Ordered sphalerite derivative Cu5Sn2S7: a degenerate semiconductor with high carrier mobility in the Cu–Sn–S diagram. Issue 17 (21st April 2021)

• Record Type: Journal Article
• Authors: Pavan Kumar, Ventrapati; Lemoine, Pierric; Carnevali, Virginia; Guélou, Gabin; Lebedev, Oleg I.; Boullay, Philippe; Raveau, Bernard; Al Rahal Al Orabi, Rabih; Fornari, Marco; Prestipino, Carmelo; Menut, Denis; Candolfi, Christophe; Malaman, Bernard; Juraszek, Jean; Guilmeau, Emmanuel
• Is Part Of: Journal of materials chemistry. Volume 9:Issue 17(2021)
• Page Start: 10812
• Page End: 10826
• Publication Date: 2021-04-21
• Subjects: Materials -- Research -- Periodicals; Chemistry, Analytic -- Periodicals; Environmental sciences -- Research -- Periodicals; 543.0284
• DOI: 10.1039/d1ta01615f
• Languages: English
• ISSNs: 2050-7488

Abstract

Abstract : The discovery of the monoclinic Cu5 Sn2 S7 phase adds a high mobility member to the Cu–Sn–S diagram and demonstrates how the crystal structure can be advantageously manipulated to design novel compositions for energy-oriented applications. Abstract : Regardless of the complexity of the phase diagram of the Cu–Sn–S system, several compositions near the prototypical mohite Cu2 SnS3 have arisen as potential non-toxic, earth-abundant and cost-efficient photovoltaic and thermoelectric materials. In this work, we revisited the Cu2+ x Sn1− x S3 system and discovered a monoclinic ( C 2) ordered sphalerite derivative member, Cu5 Sn2 S7 . Using a combination of synchrotron diffraction and spectroscopy, transmission electron microscopy, precession-assisted electron diffraction tomography, Mössbauer spectroscopy, first principles calculations and transport properties measurements, we discuss the structure–thermoelectric properties relationships and clarify the interesting crystal chemistry in this system. The ternary sulfide Cu5 Sn2 S7 exhibits a degenerate semiconducting behavior with exceptionally high hole mobility originating from the interplay between atomic ordering and charge delocalization.