%0 Journal Article
%A Septina, Wilman
%A Prabhakar, Rajiv Ramanujam
%A Wick, René
%A Moehl, Thomas
%A Tilley, S. David
%D 2017
%T Stabilized Solar Hydrogen Production with CuO/CdS
Heterojunction Thin Film Photocathodes
%U https://acs.figshare.com/articles/journal_contribution/Stabilized_Solar_Hydrogen_Production_with_CuO_CdS_Heterojunction_Thin_Film_Photocathodes/4634023
%R 10.1021/acs.chemmater.6b05248.s001
%2 https://acs.figshare.com/ndownloader/files/7544677
%K 0 V RHE
%K band gap
%K champion electrode
%K faradaic efficiency
%K Stabilized Solar Hydrogen Production
%K 1 M phosphate buffer solution
%K photocorrosion
%K material
%K Photoelectrochemical measurements
%K TiO 2 layer
%K energy conversion
%K hydrogen-producing photocurrents
%K n-type CdS buffer layer
%K water splitting
%K Film Photocathodes Cupric oxide
%K CuO
%K hydrogen evolution
%K sulfide surface
%K 0.45 V RHE
%K record photovoltage
%K band alignment
%X Cupric oxide (CuO)
is a promising material for large-scale, economic
solar energy conversion due to the abundance of copper, suitable band
gap, and ease of fabrication. For application as a photocathode for
water splitting, the main challenge is prevention of the inherent
photocorrosion in aqueous media. Photoelectrochemical measurements
of bare CuO thin films prepared by oxidation of electroplated Cu indicated
that the vast majority of the photocurrent in 1 M phosphate buffer
solution (pH 7) comes from photocorrosion of the CuO into metallic
Cu, with a faradaic efficiency for hydrogen evolution of ∼0.01%.
We found that deposition of an n-type CdS buffer layer underneath
a protective TiO2 layer yielded a stable and efficient
photoelectrode, with the champion electrode giving 1.68 mA cm–2 at 0 VRHE and an onset potential of ca.
0.45 VRHE. We attribute a favorable band alignment of CuO/CdS
for the record photovoltage obtained with this material and a high
conformality of the TiO2 layer on the sulfide surface for
the high stability of hydrogen-producing photocurrents (faradaic efficiency
∼100%).
%I ACS Publications