General Considerations for Improving Photovoltage in Metal-Insulator-Semiconductor Photoanodes

General Considerations for Improving Photovoltage in Metal-Insulator-Semiconductor Photoanodes

Digdaya, I.A. (TU Delft ChemE/Materials for Energy Conversion and Storage)
Trzesniewski, B.J. (TU Delft ChemE/Materials for Energy Conversion and Storage)
Adhyaksa, Gede W.P. (AMOLF)
Garnett, E.C. (AMOLF)
Smith, W.A. (TU Delft ChemE/Materials for Energy Conversion and Storage)

2018

Metal-insulator-semiconductor (MIS) photoelectrodes offer a simple alternative to the traditional semiconductor-liquid junction and the conventional p-n junction electrode. Highly efficient MIS photoanodes require interfacial surface passivating oxides and high workfunction metals to produce a high photovoltage. Herein, we investigate and analyze the effect of interfacial oxides and metal workfunctions on the barrier height and the photovoltage of a c-Si photoanode. We use two metal components in a bimetal contact configuration and observe the modulation of the effective barrier height and the resulting photovoltage as a function of the secondary outer metal. The photovoltage shows a strong linear dependence by increasing the inner metal workfunction, with the highest photovoltage achieved by a MIS photoanode using a platinum inner metal. We also found that coupling a thin aluminium oxide with an interfacial silicon oxide and controlling the oxide thickness can significantly improve the photovoltage of an MIS junction photoanode.

http://resolver.tudelft.nl/uuid:72a8dfac-163b-4618-ad90-65c29a96a1e2

https://doi.org/10.1021/acs.jpcc.7b11747

1932-7447

The Journal of Physical Chemistry C, 122 (10), 5462-5471

Institutional Repository

journal article

© 2018 I.A. Digdaya, B.J. Trzesniewski, Gede W.P. Adhyaksa, E.C. Garnett, W.A. Smith