Research Project
Grant-in-Aid for Challenging Exploratory Research
In order to understand the intrinsic state of solid surfaces via liquid contact angle measurement by excluding the extrinsic effects such as surface contamination, a high-vacuum contact angle measurement system connected to a sample preparation chamber was developed. The contact angle of non-volatile ionic liquids (ILs) on TiO2 single crystal surfaces and organic thin films prepared in vacuum was evaluated without air exposure. Our findings can be summarized as follows: (1) airborne contaminations change the ILs contact angle significantly; (2) the interaction between IL and TiO2 depends on hydrophilic/hydrophobic nature of ILs; (3) the coverage and number of molecular layers of an organic thin film can be estimated by the IL contact angle. These results suggest that a simple contact angle measurement in vacuum using ILs as probe fluids would allow us to investigate the intrinsic surface state of solids.
All 2016 2015
All Journal Article (2 results) (of which Peer Reviewed: 2 results, Acknowledgement Compliant: 2 results)
CrystEngComm
Volume: 18 Issue: 19 Pages: 2299-3403
10.1039/c6ce00620e
J. Phys. Chem. C.
Volume: 119 Issue: 31 Pages: 17755-17761
10.1021/acs.jpcc.5b05276
