3)N(4)-10 photoanode showed the highest photoelectrocatalytic performance under acidic conditions because of electrostatic attraction between the electrode and CA. The CA degradation ratio using the MnOx/g-C3N4-10 photoanode was 100% under visible light in 6 h at pH = 3. This work provides a simple and sustainable strategy to modify g-C3N4 for captured holes to improve PEC degradation of CA, and it is promising for application to different materials in a variety of fields.