Facile synthesis of Pd concave nanocubes： From kinetics to mechanistic understanding and rationally designed protocol  

作　　者：Madeline Vara Younan Xia 

机构地区：[1]School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA 30132, USA [2]The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA 30132, USA

出　　处：《Nano Research》2018年第6期3122-3131,共10页纳米研究（英文版）

摘　　要：We report a rationally designed one-pot method for the facile synthesis of Pd concave nanocubes in an aqueous solution at room temperature by manipulating the reduction kinetics through the selection of a proper combination of a salt precursor （PdBr4^2-） and reductant （sodium ascorbate）. Our kinetic analysis demonstrates that, through this selection, the nucleation and growth of Pd nanocrystals could be effectively separated into two kinetic regimes involving distinctive reduction pathways： i） solution reduction for the initial formation of single-crystal seeds and ii） surface reduction for the formation of concave nanocrystals via autocatalytic growth from the single-crystal seeds. The suppressed surface diffusion at room temperature, when coupled with the capping effect of bromide ions, ultimately leads to the formation of concave nanocubes with an asymmetric shape and high-index facets, whose synthesis would otherwise require multiple steps and the use of elevated temperatures.We report a rationally designed one-pot method for the facile synthesis of Pd concave nanocubes in an aqueous solution at room temperature by manipulating the reduction kinetics through the selection of a proper combination of a salt precursor （PdBr4^2-） and reductant （sodium ascorbate）. Our kinetic analysis demonstrates that, through this selection, the nucleation and growth of Pd nanocrystals could be effectively separated into two kinetic regimes involving distinctive reduction pathways： i） solution reduction for the initial formation of single-crystal seeds and ii） surface reduction for the formation of concave nanocrystals via autocatalytic growth from the single-crystal seeds. The suppressed surface diffusion at room temperature, when coupled with the capping effect of bromide ions, ultimately leads to the formation of concave nanocubes with an asymmetric shape and high-index facets, whose synthesis would otherwise require multiple steps and the use of elevated temperatures.

关 键 词：PD concave cubes growth kinetics nanocrystal synthesis 

分 类 号：TP333.4[自动化与计算机技术—计算机系统结构] U231.1[自动化与计算机技术—计算机科学与技术]