报告题目：On the exploration of the formation of colloidal semiconductor magic-size clusters

报 告 人：余睽 教授 四川大学原子与分子物理研究所

  《ACS Applied Materials and Interfaces 》执行主编

主 持 人：张立军 教授

报告时间：2018年10月25日 10:00

报告地点：南区唐敖庆楼D区429报告厅

主办单位：材料科学与工程学院

摘  要：

Colloidal semiconductor magic-size clusters (MSCs) differ significantly from conventional quantum dots (QDs) in many respects. For example, when samples are extracted from a single reaction batch, MSCs are characterized by a constant and persistent absorption peak position, while the absorption peak position of QDs redshifts due to their growth in size. Furthermore, MSCs exhibit relatively narrow optical bandwidth, compared to corresponding QDs, attributed to relatively uniform size distributions. However, little is known about the structures of the MSCs. Here, I will present our latest advances on a selective two-step approach to various single-ensemble MSCs, which are not complicated by the presence of QDs. In the first step, a pre-nucleation stage sample is obtained, which is transparent in optical absorption. In the second step, MSCs are formed from the first-step sample at relatively low temperatures, such as room temperature, either by incubation or by dispersion in a solvent. Using ZnSe as a model system, I will demonstrate that the formation of MSCs starts with the self-assembly of the cation and anion precursors. Furthermore, I will present the various MSCs obtained from our selective two-step approach, which is obviously different from the conventional hot-injection and heating up approaches. Hopefully, the presentation will facilitate mutual interest on the exploration of the structure-property relationship of MSCs.

个人介绍：

余睽，四川大学教授，四川省创新领军人才，美国化学学会(ACS) Applied Materials and Interfaces 执行主编。高分子物理与化学博士(McGill Univ, Canada)，博士后(McMaster Univ, Canada) 和(Sandia National Laboratories, USA)。在2014年以前，助理--副--高级研究员(National Research Council of Canada) and ISO TC229 和IEC TC113 纳米技术咨询委员会专家委员，主持或共同主持21项加拿大国家级科研项目。2014年起，全职任教四川大学原子与分子物理研究所和国家生物材料工程研究中心。研究领域主要包括：(1) 纳米材料的设计、计算、制备和表征；(2) 水凝胶的设计合成；(3) 功能材料与细胞的相互作用。回四川大学后主持国家重点研发计划《基于材料基因工程诱导的骨和软骨修复材料研制》和国家自然科学基金2项。