TY - JOUR
T1 - Ultrastable bimetallic catalyst with tuned surface electronic properties for highly selective oxidation of cyclohexane
AU - Wu, Pingping
AU - Cao, Yunxiang
AU - Wang, Yue
AU - Xing, Wei
AU - Zhong, Ziyi
AU - Bai, Peng
AU - Yan, Zifeng
N1 - Publisher Copyright:
© 2018 Elsevier B.V.
PY - 2018/11/1
Y1 - 2018/11/1
N2 - Well-dispersed Au-Pt (2–5 nm) and Au-Pd (1–5 nm) nanoparticles (NPs) supported on mesoporous silica (meso-SiO 2 ) were prepared by a facile one-pot synthesis method using 3-mercapto(propyl)trimethoxysilane (MPTMS) to anchor metal NPs to the support. The obtained catalysts were characterized and evaluated in cyclohexane oxidation with molecular oxygen. The bimetallic NPs catalysts prepared in this work exhibited a high stability with enhanced dispersion because of the intercalation of the metal alloy NPs in the meso-SiO 2 channels via the anchoring effect of MPTMS. The generation of surface Au δ− species in Au-Pt and Au-Pd catalysts was identified due to the alloying of Au with Pt and Pd. Although the electronic modification of Au atoms weakened the capability of Au for O 2 activation and leads to lower cyclohexane conversions on bimetallic catalysts, the deep oxidation reactions were reduced and a higher selectivity of desired products, K/A oil (cyclohexanol and cyclohexanone) was achieved. This work demonstrates an effective preparation method to improve the stability and surface chemical modification of Au NP catalysts, which provides general implications for other noble metal NPs catalysts.
AB - Well-dispersed Au-Pt (2–5 nm) and Au-Pd (1–5 nm) nanoparticles (NPs) supported on mesoporous silica (meso-SiO 2 ) were prepared by a facile one-pot synthesis method using 3-mercapto(propyl)trimethoxysilane (MPTMS) to anchor metal NPs to the support. The obtained catalysts were characterized and evaluated in cyclohexane oxidation with molecular oxygen. The bimetallic NPs catalysts prepared in this work exhibited a high stability with enhanced dispersion because of the intercalation of the metal alloy NPs in the meso-SiO 2 channels via the anchoring effect of MPTMS. The generation of surface Au δ− species in Au-Pt and Au-Pd catalysts was identified due to the alloying of Au with Pt and Pd. Although the electronic modification of Au atoms weakened the capability of Au for O 2 activation and leads to lower cyclohexane conversions on bimetallic catalysts, the deep oxidation reactions were reduced and a higher selectivity of desired products, K/A oil (cyclohexanol and cyclohexanone) was achieved. This work demonstrates an effective preparation method to improve the stability and surface chemical modification of Au NP catalysts, which provides general implications for other noble metal NPs catalysts.
KW - Bimetallic catalyst
KW - Cyclohexane oxidation
KW - Noble metal nanoparticle
KW - Surface electronic modification
UR - http://www.scopus.com/inward/record.url?scp=85049838951&partnerID=8YFLogxK
U2 - 10.1016/j.apsusc.2018.06.300
DO - 10.1016/j.apsusc.2018.06.300
M3 - 文章
AN - SCOPUS:85049838951
SN - 0169-4332
VL - 457
SP - 580
EP - 590
JO - Applied Surface Science
JF - Applied Surface Science
ER -