La2Ti2O7 nanosheets modified by Pt quantum dots for efficient NO removal avoiding NO2 secondary pollutant

Li Lv; Hong-Dan Yang; Qi-Wen Chen; Huiqing Fan; Jian-Ping Zhou

doi:10.1016/j.envres.2023.115441

La₂Ti₂O₇ nanosheets modified by Pt quantum dots for efficient NO removal avoiding NO₂ secondary pollutant

Environ Res. 2023 Apr 15:223:115441. doi: 10.1016/j.envres.2023.115441. Epub 2023 Feb 8.

Authors

Li Lv¹, Hong-Dan Yang², Qi-Wen Chen², Huiqing Fan³, Jian-Ping Zhou⁴

Affiliations

¹ State Key Laboratory of Solidification Processing, School of Materials Science and Engineering, Northwestern Polytechnical University, Xi'an, 710072, People's Republic of China; School of Physics and Information Technology, Shaanxi Normal University, Xi'an, 710119, People's Republic of China.
² School of Physics and Information Technology, Shaanxi Normal University, Xi'an, 710119, People's Republic of China.
³ State Key Laboratory of Solidification Processing, School of Materials Science and Engineering, Northwestern Polytechnical University, Xi'an, 710072, People's Republic of China. Electronic address: hqfan@nwpu.edu.cn.
⁴ School of Physics and Information Technology, Shaanxi Normal University, Xi'an, 710119, People's Republic of China. Electronic address: zhoujp@snnu.edu.cn.

PMID: 36758917
DOI: 10.1016/j.envres.2023.115441

Abstract

Two-dimensional La₂Ti₂O₇ nanosheets with regular morphology and good dispersion were prepared by the hydrothermal method under a magnetic field. Zero-dimensional Pt quantum dots (Pt-QDs) were loaded on the La₂Ti₂O₇ nanosheets. The electron-hole separation and carrier transfer in the Pt-loaded La₂Ti₂O₇ nanosheets were significantly enhanced. The La₂Ti₂O₇ nanosheets loaded with 3 wt% Pt-QDs exhibit the largest NO removal efficiency of 51% and less than 3.2 ppb NO₂ intermediate pollutant in 30 min. The high photocatalytic ability was attributed to the surface plasmon resonance in Pt-QDs and the enhanced electron-hole separation. A large number of e^-, h⁺, •OH and •O₂^- active species were formed on the surface of Pt-loaded La₂Ti₂O₇ nanosheets under light irradiation. The conversion pathway from NO to NO₃^- was verified by the in situ diffuse reflectance infrared Fourier-transform spectroscopy and DFT calculation. This work supplies a feasible approach to responsive photocatalysts for efficient, stable, and selective NO removal avoiding the NO₂ secondary pollutant.

Keywords: Hydrothermal; La(2)Ti(2)O(7); Photocatalytic NO(x) removal; Quantum dots.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Light
Nitrogen Dioxide
Quantum Dots* / chemistry
Titanium

Substances

Nitrogen Dioxide
Titanium