Giant bulk photovoltaic effect in solar cell architectures with ultra-wide bandgap Ga2O3 transparent conducting electrodes. (December 2019)

• Record Type: Journal Article
• Authors: Pérez-Tomás, A.; Chikoidze, E.; Dumont, Y.; Jennings, M.R.; Russell, S.O.; Vales-Castro, P.; Catalan, G.; Lira-Cantú, M.; Ton –That, C.; Teherani, F.H.; Sandana, V.E.; Bove, P.; Rogers, D.J.
• Is Part Of: Materials today energy. Volume 14(2019)
• Publication Date: 2019-12
• Subjects: Ultra-wide bandgap semiconductors -- Transparent conducting oxide -- Gallium oxide -- Ga2O3 -- Ferroelectric photovoltaics -- Pb(Zr, Ti)O3 -- Bulk photovoltaic effect -- Solar cell architecture; Energy development -- Periodicals; Energy industries -- Periodicals; Power resources -- Periodicals; Energy policy -- Periodicals; Energy development; Energy industries; Energy policy; Power resources; Electronic journals; Periodicals; 621.042
• DOI: 10.1016/j.mtener.2019.100350
• Languages: English
• ISSNs: 2468-6069

Abstract

Abstract: The use of ultra-wide bandgap transparent conducting beta gallium oxide (β-Ga2 O3 ) thin films as electrodes in ferroelectric solar cells is reported. In a new material structure for energy applications, we report a solar cell structure (a light absorber sandwiched in between two electrodes - one of them - transparent) which is not constrained by the Shockley–Queisser limit for open-circuit voltage ( V oc ) under typical indoor light. The solar blindness of the electrode enables a record-breaking bulk photovoltaic effect (BPE) with white light illumination (general use indoor light). This work opens up the perspective of ferroelectric photovoltaics which are not subject to the Shockley-Queisser limit by bringing into scene solar-blind conducting oxides. Highlights: Here, we use the ultra-wide bandgap semiconductor Ga2 O3 for the first time in a solar cell as a transparent superstrate electrode We show that its ultra-wide bandgap resolves a long-standing problem for ferroelectric photovoltaic devices. The ultra-wide bandgap of Ga2 O3 ( ~ 5 eV) inherently avoids the problem of undesirable photo-carrier injection that afflicts all other currently available transparent conductors. Adoption of the solar blind transparent conductor has resulted in a record-breaking white-light-induced photoelectric field (0.7 MV/cm).