Anisotropic Surface Modification of Metal Oxide Nanoparticles

Abstract

This research aims to develop a method to realize anisotropic surface modification of metal oxide nanoparticles. The anisotropic surface modification can be realized under the condition that the interaction with organic molecules largely depends on the crystal faces. In order to evaluate the interaction between organic molecules and crystal faces of metal oxide nanoparticles, we placed rutile and anatase phases of TiO₂ single crystal substrate in high-temperature and high-pressure water with various organic molecules. After this hydrothermal treatment, substrates were rinsed and analyzed by contact angle measurement and X-ray photoelectron spectroscopy. The results showed that rutile (110) face had higher affinity with phosphoric acid and anatase (101) also had higher affinity with amines. These results are indispensable to realize anisotropic surface modification of metal oxide nanoparticles during their synthesis.