TY - JOUR
T1 - Nitrogen monoxide and soot oxidation in diesel emissions with platinum–tungsten/titanium dioxide catalysts
T2 - Tungsten loading effect
AU - Oh, Duck Kyu
AU - Lee, Young Jae
AU - Lee, Kwan Young
AU - Park, Jong Soo
N1 - Funding Information:
Funding: This research was funded by the CEFV (Center for Environmentally Friendly Vehicle) as Global-Top Project of KMOE (Ministry of Environment, Korea).
Funding Information:
Acknowledgments: This research was supported by the CEFV (Center for Environmentally Friendly Vehicle) as Global-Top Project of KMOE (Ministry of Environment, Korea).
Publisher Copyright:
© 2020 by the authors. Licensee MDPI, Basel, Switzerland.
PY - 2020/11
Y1 - 2020/11
N2 - Compared with Pt/TiO2, tungsten-loaded Pt–W/TiO2 catalysts exhibit improved activity for NO and soot oxidation. Using catalysts prepared by an incipient wetness method, the tungsten loading effect was investigated using Brunauer–Emmett–Teller surface areas, X-ray diffraction, transmission electron microscopy (TEM), CO pulse chemisorption, H2 temperature-programmed reduction, NH3 temperature-programmed desorption (NH3-TPD), and pyridine Fourier transform infrared (FT-IR) spectroscopy. Loading tungsten on the Pt/TiO2 catalyst reduced the platinum particle size, as revealed in TEM images. CO pulse chemisorption showed that platinum was covered with tungsten and the dispersion of platinum decreased when 5 wt.% or more of tungsten was loaded. The NH3-TPD and pyridine-FT-IR results demonstrated that the number of strong acid sites and Brønsted acid sites in the catalyst were increased by the presence of tungsten. Therefore, a catalyst containing an appropriate amount of tungsten increased the dispersion of platinum, thereby increasing the number of active sites for NO and soot oxidation, and increased the acidity of the catalyst, thereby increasing the activity of soot oxidation by NO2 .
AB - Compared with Pt/TiO2, tungsten-loaded Pt–W/TiO2 catalysts exhibit improved activity for NO and soot oxidation. Using catalysts prepared by an incipient wetness method, the tungsten loading effect was investigated using Brunauer–Emmett–Teller surface areas, X-ray diffraction, transmission electron microscopy (TEM), CO pulse chemisorption, H2 temperature-programmed reduction, NH3 temperature-programmed desorption (NH3-TPD), and pyridine Fourier transform infrared (FT-IR) spectroscopy. Loading tungsten on the Pt/TiO2 catalyst reduced the platinum particle size, as revealed in TEM images. CO pulse chemisorption showed that platinum was covered with tungsten and the dispersion of platinum decreased when 5 wt.% or more of tungsten was loaded. The NH3-TPD and pyridine-FT-IR results demonstrated that the number of strong acid sites and Brønsted acid sites in the catalyst were increased by the presence of tungsten. Therefore, a catalyst containing an appropriate amount of tungsten increased the dispersion of platinum, thereby increasing the number of active sites for NO and soot oxidation, and increased the acidity of the catalyst, thereby increasing the activity of soot oxidation by NO2 .
KW - Exhaust gas after-treatment
KW - Oxidation catalyst
KW - Particulate matter (PM)
KW - Platinum catalyst
KW - Pt/tio
KW - Soot
UR - http://www.scopus.com/inward/record.url?scp=85095763224&partnerID=8YFLogxK
U2 - 10.3390/catal10111283
DO - 10.3390/catal10111283
M3 - Article
AN - SCOPUS:85095763224
SN - 2073-4344
VL - 10
SP - 1
EP - 15
JO - Catalysts
JF - Catalysts
IS - 11
M1 - 1283
ER -