Showcasing the optical properties of monocrystalline zinc phosphide thin films as an earth-abundant photovoltaic absorber. Issue 2 (22nd December 2021)

• Record Type: Journal Article
• Authors: Stutz, Elias Z.; Zamani, Mahdi; Damry, Djamshid A.; Buswell, Léa; Paul, Rajrupa; Escobar Steinvall, Simon; Leran, Jean-Baptiste; Boland, Jessica L.; Dimitrievska, Mirjana; Fontcuberta i Morral, Anna
• Is Part Of: Materials advances. Volume 3:Issue 2(2022)
• Page Start: 1295
• Page End: 1303
• Publication Date: 2021-12-22
• Subjects: 620.11
• DOI: 10.1039/d1ma00922b
• Languages: English
• ISSNs: 2633-5409

Abstract

Abstract : Optoelectronic properties of zinc phosphide (Zn3 P2 ), a promising photovoltaic absorber, are explored using photoluminescence and terahertz-probe spectroscopy. Abstract : Zinc phosphide, Zn3 P2, is a semiconductor with a high absorption coefficient in the spectral range relevant for single junction photovoltaic applications. It is made of elements abundant in the Earth's crust, opening up a pathway for large deployment of solar cell alternatives to the silicon market. Here we provide a thorough study of the optical properties of single crystalline Zn3 P2 thin films grown on (100) InP by molecular beam epitaxy. The films are slightly phosphorus-rich as determined by Rutherford backscattering. We elucidate two main radiative recombination pathways: one transition at approximately 1.52 eV attributed to zone-center band-to-band electronic transitions; and a lower-energy transition observed at 1.3 eV to 1.4 eV attributed to a defect band or band tail related recombination mechanisms. We believe phosphorus interstitials are likely at the origin of this band.