Polaronic transport in Ag-based quaternary chalcogenides

Abstract

Low temperature resistivity measurements on dense polycrystalline quaternary chalcogenides Ag 2þx Zn 1-x SnSe 4 , with x ¼ 0, 0.1, and 0.3, indicate polaronic type transport which we analyze employing a two-component Holstein model based on itinerant and localized polaron contributions. Electronic structure property calculations via density functional theory simulations on Ag 2 ZnSnSe 4 for both energetically similar kesterite and stannite structure types were also performed in order to compare our results to those of the compositionally similar but well known Cu 2 ZnSnSe 4. This theoretical comparison is crucial in understanding the bonding that results in polaronic type transport for Ag 2 ZnSnSe 4 , as well as the structural and electronic properties of both crystal structure types. In addition to possessing this unique electronic transport, the thermal conductivity of Ag 2 ZnSnSe 4 is low and decreases with increasing silver content. This work reveals unique structure-property relationships in materials that continue to be of interest for thermoelectric and photovoltaic applications.

Synthesis, Crystal Structure, and Physical Properties of BaSnS2

“…[12][13][14][15][16] For certain materials, the electrical properties can be modified by a variation in stoichiometry, [17][18][19] while others display transport properties that are atypical of compositions in this class of materials. [20,21] Wide bandgap semiconductor chalcogenides continue to be of interest due to their interest in a broad range of technological applications. [22] Certain compositions have also been synthesized in the nanocrystalline form to investigate the effects of nano-structuring on the transport properties.…”

Thermoelectric Properties of Low Te Concentration‐Doped Cu2ZnSnSe4‐Based Quaternary Alloys

“…[ 36 ] Except for the experimental method, the theoretical calculation is also a good way to confirm the crystal structure of CZTSe. Following the reported calculation work, the little lower formation energy of kesterite structure has been found comparing with stannite structure, [ 37 ] In addition, the formation enthalpy of kesterite phase is −312.7 kJ mol −1 , which is smaller than that of stannite phase (−311.3 kJ mol −1 ) for CZTSe. [ 38 ] Therefore, the kesterite structure is more stable than the stannite structure, and then this kesterite structure is mostly used by researchers to assess the phase structure of synthesized sample.…”

Thermal Properties of the Quaternary Chalcogenide BaCdSnSe4

“…For certain quaternary chalcogenides, a low thermal conductivity can be related to their bonding and crystal structures. [ 10–16 ]…”

“…For certain quaternary chalcogenides, a low thermal conductivity can be related to their bonding and crystal structures. [10][11][12][13][14][15][16] Wide-bandgap quaternary chalcogenides continue to be of interest for frequency conversion in mid-to far-infrared laser applications. [4] One aspect of the bonding and structural arrangement in these materials is the coordination preferences of the metals with the chalcogen, with threefold, fourfold, and sometimes fivefold coordination in the crystal structure.…”