Developing a high-quality photoelectrode for photoelectrochemical applications is still an ongoing challenge. In this study, we prepared the g-C_(3)N_(4) film on the indium tin oxide(ITO) glass through conventional co...Developing a high-quality photoelectrode for photoelectrochemical applications is still an ongoing challenge. In this study, we prepared the g-C_(3)N_(4) film on the indium tin oxide(ITO) glass through conventional coating, liquid-based growth, in-situ calcination, and vapor deposition methods, respectively. These electrodes were characterized and used as photoanodes to degrade methylene blue(MB) in water. Among these methods, the in-situ calcination method was most appropriate for preparing the continuous and organized g-C_(3)N_(4) film electrodes with uniform g-C_(3)N_(4) coverage and strong adhesion to the ITO substrate.It also had the highest activity in the photocatalytic(PC), electrochemical(EC), and photoelectrocatalytic(PEC) degradation processes of MB. In the PEC reaction, at an applied potential of 1.0 V and a light intensity of 0.96 W/cm^(2), the removal rate of MB was 62.5%, which was much higher than those in the PC and EC reactions. The high degradation rate was due to the synergistic effect of PEC degradation, wherein the PC and EC reactions promote and optimize each other. In the PC reaction, MB was degraded by-CH_(3) elimination, while the EC degradation pathway mainly included the conversion of sulfhydryl into sulfoxide and the opening of the central aromatic ring. Both methyl loss and aromatic ring opening occurred in the PEC reaction. Moreover, some monocyclic compounds were formed, and MB showed more complete degradation in the PEC reaction.展开更多
基金financial support from the National Natural Science Foundation of China(No.51978658)。
文摘Developing a high-quality photoelectrode for photoelectrochemical applications is still an ongoing challenge. In this study, we prepared the g-C_(3)N_(4) film on the indium tin oxide(ITO) glass through conventional coating, liquid-based growth, in-situ calcination, and vapor deposition methods, respectively. These electrodes were characterized and used as photoanodes to degrade methylene blue(MB) in water. Among these methods, the in-situ calcination method was most appropriate for preparing the continuous and organized g-C_(3)N_(4) film electrodes with uniform g-C_(3)N_(4) coverage and strong adhesion to the ITO substrate.It also had the highest activity in the photocatalytic(PC), electrochemical(EC), and photoelectrocatalytic(PEC) degradation processes of MB. In the PEC reaction, at an applied potential of 1.0 V and a light intensity of 0.96 W/cm^(2), the removal rate of MB was 62.5%, which was much higher than those in the PC and EC reactions. The high degradation rate was due to the synergistic effect of PEC degradation, wherein the PC and EC reactions promote and optimize each other. In the PC reaction, MB was degraded by-CH_(3) elimination, while the EC degradation pathway mainly included the conversion of sulfhydryl into sulfoxide and the opening of the central aromatic ring. Both methyl loss and aromatic ring opening occurred in the PEC reaction. Moreover, some monocyclic compounds were formed, and MB showed more complete degradation in the PEC reaction.
