TiO2 nanorod arrays decorated by nitrogen-doped carbon and g-C3N4 with enhanced photoelectrocatalytic activity

• DOI: 10.1016/j.apsusc.2020.146219
• Publication Date: 2020-03-28T00:08:29Z
• Authors: Kelei Huang; Chunhu Li; Xiuli Zhang; Xiangchao Meng; Liang Wang; Wentai Wang; Zizhen Li
• Keywords: 02 engineering and technology; 0210 nano-technology

Abstract A novel route was proposed for constructing nitrogen-doped carbon (CN) interfacial nano-layer derived from polydopamine to anchor graphitic carbon nitride (g-C3N4) onto TiO2 nanorod arrays (TNR) via solvothermal growth and annealed process. The prepared TNR@CN-C3N4/FTO photoanode with shell-core heterostructure exhibited the excellent visible light photosensitization and significantly enhanced photoelectrocatalytic (PEC) degradation of pollutant. The results of characterizations and photoelectrochemical measurements proved that CN bonded with TiO2 via C-O-Ti to enrich the absorption of visible light. In addition, CN reinforced the contact between TiO2 and g-C3N4, and improved the electrical conductivity. These synergistic effects resulted in the acceleration of photoexcited electrons separation/transfer and reactive species production. Ternary TNR@CN-C3N4/FTO photoelectrode showed the highest photocurrent density (0.45 mA/cm2 at 0.6 V) and the best PEC degradation rate (94.2% at 1.5 V) of methyl orange, which were higher than that of TNR-C3N4/FTO without CN layer by a factor of 2.4 and 0.3, respectively. It was proved that the holes were the main reactive species in PEC degradation. This work provided a new pathway for the development of g-C3N4 based heterostructure in photoelectrocatalytic removal pollutants.