Documents

DOI

  • Ibadillah A. Digdaya
  • Bartek J. Trześniewski
  • Gede W.P. Adhyaksa
  • E.C. Garnett
  • Wilson A. Smith

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.

Original languageEnglish
Pages (from-to)5462-5471
JournalJournal of Physical Chemistry C
Volume122
Issue number10
DOIs
Publication statusPublished - 2018

ID: 45050837