Volume 8, 2017
|Number of page(s)||6|
|Section||Organic Materials and Devices|
|Published online||13 March 2017|
In-situ evaluation of dye adsorption on TiO2 using QCM
1 KTH Royal Institute of Technology, Dept. of Chemistry, Division of Surface and Corrosion Science, 100 44 Stockholm, Sweden
2 KTH Royal Institute of Technology, Material Physics, ICT, 164 40 Stockholm, Sweden
3 Institute for Advanced Studies, IMDEA Nanociencia, c/o Faraday 9, Campus Cantoblanco, 28049 Madrid, Spain
4 Uppsala University, Dept. of Chemistry, Physical Chemistry, Box 523, 751 20 Uppsala, Sweden
5 KTH Royal Institute of Technology, Dept. of Chemistry, Fiber and Polymer Technology, 10044 Stockholm, Sweden
Received: 4 October 2016
Accepted: 24 January 2017
Published online: 13 March 2017
We measured the adsorption characteristics of two organic dyes; triphenylamine-cyanoacrylic acid (TPA-C) and phenoxazine (MP13), on TiO2, directly in a solution based on quartz crystal microbalance (QCM). Monitoring the adsorbed amount as a function of dye concentration and during rinsing allows determination of the equilibrium constant and distinction between chemisorbed and physisorbed dye. The measured equilibrium constants are 0.8 mM-1 for TPA-C and 2.4 mM-1 for MP13. X-ray photoelectron spectroscopy was used to compare dried chemisorbed layers of TPA-C prepared in solution with TPA-C layers prepared via vacuum sublimation; the two preparation methods render similar spectra except a small contribution of water residues (OH) on the solution prepared samples. Quantitative Nanomechanical Mapping Atomic Force Microscopy (QNM-AFM) shows that physisorbed TPA-C layers are easily removed by scanning the tip across the surface. Although not obvious in height images, adhesion images clearly demonstrate removal of the dye.
© Z. Besharat et al., published by EDP Sciences, 2017
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.