p-型/n-型双组分表面自组装层的结构调控及其界面电学性质研究,对理解自组装领域中的基本科学问题有重要意义，也与分子及有机电子学的发展密切相关。目前，对小分子体系的研究取得了丰富的结果，但对聚合物体系研究较少。我们选择了（缺电子杂环-噻吩）共聚的p-型高分子，利用缺电子杂环有序地调节聚合物的能级位置；选择HOMO接近、LUMO位置不同的两类n-型小分子，但只有一类n-型小分子可以形成氢键。据此，有规律地调节p-n分子间的能级匹配与作用力。我们将：1）利用溶剂性质、高温退火等调控组装结构；2）通过扫描隧道显微镜、理论计算与模拟等表征组装结构，揭示p-n分子间的堆积方式；理解分子间作用力对组装结构的形成、演化及最终热力学稳定组装结构的影响；3）利用光电子能谱、扫描隧道谱、理论计算等考察p-n分子界面上的能级排布、电子隧穿等电学性质，并分析界面电学性质与p-n分子间堆积方式、能级匹配的关系。

Tuning the surface assemblies of p-type/n-type bicomponent systems and exploring the electronic properties at p-n molecular interfaces play significant roles in varied fundamental researches of surface assembly such as understanding the nature of assorted noncovalent interactions and their fine balances, disclosing the assembling behaviors and principles in complex and life environments, as well as sorts of applications including assembly functionalization, molecular and organic electronics development. Currently most of researches were carried out in high vacuum, therefore both p-type and n-type compounds are limited to small molecules. Semiconductor polymers are very few involved in these studies although they are as important as small molecules to the development of molecular and organic electronics. In this project, surface assemblies of p-type poly(electron-deficient heterocyclic unit-thiophene) compounds/n-type small molecules will be investigated in detail. The p-type polymers and n-type small molecules in this project are designed with great care. Different electron-deficient units are used to tune the orbital positions of p-type polymers gradually. We choose two kinds of n-type small molecules whose highest occupied molecular orbital (HOMO) positions are close to each other but their lowest unoccupied molecular orbital (LUMO) positions are different. Thus, in our systems, the matching of orbital levels between p-type and n-type component will be adjusted systematically. Furthermore, only one kind of n-type molecule can possibly forms hydrogen bond with p-type polymers, indicating that the interactions of p-type polymers with two kinds of n-type compounds differ very much. Thus, in this project, we will 1) systematically tune the assembling structures of p-type polymer/n-type small molecule bicomponent systems through adjusting the properties of solvents and annealing parameters; 2) reveal the assembling structures and stacking fashions of p-n molecules with scanning tunneling microscopy, theoretical calculation and simulations; understand the effect of the noncovalent interactions between p-type and n-type molecules on the formation and transformation of surface assemblies and the features of thermodynamic favorable structures; 3) characterize the electronic properties at p-n molecular interfaces including energy level alignment, tunneling process etc. through X-ray/ultraviolet photoelectron spectroscopy, scanning tunneling spectroscopy and theoretical calculations etc.; and analyze the influence of orbital matching and stacking styles of p-n molecules on its interface electronic properties. The results will provide fundamental supports for rational tuning and fabrication of bicomponent surface assemblies, and for developing molecular/organic electronics in a fast yet low cost solution method in future.