TY - JOUR

T1 - Visible light-driven novel Bi2Ti2O7/CaTiO3 composite photocatalyst with enhanced photocatalytic activity towards NO removal

AU - Shi, Menglin

AU - Rhimi, Baker

AU - Zhang, Ke

AU - Xu, Jingkun

AU - Bahnemann, Detlef W.

AU - Wang, Chuanyi

N1 - Funding Information: This work was supported by the National Natural Science Foundation of China (21976116), Shaanxi Science and Technology Program (2020KWZ-005), SAFEA of China (High-end Foreign Expert Project), and Alexander-von-Humboldt Foundation of Germany (Group-Linkage Program). Menglin Shi : Performing the experiments; Writing the initial draft, Baker Rhimi : Ideas; Supervision; Evolution of overarching research goals and aims. Detlef W. Bahnemann : Acquisition of the financial support for the project leading to this publication. Ke Zhang : Data/evidence collection. Jingkun Xu : Visualization, Investigation Chuanyi Wang : Coordination responsibility for the research activity planning and execution.

PY - 2021/7

Y1 - 2021/7

N2 - 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.

AB - 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.

KW - BiTiO

KW - CaTiO

KW - Heterojunction

KW - NO removal

KW - Oxygen vacancy

KW - Photocatalysis

UR - http://www.scopus.com/inward/record.url?scp=85101777924&partnerID=8YFLogxK

U2 - 10.1016/j.chemosphere.2021.130083

DO - 10.1016/j.chemosphere.2021.130083

M3 - Article

C2 - 33662727

AN - SCOPUS:85101777924

VL - 275

JO - Chemosphere

JF - Chemosphere

SN - 0045-6535

M1 - 130083

ER -