TY - JOUR
T1 - Facile Surface Engineering of TiO2 Nanosheets for Enhanced Isopropanol Sensing under UV Irradiation
AU - Wu, Zeyi
AU - Su, Mengyao
AU - Song, Xiangyu
AU - Li, Denghua
AU - Li, Xinyuan
AU - Liu, Jiajia
AU - Zhang, Jiatao
N1 - Publisher Copyright:
© 2024 American Chemical Society.
PY - 2024/6/25
Y1 - 2024/6/25
N2 - Surface termination and defects of metal oxide semiconductors are crucial in the process of gas adsorption-desorption and signal transduction, thereby determining their sensing performance. Herein, a facile solvent-assisted surface engineering strategy was demonstrated to synthesize anatase TiO2 nanosheets (TNS) for an ultraviolet (UV) light-activated isopropanol (IPA) gas sensor. Surface-fluorinated TiO2 nanosheets (F-TNS) were first synthesized by the hydrofluoric acid-assisted hydrothermal method and followed by hydrothermally treating in Na2S solutions with different concentrations. The effect of the progressive removal of fluorides was discussed in detail based on X-ray photoelectron spectroscopy (XPS), diffuse reflectance spectroscopy (DRS), electrochemical impedance spectroscopy (EIS), and in situ Fourier transform infrared (FTIR) spectroscopy analyses. Compared with F-TNS, the chemiresistive sensor based on the TNS with a trace amount of fluorine exhibited a 324% increase in the sensitivity to 50 ppm of isopropanol at 50 °C under UV irradiation (λ = 365 nm, 30 mW/cm2), while it exhibited a 45% decrease in the recovery time. The enhanced isopropanol sensing performance could be attributed to the high surface area, rational surface terminations, oxygen vacancies, and UV photoexcited charge carriers, which further modulate the surface reaction and charge transfer. These findings offer a facile strategy for the rational design of oxide-based sensing materials, which help in understanding the function of surface terminations and defects in gas sensing.
AB - Surface termination and defects of metal oxide semiconductors are crucial in the process of gas adsorption-desorption and signal transduction, thereby determining their sensing performance. Herein, a facile solvent-assisted surface engineering strategy was demonstrated to synthesize anatase TiO2 nanosheets (TNS) for an ultraviolet (UV) light-activated isopropanol (IPA) gas sensor. Surface-fluorinated TiO2 nanosheets (F-TNS) were first synthesized by the hydrofluoric acid-assisted hydrothermal method and followed by hydrothermally treating in Na2S solutions with different concentrations. The effect of the progressive removal of fluorides was discussed in detail based on X-ray photoelectron spectroscopy (XPS), diffuse reflectance spectroscopy (DRS), electrochemical impedance spectroscopy (EIS), and in situ Fourier transform infrared (FTIR) spectroscopy analyses. Compared with F-TNS, the chemiresistive sensor based on the TNS with a trace amount of fluorine exhibited a 324% increase in the sensitivity to 50 ppm of isopropanol at 50 °C under UV irradiation (λ = 365 nm, 30 mW/cm2), while it exhibited a 45% decrease in the recovery time. The enhanced isopropanol sensing performance could be attributed to the high surface area, rational surface terminations, oxygen vacancies, and UV photoexcited charge carriers, which further modulate the surface reaction and charge transfer. These findings offer a facile strategy for the rational design of oxide-based sensing materials, which help in understanding the function of surface terminations and defects in gas sensing.
KW - TiO nanosheets
KW - fluoride
KW - isopropanol sensing
KW - photoactivated
KW - surface engineering
UR - http://www.scopus.com/inward/record.url?scp=85194259956&partnerID=8YFLogxK
U2 - 10.1021/acsaelm.4c00444
DO - 10.1021/acsaelm.4c00444
M3 - Article
AN - SCOPUS:85194259956
SN - 2637-6113
VL - 6
SP - 4356
EP - 4368
JO - ACS Applied Electronic Materials
JF - ACS Applied Electronic Materials
IS - 6
ER -