当前位置: X-MOL 学术Nano Lett. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Quantitative Analysis of Different Formation Modes of Platinum Nanocrystals Controlled by Ligand Chemistry
Nano Letters ( IF 9.6 ) Pub Date : 2017-09-11 00:00:00 , DOI: 10.1021/acs.nanolett.7b02751
Xi Yin 1 , Miao Shi 1 , Jianbo Wu 1 , Yung-Tin Pan 1 , Danielle L. Gray 2 , Jeffery A. Bertke 2 , Hong Yang 1
Affiliation  

Well-defined metal nanocrystals play important roles in various fields, such as catalysis, medicine, and nanotechnology. They are often synthesized through kinetically controlled process in colloidal systems that contain metal precursors and surfactant molecules. The chemical functionality of surfactants as coordinating ligands to metal ions however remains a largely unsolved problem in this process. Understanding the metal–ligand complexation and its effect on formation kinetics at the molecular level is challenging but essential to the synthesis design of colloidal nanocrystals. Herein we report that spontaneous ligand replacement and anion exchange control the form of coordinated Pt–ligand intermediates in the system of platinum acetylacetonate [Pt(acac)2], primary aliphatic amine, and carboxylic acid ligands. The formed intermediates govern the formation mode of Pt nanocrystals, leading to either a pseudo two-step or a one-step mechanism by switching on or off an autocatalytic surface growth. This finding shows the importance of metal–ligand complexation at the prenucleation stage and represents a critical step forward for the designed synthesis of nanocrystal-based materials.

中文翻译:

配体化学控制的铂纳米晶体不同形成方式的定量分析

定义明确的金属纳米晶体在催化,医学和纳米技术等各个领域中发挥着重要作用。它们通常是在包含金属前体和表面活性剂分子的胶体系统中通过动力学控制的过程合成的。然而,表面活性剂作为金属离子配位配体的化学官能度在此过程中仍然是一个主要未解决的问题。在分子水平上了解金属-配体的络合及其对形成动力学的影响是具有挑战性的,但对于胶体纳米晶体的合成设计至关重要。在这里我们报道自发的配体置换和阴离子交换控制了乙酰丙酮铂[Pt(acac)2],脂族伯胺和羧酸配体。形成的中间体控制Pt纳米晶体的形成模式,通过打开或关闭自催化表面生长来导致伪两步或一步机理。这一发现表明了金属-配体络合在预成核阶段的重要性,并代表了设计合成纳米晶体基材料的关键一步。
更新日期:2017-09-12
down
wechat
bug