UC Berkeley

Zn ₂ SbN ₃ is the first Sb-based crystalline nitride and a photoactive semiconductor.

Ternary nitride semiconductors with wurtzite-derived crystal structures are an emerging class of materials for optoelectronic applications compatible with GaN and related III–V compounds. In particular, II–IV–V ₂ materials such as ZnSnN ₂ and ZnGeN ₂ have been very actively studied for applications in photovoltaics and light emitting devices. However, many other possible wurtzite-derived ternary nitrides have not been reported, and hence their optical and electrical properties remain unknown. Here, we report on Zn ₂ SbN ₃ – the first Sb-based nitride and a photoactive semiconductor. Surprisingly, Zn ₂ SbN ₃ contains Sb in the highest (5+) oxidation state, and in the unusual tetrahedral coordination. This new Zn ₂ SbN ₃ material has a solar-matched 1.6–1.7 eV band gap and shows near-band-edge room-temperature photoluminescence, demonstrating its promise as an optoelectronic semiconductor. Finally, Zn ₂ SbN ₃ can be synthesized at low temperature under a wide range of processing conditions, despite being metastable according to theoretical calculations. All these results, as well as the band position measurements, indicate that Zn ₂ SbN ₃ is a promising emerging semiconductor for applications as an absorber in photovoltaic- and photoelectrochemical solar cells.