TY - JOUR
T1 - Remarkable Enhancement of Photocatalytic Activity of High-Energy TiO2 Nanocrystals for NO Oxidation through Surface Defluorination
AU - Wu, Xiaofeng
AU - Zhou, Jie
AU - Tan, Qiuyan
AU - Li, Kaining
AU - Li, Qin
AU - Correia Carabineiro, Sónia A.
AU - Lv, Kangle
N1 - info:eu-repo/grantAgreement/FCT/6817 - DCRRNI ID/LA%2FP%2F0008%2F2020/PT#
info:eu-repo/grantAgreement/FCT/6817 - DCRRNI ID/UIDB%2F50006%2F2020/PT#
Funding Information:
This work was supported by the National Natural Science Foundation of China (51672312 and 21972171), joint supported by Hubei Provincial Natural Science Foundation and Huangshi of China (2022CFD001), the Fundamental Research Funds for the Central Universities of South-Central Minzu University (CZP22001 and CZZ21012).
Publisher Copyright:
© 2024 American Chemical Society.
PY - 2024/3/6
Y1 - 2024/3/6
N2 - The superior photocatalytic activity of TiO2 nanocrystals with exposed high-energy (001) facets, achieved through the use of hydrofluoric acid as a shape-directing reagent, is widely reported. However, in this study, we report for the first time the detrimental effect of surface fluorination on the photoreactivity of high-energy faceted TiO2 nanocrystals towards NO oxidation (resulting in a NO removal rate of only 5.9%). This study aims to overcome this limitation by exploring surface defluorination as an effective strategy to enhance the photocatalytic oxidation of NO on TiO2 nanocrystals enclosed with (001) facets. We found that surface defluorination, achieved through either NaOH washing (resulting in an improved NO removal rate of 23.2%) or calcination (yielding an enhanced NO removal rate of 52%), leads to a large increase in the photocatalytic oxidation of NO on TiO2 nanocrystals with enclosed (001) facets. Defluorination processes stimulate charge separation, effectively retarding recombination and significantly promoting the production of reactive oxygen species, including superoxide radicals (·O2-), singlet oxygen (1O2), and hydroxyl radicals (·OH). Both in situ diffuse reflectance infrared Fourier-transform spectroscopy and density functional theory calculations confirm the higher adsorption of NO after defluorination, thus facilitating the oxidation of NO on TiO2 nanocrystals.
AB - The superior photocatalytic activity of TiO2 nanocrystals with exposed high-energy (001) facets, achieved through the use of hydrofluoric acid as a shape-directing reagent, is widely reported. However, in this study, we report for the first time the detrimental effect of surface fluorination on the photoreactivity of high-energy faceted TiO2 nanocrystals towards NO oxidation (resulting in a NO removal rate of only 5.9%). This study aims to overcome this limitation by exploring surface defluorination as an effective strategy to enhance the photocatalytic oxidation of NO on TiO2 nanocrystals enclosed with (001) facets. We found that surface defluorination, achieved through either NaOH washing (resulting in an improved NO removal rate of 23.2%) or calcination (yielding an enhanced NO removal rate of 52%), leads to a large increase in the photocatalytic oxidation of NO on TiO2 nanocrystals with enclosed (001) facets. Defluorination processes stimulate charge separation, effectively retarding recombination and significantly promoting the production of reactive oxygen species, including superoxide radicals (·O2-), singlet oxygen (1O2), and hydroxyl radicals (·OH). Both in situ diffuse reflectance infrared Fourier-transform spectroscopy and density functional theory calculations confirm the higher adsorption of NO after defluorination, thus facilitating the oxidation of NO on TiO2 nanocrystals.
KW - adsorption
KW - fluorine
KW - NO
KW - photocatalysis
KW - TiO
UR - http://www.scopus.com/inward/record.url?scp=85186230732&partnerID=8YFLogxK
U2 - 10.1021/acsami.3c16994
DO - 10.1021/acsami.3c16994
M3 - Article
C2 - 38386611
AN - SCOPUS:85186230732
SN - 1944-8244
VL - 16
SP - 11479
EP - 11488
JO - ACS Applied Materials and Interfaces
JF - ACS Applied Materials and Interfaces
IS - 9
ER -