Enhanced selective hydrodechlorination of 1,2-dichloroethane to ethylene on Pt-Ag/TiO₂ catalysts prepared by sequential photodeposition

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• 作者：Yuxiang Han ; Juan Zhou ; Wenjuan Wang ; Haiqin Wan ; Zhaoyi Xu ; Shourong Zheng ; Dongqiang Zhu
• 关键词：Catalytic hydrodechlorination ; 1 ; 2-Dichloroethane ; Ethylene selectivity ; Pt&ndash ; Ag/TiO2 catalyst ; Sequential photodeposition
• 刊名：Applied Catalysis B: Environmental
• 出版年：2012
• 出版时间：21 August, 2012
• 年：2012
• 卷：125
• 期：Complete
• 页码：172-179
• 全文大小：1158 K

文摘

TiO₂ supported Pt-Ag bimetallic catalysts were prepared using a sequential photodeposition method (denoted as pd-Pt-Ag/TiO₂). For comparison, supported bimetallic catalysts were also prepared using the conventional impregnation method (denoted as im-Pt-Ag/TiO₂). The catalysts were characterized by X-ray diffraction, transition electron microscopy, CO chemisorption, IR spectroscopy of CO adsorption, and X-ray photoelectron spectroscopy. Characterization results indicated that photodeposition led to site-specific deposition of metallic Ag domain on the surface of Pt particles and thus to the formation of core-shell (Pt@Ag) like bimetallic species, which effectively blocked the adjacent Pt sites. However, Pt-Ag ensemble was predominant in im-Pt-Ag/TiO₂. Accordingly, hydrodechlorination of 1,2-dichloroethane exhibited substantially higher ethylene selectivity and catalytic stability on pd-Pt-Ag/TiO₂ than on im-Pt-Ag/TiO₂ at similar Ag loading levels. Findings from this study highlight the potential of using sequentially photodeposited core-shell like bimetallic catalysts to enhance the ethylene selectivity in hydrodechlorination of 1,2-dichloroethane.