Yan Wu1, Hou Wang2, Wenguang Tu1, Yue Liu1, Yong Zen Tan1, Xingzhong Yuan3, Jia Wei Chew4. 1. School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Singapore. 2. School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Singapore; College of Environmental Science and Engineering, Hunan University, Changsha 410082, China. Electronic address: huankewanghou024@163.com. 3. College of Environmental Science and Engineering, Hunan University, Changsha 410082, China. 4. School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Singapore; Singapore Membrane Technology Center, Nanyang Environment and Water Research Institute, Nanyang Technological University, Singapore 639798, Singapore. Electronic address: JChew@ntu.edu.sg.
Abstract
Materials of perovskite-type structure have attracted considerable attention for their applications in photocatalysis. In this study, a novel composite of p-type LaFeO3 microsphere coated with n-type nanosized graphitic carbon nitride nanosheets was constructed by the quasi-polymeric calcination method with the aid of electrostatic self-assembly interaction. Results indicate that the LaFeO3/g-C3N4p-n heterostructured photocatalyst obtained, in contrast to the pure constituents, enabled improved visible-light absorption, and more efficient separation and migration of charge carriers via solid p-n heterojunction interfacial effect. Correspondingly, the LaFeO3/g-C3N4 composite allowed for higher visible-light-responsive photocatalytic activity for the degradation of Brilliant Blue, which was 16.9 and 7.8 times that of pristine g-C3N4 and LaFeO3, respectively. The photocatalytic degradation of Brilliant Blue was ascribed to the combined contributions of the photogenerated holes (h+), superoxide radicals (O2-) and hydroxyl radicals (OH). Based on solid p-n heterojunction interfacial interaction, a Z-scheme charge carrier transfer pathway integrated with the dye-sensitization effect is proposed as the underlying mechanism of the photocatalytic reaction process. Therefore, we believe that the perovskite-type LaFeO3/g-C3N4 Z-scheme photcatalyst promotes the development of photocatalysis and holds much promise for environmental remediation.
Materials of perovskite-type structure have attracted considerable attention for their applications in photocatalysis. In this study, a novel composite of p-type LaFeO3 microspn>here coated with n-typn>e nanosized graphitic n>an class="Chemical">carbon nitride nanosheets was constructed by the quasi-polymeric calcination method with the aid of electrostatic self-assembly interaction. Results indicate that the LaFeO3/g-C3N4p-n heterostructured photocatalyst obtained, in contrast to the pure constituents, enabled improved visible-light absorption, and more efficient separation and migration of charge carriers via solid p-n heterojunction interfacial effect. Correspondingly, the LaFeO3/g-C3N4 composite allowed for higher visible-light-responsive photocatalytic activity for the degradation of Brilliant Blue, which was 16.9 and 7.8 times that of pristine g-C3N4 and LaFeO3, respectively. The photocatalytic degradation of Brilliant Blue was ascribed to the combined contributions of the photogenerated holes (h+), superoxide radicals (O2-) and hydroxyl radicals (OH). Based on solid p-n heterojunction interfacial interaction, a Z-scheme charge carrier transfer pathway integrated with the dye-sensitization effect is proposed as the underlying mechanism of the photocatalytic reaction process. Therefore, we believe that the perovskite-type LaFeO3/g-C3N4 Z-scheme photcatalyst promotes the development of photocatalysis and holds much promise for environmental remediation.