2017 Fiscal Year Research-status Report
Photo-electrochemical water-splitting on conducting polymer composite materials
| Project/Area Number |
16K05922
|
|---|
| Research Institution | Waseda University |
|---|
Principal Investigator |
ウィンザージェンセン B 早稲田大学, 理工学術院, 教授(任期付) (70770410)
|
|---|
| Project Period (FY) |
2016-04-01 – 2019-03-31
|
| Keywords | Water splitting / Conducting polymers / Hydrogen / Electrochemistry |
|---|
| Outline of Annual Research Achievements |
I2 has successfully been identified as ideal replacement oxidant for polyterthiophene polymerization with resulting H2 evolution. The catalytic activity for the I2-PTTh is not following the expected Nernstian dependency of pH, but rather shows an increase in onset potential when moving to higher pH, which make I2-PTTh an ideal match for oxygen evolution electrodes like MnOx. Thus overall water-splitting could be obtained at only 0.3V bias potential.A range of terthiophene derivatives was synthesized with the perspective to lower the HOMO level in order to further increase the onset potential for the H2 evolution. These novel polymers all show similar pH dependency. Thus far, poly, polymerized with I2 as oxidant, was found to be the best candidate with H2 evolution at a photo-voltage.
|
| Current Status of Research Progress |
Current Status of Research Progress
2: Research has progressed on the whole more than it was originally planned.
Reason
The work related to I2 as oxidant for the polymerization of ter-thiophene derivatives has efficiently focused the research activities to a much narrower range of possible derivatives by providing an “universal” metal-free polymerization platform for the “ter-mer” motive. The incorporation of more hydrophilic groups in the polymers has not resulted in improved performance for the H2 evolution, suggesting that the hydrophobic character of the polymers is not limiting the performance, rather optimization of morphology has been identified crucial for the H2 evolution.
|
| Strategy for Future Research Activity |
The 3rd year will mainly concern the performance of PTTh derivatives with tuned HOMO levels, where the microscopic and macroscopic morphology is optimized. The focus will here be twofold in order to increase the polymer/water interphase area: 1) Selecting, and testing conducting 3D substrates to increase the macroscopic surface area, 2) optimizing the pre-polymerization (microscopic) morphology of the (ter-)monomer coatings, which is maintained during the polymerization process using I2 vapour.
A particular task will be to decrease the resistance of the electrode substrate as well as the photo-active polymer, partly by material selection for the substrate, partly by optimizing the thickness of the polymer layer. Ultimately a gas-permeable electrode will be pursued to allow separation of H2 through the porous material.
There are not intended any strategical changes of the research plans for the and 3rd year of the project.
|
Research Products
(3 results)
