Enhanced visible light photocatalytic activity of N and Ag doped and co-doped TiO2 synthesized by using an in-situ solvothermal method for gas phase ammonia removal

Journal article

Authors/Editors

SIRILUK CHIARAKORN

Strategic Research Themes

Sustainable Energy & Environment (Strategic Research Themes)

Publication Details

Author list: Sirivallop, Adilah; Areerob, Thanita; Chiarakorn, Siriluk;

Publisher: MDPI

Publication year: 2020

Volume number: 10

Issue number: 2

ISSN: 2073-4344

eISSN: 2073-4344

URL: https://www.scopus.com/inward/record.uri?eid=2-s2.0-85079894951&doi=10.3390%2fcatal10020251&partnerID=40&md5=2ee50594a742da4a80447395724ec329

Languages: English-Great Britain (EN-GB)

View in Web of Science | View on publisher site | View citing articles in Web of Science

Abstract

Single doping and co-doping of N and Ag on TiO2 were successfully prepared by using an in-situ solvothermal method and their structural properties and chemical compositions were characterized. The results indicated that all photocatalysts displayed in TiO2 anatase crystal phase, and a small mesoporous structure was observed in the doped materials. The main roles of N and Ag on the property and photocatalytic activity of TiO2 were different. The N doping has significantly enhanced homogenous surface morphology and specific surface area of the photocatalyst. While Ag doping was narrowing the band gap energy, extending light absorption toward a visible region by surface plasmon resonance as well as delaying the recombination rate of electron and hole of TiO2. The existence of N in TiO2 lattice was observed in two structural linkages such as substitutional nitrogen (Ti-O-N) and interstitial nitrogen (O-Ti-N). Silver species could be in the form of Ag0 and Ag2O. The photocatalytic performance of the photocatalysts coated on stainless steel mesh was investigated by the degradation of aqueous MB and gas phase NH3 under visible LED light illumination for three recycling runs. The highest photocatalytic activity and recyclability were reached in 5% N/Ag-TiO2 showing the efficiency of 98.82% for methylene blue (MB) dye degradation and 37.5% for NH3 removal in 6 h, which was 2.7 and 4.3 times, respectively. This is greater than that of pure TiO2. This was due to the synergistic effect of N and Ag doping. © 2020 by the authors. Licensee MDPI, Basel, Switzerland.

Keywords

Ammonia removal, In-situ synthesis, Silver and nitrogen co-doping, Visible light absorption