Abstract
Photocatalysis is regarded as a promising technology for removal of nitrogen oxide (NO), however, the low photocatalytic efficiencies under visible light irradiation and the deactivation of the photocatalyst are as yet the significant issues that should be addressed. In this work, visible-light-driven Bi2Ti2O7/CaTiO3 heterojunction composites were synthesized by a facile in-situ hydrothermal method. The Bi2Ti2O7/CaTiO3 composites displayed superior visible light photocatalytic activity than pure CaTiO3 and pure Bi2Ti2O7 in the removal of NO at the 600 ppb level in air. Among all the composites, Bi2Ti2O7/CaTiO3 containing 20 wt% Bi2Ti2O7 exhibited the best photocatalytic activity, achieving a maximum removal efficiency of 59%. The improved photocatalytic performance is mainly attributed to the strong visible-light-absorbing ability, the presence of an appropriate density of oxygen vacancy defects and the formation of heterojunction between CaTiO3 and Bi2Ti2O7, resulting in an efficient charge separation at the interface as proven by photoluminescence (PL) and photo-induced current measurements. According to trapping experiments and spin-trapping ESR analysis, the •O2− and h+ are the principal reactive species involved in the photocatalytic NO removal. In addition, the as-obtained Bi2Ti2O7/CaTiO3 composite showed good chemical stability, which is beneficial for practical applications in air pollution removal.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.