11月5日 Prof. J. Belloni 学术报告:Nucleation and Growth of Nanoclusters. Applications.

发布时间:2012-10-31浏览次数:137



报告人:Prof. J. Belloni

报告题目:Nucleation and Growth of Nanoclusters. Applications.

时间:2012年11月5日下午3点-5点

地点:中国科大核科学技术学院16楼会议室(1617-1618)

 

报告人简介: 

Prof. J. Belloni是法国巴黎南大学与法国国家研究中心(CNRS)共建的物理化学实验室前主任。主要从事辐射化学与超快反应动力学研究。发表论文、专著300来篇,并获得包括法国骑士勋章(Chevalier de l’Ordre National du Mérite)等许多褒奖。1996年被授予中国科学技术大学名誉教授。

 

报告摘要: 

The aim of this short review is to describe how the main mechanisms involved in the synthesis of metal and semiconductor nanoclusters via the wet process of the reduction of metal ions were mostly elucidated owing to the methodology of radiation chemistry, in the pulse or the steady state regime. In particular, the key concept on the thermodynamics of properties of clusters differing from the bulky state of matter and depending on the number of atoms they contain was originally evidenced by these methods.The nuclearity-dependent properties of the clusters play a predominant role already during their nucleation and growth, hence on their final shape, size and structure.

Owing to the deep penetration of ionizing radiation and to the homogeneous production of strong reducing species throughout the solution, irradiation has been used as a particularly powerful tool to observe the early and transient steps of ion reduction and metal atom formation, nucleation and growth of atoms into clusters. The understanding of the mechanisms has thus been applied to guide the radiolytic synthesis of mono- and multi-metallic up to controlled and homodisperse structure sizes, in the form of either subcolloidal suspensions or inclusions in various materials. This understanding also explains most of the phenomena occurring during the cluster synthesis via other chemical, photo- or electrochemical routes. When nanoclusters are stabilized in size, their specific properties explain mechanisms in various domains of nanosciences where they play a crucial role, such as optics, catalysis photography, phase transition.