College of Chemistry and Materials Science, The Key Laboratory of Functional Molecular Solids, Ministry of Education, Anhui Laboratory of Molecular-Based Materials, Center for Nano Science and Technology , Anhui Normal University , Wuhu 241000 , China.
Key Laboratory of Applied Surface and Colloid Chemistry, National Ministry of Education, Shaanxi Key Laboratory for Advanced Energy Devices, Shaanxi Engineering Lab for Advanced Energy Technology, School of Materials Science and Engineering , Shaanxi Normal University , Xi'an 710119 , China.
ACS Appl Mater Interfaces. 2018 Sep 5;10(35):29543-29551. doi: 10.1021/acsami.8b08657. Epub 2018 Aug 24.
Synthesis of hollow metal nanocrystals (NCs) is greatly attractive for their high active surface areas, which gives rise to excellent catalytic activity. Taking PdPt alloy nanostructure as an example, we designed a synthetic tactic for the preparation of hollow metal nanostructures by delicate control over the difference in the reduction kinetic of metal precursors. At a high reduction rate difference, the Pd layer forms from HPdCl and is subsequently etched, leading to the formation of a hollow space. A solid PdPt structure is achieved when the reduction rate of Pd and Pt precursor is comparable. Obviously, the hollow space and composition are tunable as well by adjusting the reduction rate difference. More importantly, the prepared hollow PdPt nanostructures exhibit a branched outer, porous wall, and rough hollow interior. The branched outer and rough hollow interior provide the higher density of unsaturated atoms, whereas the porous wall serves as channels connecting the inner, outer, and reactive agents. Moreover, the periodic self-consistent density function theory suggests that the d-band theory density of state of the PdPt nanoalloys is upshifted in comparison to the monometallic component, which will beneficial for improvement in their catalytic performances. Electrocatalytic tests reveal that the PdPt bimetallic NCs, especially for PtPd nanostructures, show excellent catalytic activity and stability toward methanol oxidation reaction owing to their special structures as well as compositions.
中空金属纳米晶体（NCs）的合成因其具有高比表面积而极具吸引力，这使其具有出色的催化活性。以 PdPt 合金纳米结构为例，我们通过精细控制金属前体的还原动力学差异，设计了一种制备中空金属纳米结构的合成策略。在高还原速率差异下，Pd 层从 HPdCl 形成并随后被蚀刻，从而形成中空空间。当 Pd 和 Pt 前体的还原速率相当时，就会形成固体 PdPt 结构。显然，通过调整还原速率差异，中空空间和组成也是可调的。更重要的是，所制备的中空 PdPt 纳米结构具有分支的外部、多孔的壁和粗糙的内部中空。分支的外部和粗糙的内部中空提供了更高密度的不饱和原子，而多孔的壁则作为连接内部、外部和反应物的通道。此外，周期性自洽密度泛函理论表明，与单金属组分相比，PdPt 纳米合金的 d 带理论态密度向上移动，这将有利于提高它们的催化性能。电催化测试表明，PdPt 双金属 NCs，特别是 PtPd 纳米结构，由于其特殊的结构和组成，对甲醇氧化反应表现出优异的催化活性和稳定性。
