Visible light photocatalytic activity of TiO2 with carbon-fluorine heteroatoms simultaneously introduced by CF4 plasma

• Published in: The Korean journal of chemical engineering Vol. 39; no. 12; pp. 3334 - 3342
• Main Authors: Lee, Raneun, Lim, Chaehun, Lee, Hyeryeon, Kim, Seokjin, Lee, Young-Seak
• Format: Journal Article
• Language: English
• Published: New York Springer US 01-12-2022; Springer Nature B.V; 한국화학공학회
• Subjects: Biotechnology; Carbon; Catalysis; Catalytic activity; Chemistry; Chemistry and Materials Science; Dyes; Environmental Engineering; Fluorine; Free radicals; Industrial Chemistry/Chemical Engineering; Light irradiation; Materials Science; Methylene blue; Photocatalysis; Photodegradation; Plasma etching; Rate constants; Rhodamine; Titanium dioxide; 화학공학; Plasma; CF; Titanium Dioxide; Photocatalyst; Photocatalytic Activity
• ISSN: 0256-1115; 1975-7220
• DOI: 10.1007/s11814-022-1128-x

CF
4
plasma treatment is performed on commercial TiO
2
to improve the photocatalytic efficiency. The CF
4
plasma treatment is a facile and fast method for simultaneous introduction of carbon and fluorine atoms onto TiO
2
. Photodegradation of rhodamine B, methyl orange, and methylene blue is carried out under solar light irradiation to determine its CF
4
plasma treatment effect. The dye removal of commercial TiO
2
to rhodamine B, methyl orange, and methylene blue is 60.0, 18.9, and 49.2%, respectively, whereas TiO
2
treated with CF
4
plasma for 50 min is 93.5, 71.0, and 88.6% for rhodamine B, methyl orange, and methylene blue, respectively. In addition, the photodegradation rate constants of TiO
2
treated with CF
4
plasma for 50 min were 0.0135, 0.0083, and 0.0129 min
−1
for rhodamine B, methyl orange, and methylene blue, respectively, which are up to 7.5 times higher than that of untreated TiO
2
(0.0049, 0.0011, and 0.0039 min
−1
). This improvement is attributed to the increase in oxygen vacancies by the introduction of carbon atoms into TiO
2
using CF
4
plasma treatment. In addition, the F
−
ions physically adsorbed to the TiO
2
surface promote the formation of hydroxyl free radicals, enabling effective decomposition of various dyes.