Record Details
Structural and electronic modification of photovoltaic SnS by alloying
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | Structural and electronic modification of photovoltaic SnS by alloying |
| Names |
Vidal, Julien
(creator) Lany, Stephan (creator) Francis, Jason (creator) Kokenyesi, Robert (creator) Tate, Janet (creator) |
| Date Issued | 2014-03-19 (iso8601) |
| Note | To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by the American Institute of Physics Publishing and can be found at: http://scitation.aip.org/content/aip/journal/jap. |
| Abstract | Emergence of a terawatt scalable photovoltaic (PV) thin film technology is currently impeded by the limited supply of relatively rare elements like In or Te, which has spurred active research in recent years on earth-abundant PV materials. Instead of searching for alternative PV materials, we approach the problem here by structural modification through alloying of a known PV material, namely, tin sulfide. Although SnS is a strong visible light absorber that is naturally p-doped, its indirect band gap reduces the open circuit voltage of SnS-based solar cells. The anisotropic crystal structure results in undesirable anisotropic transport properties. Based on the observation that the isoelectronic sulfides MgS, CaS, and SrS assume the rock-salt structure, we use ab initio calculations to explore the structure and electronic properties of metastable Sn[subscript 1-x](II)[subscript x]S (II=Mg, Ca, Sr) alloys, finding that the isotropic rock-salt phase is stabilized above x=0.2–0.3, and predicting direct band gaps in the range of interest for PV applications, i.e., 0.6–1.5 eV for Ca and Sr alloying. We subsequently synthesized such Sn[subscript 1-x](Ca)[subscript x]S films by pulsed laser deposition, confirmed the cubic rock-salt structure, and observed optical band gaps between 1.1 and 1.3 eV. These results highlight the potential of structural modification by alloying as a route to widen the otherwise limited materials base for promising earth-abundant materials. |
| Genre | Article |
| Identifier | Vidal, J., Lany, S., Francis, J., Kokenyesi, R., & Tate, J. (2014). Structural and electronic modification of photovoltaic SnS by alloying. Journal of Applied Physics, 115(11), 113507. doi:10.1063/1.4868974 |
