纳米材料具有大的比表面积，是决定材料光电特性的主要因素，也直接影响纳米材料的实际应用。对一些纳米结构而言，当水分子接近表面原子大约纳米量级的距离时，水分子会在纳米颗粒的自催化作用下发生水的裂解反应，在颗粒表面形成?H和?OH键合结构，有效地降低了表面水裂解的活性势垒，为氢/氧气的制备提供了新的机理。本项目集中在有前期良好工作基础的四种半导体纳米结构SiC、In2O3、ZnO和SnO2的表面取向生长和对水分子的裂解效应上，在制备尺寸均匀、晶面可控的纳米颗粒的前提下，通过对表面结构的表征和功能化设计，从原子/分子的层次上，探索表面原子结构同水分子相互作用的物理机制，特别是理解表面原子对水分子的自裂解反应机理，在此基础上，弄清纳米颗粒表面和水分子相互作用的电化学和光电化学过程的物理本质，为提高氢气和氧气的产生效率，找到合适的方法和途径，最终为清洁能源的产生提供理论基础和一些材料上的保证。

Nanostructured material is of large specific surface which is a main factor determining optical and electric properties and directly affecting their practical applications. For some nanostructures, when water molecules approach the surafce atoms at about nanometer distance, the water molecules will take place splitting reaction under self-catalysis to form -H and -OH bonding structures at the nanocrystal surface, which will effectively lower the activation barrier of nanocrystal surface. This is a new mechanism for hydrogen/oxygen evolution. The current project focuses on the orientation growth and water splitting effect of the surfaces of four kinds of semiconductor nanostructures, SiC, In2O3、ZnO, and SnO2, which have partially been investigated previously. By fabricating controllable nanocrystals with uniform sizes and identical crystal facets, we will explore physical mechanisms of the interaction between the surface atomic structure and water molecules from atomic/moleculous size levels and by specially designing and characterizing the surface structures, we will seek self-splitting mechanism of the surface atoms on water molecules. Based on these studies above, we expect to clarify the physical essence of electrochemical and opto-electrochemical processes and then find suitable ways to improve the hydrogen and oxygen evolution. Our final goal is to provide the theoretical basis and some useful materials for the production of new clean energy source.