II-VI族量子点单体的形成、成核及生长机制的理论研究

MX（M = Zn和Cd，X = S、Se和Te）半导体量子点在能源、生物、医学等领域有重大应用，但对其单体形成、成核和生长机理的认识仍存在较多局限，制约了高品质量子点的高效制备。本申请项目运用量子化学计算方法，研究MX量子点制备过程涉及的反应机理、生长机制和结构改性等系列问题，具体包括四个方面：（1）研究MX单体形成过程的化学反应机理，揭示反应过程中M源和X源前驱物、添加组分和配体等在反应过程中的作用，为设计新的合成路线和优化反应条件提供理论指导；（2）模拟由单体形成二聚体及更大量子点的过程，揭示幻数量子点和普通量子点之间不同的成核和生长机制和相互转化条件，为调控量子点大小及其分布提供理论依据；(3)研究典型MX量子点的结构、大小等和光学性质，提出其构效关系和结构优化设计方案；（4）研究核壳型量子点和有机染料改性的量子点的结构本质，从理论上探索利用化学修饰提升量子点性能的途径。

Semiconductor MX (M = Zn or Cd, X = S, Se or Te) quantum dots (QDs) have seen wide applications in many fields such as energy, biology, and medicne. Lack of knowledge in MX monomer formation, nucleation and growth, however, has stalled advancements in the effecient preparation of high-quality QDs. In this project, we will study the reaction mechanism, growth patterns, and structure modifications of MX QDs during their preparation, which contains the following four parts: (1) Study the chemical reaction mechanism of MX monomer formation, providing theoretical guidance for the design of new synthetic strategies and for the modification of reaction conditions. (2) Study the formation details of MX dimer and larger-size QDs, revealing the different nucleation and growth patterns of magic-sized and regular-sized QDs, with the purpose of size distribution control. (3) Study the structure- and size-dependent optical properties of the MX QDs, aiming to establish their structure-property relationship for QD design. (4) Study the structural motif of binary and ternary core-shell, and organic hybrid MX QDs, exploring theoretically the ways of promoting QD performance through chemical modification.