Synergetic Catalysis of Non-noble Bimetallic Cu鈥揅o Nanoparticles Embedded in SiO2 Nanospheres in Hydrolytic Dehydrogenation of Ammonia Borane

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• 作者：Qilu Yao ; Zhang-Hui Lu ; Yuqing Wang ; Xiangshu Chen ; Gang Feng
• 刊名：Journal of Physical Chemistry C
• 出版年：2015
• 出版时间：June 25, 2015
• 年：2015
• 卷：119
• 期：25
• 页码：14167-14174
• 全文大小：482K
• ISSN：1932-7455

文摘

Ultrafine non-noble bimetallic Cu鈥揅o nanoparticles (鈭? nm) encapsulated within SiO₂ nanospheres (Cu鈥揅o@SiO₂) have been successfully synthesized via a one-pot synthetic route in a reverse micelle system and characterized by SEM, TEM, EDS, XPS, PXRD, ICP, and N₂ adsorption鈥揹esorption methods. In each core鈥搒hell Cu鈥揅o@SiO₂ nanosphere, several Cu鈥揅o NPs are separately embedded in SiO₂. Compared with their monometallic counterparts, the bimetallic core鈥搒hell nanospheres Cu_xCo_1鈥?i>x@SiO₂ with different metal compositions show a higher catalytic performance for hydrogen generation from the hydrolysis of ammonia borane (NH₃BH₃, AB) at room temperature, due to the strain and ligand effects on the modification of the surface electronic structure and chemical properties of Cu鈥揅o NPs in the SiO₂ nanospheres. Especially, the Cu_0.5Co_0.5@SiO₂ nanospheres show the best catalytic performance among all the synthesized Cu_xCo_1鈥?i>x@SiO₂ catalysts in the hydrolytic dehydrogenation of AB. In addition, the activation energy (E_a) of Cu_0.5Co_0.5@SiO₂ core鈥搒hell structured nanospheres for the hydrolysis of AB is estimated to be 24 卤 2 kJ mol^鈥?, relatively low values among the bimetallic catalysts reported for the same reaction. Furthermore, the multi-recycle test shows that the bimetallic Cu_0.5Co_0.5@SiO₂ core鈥搒hell nanospheres are still highly active for hydrolytic dehydrogenation of AB even after 10 runs, implying a good recycling stability in the catalytic reaction.