Zhang Zongbo, Wang Dan, Xiao Fengyan, Liang Qianying, Luo Yongming, Xu Caihong
Research/Education Centre for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences Beijing 100190 China
School of Chemistry and Chemical Engineering, University of Chinese Academy of Sciences 100049 China.
RSC Adv. 2018 May 8;8(30):16746-16752. doi: 10.1039/c8ra02289e. eCollection 2018 May 3.
SiO/TiO composite coatings are of great interest due to their optical, photocatalytic, electrical and mechanical properties. There are many methods for preparing SiO/TiO composite coatings. Among these, the sol-gel process is eco-friendly and easily implementable for industrial applications. However, it is still a great challenge to prepare dense, uniform and smooth SiO/TiO composite coatings with a sol-gel process. In this work, we show a modified sol-gel process for achieving dense, uniform and smooth SiO/TiO coatings with tetra--butyl titanate modified perhydropolysilazane (PHPS) as a single precursor source, in which PHPS acts as the source for SiO instead of a traditional alkoxylsilane compound. The micro-morphology and composition evolution during the preparation process have been investigated; a smooth surface with a roughness average ( ) below 4.5 nm and a uniform distribution of Ti elements over the entire coating are shown. These dense, uniform SiO/TiO coatings exhibit excellent mechanical robustness, with hardness values as high as 9.45 GPa, excellent optical transparency and hydrophilic properties.
SiO/TiO复合涂层因其光学、光催化、电学和机械性能而备受关注。制备SiO/TiO复合涂层有多种方法。其中，溶胶-凝胶法环保且易于在工业应用中实施。然而，用溶胶-凝胶法制备致密、均匀且光滑的SiO/TiO复合涂层仍然是一个巨大的挑战。在这项工作中，我们展示了一种改进的溶胶-凝胶法，以钛酸四丁酯改性的全氢聚硅氮烷（PHPS）作为单一前驱体源来制备致密、均匀且光滑的SiO/TiO涂层，其中PHPS作为SiO的源，而非传统的烷氧基硅烷化合物。研究了制备过程中的微观形貌和成分演变；结果表明涂层表面光滑，平均粗糙度（ ）低于4.5 nm，并且Ti元素在整个涂层中分布均匀。这些致密、均匀的SiO/TiO涂层表现出优异的机械强度，硬度值高达9.45 GPa，具有出色的光学透明度和亲水性能。
