Synthesis and physical characteristics of narrow bandgap chalcogenide SnZrSe 3

Rokas Kondrotas; Remigijus Juškėnas; Arūnas Krotkus; Vidas Pakštas; Artūras Suchodolskis; Algirdas Mekys; Marius Franckevičius; Martynas Talaikis; Katri Muska; Xiaofeng Li; Marit Kauk-Kuusik; Victor Kravtsov

doi:10.12688/openreseurope.15168.2

Synthesis and physical characteristics of narrow bandgap chalcogenide SnZrSe ₃

Open Res Eur. 2023 May 17:2:138. doi: 10.12688/openreseurope.15168.2. eCollection 2022.

Affiliations

¹ Center for Physical Sciences and Technology, Vilnius, 10257, Lithuania.
² Institute of Photonics and Nanotechnology, Vilnius University, Vilnius, 10257, Lithuania.
³ Department of Materials and Environmental Technology, Tallinn University of Technology, Tallinn, 19086, Estonia.
⁴ Institute of Applied Physics, Chisinau, MD2028, Moldova.

Abstract

Background: The development of organic/inorganic metal halide perovskites has seen unprecedent growth since their first recognition for applications in optoelectronic devices. However, their thermodynamic stability and toxicity remains a challenge considering wide-scale deployment in the future. This spurred an interest in search of perovskite-inspired materials which are expected to retain the advantageous material characteristics of halide perovskites, but with high thermodynamic stability and composed of earth-abundant and low toxicity elements. ABX ₃ chalcogenides (A, B=metals, X=Se, S) have been identified as potential class of materials meeting the aforementioned criteria. Methods: In this work, we focus on studying tin zirconium selenide (SnZrSe ₃) relevant physical properties with an aim to evaluate its prospects for application in optoelectronics. SnZrSe ₃ powder and monocrystals were synthesized via solid state reaction in 600 - 800 °C temperature range. Crystalline structure was determined using single crystal and powder X-ray diffraction methods. The bandgap was estimated from diffused reflectance measurements on powder samples and electrical properties of crystals were analysed from temperature dependent I-V measurements. Results: We found that SnZrSe ₃ crystals have a needle-like structure (space group - Pnma) with following unit cell parameters: a=9.5862(4) Å, b=3.84427(10) Å, c=14.3959(5) Å. The origin of the low symmetry crystalline structure was associated with stereochemical active electron lone pair of Sn cation. Estimated bandgap was around 1.15 eV which was higher than measured previously and predicted theoretically. Additionally, it was found that resistivity and conductivity type depended on the compound chemical composition. Conclusions: Absorption edge in the infrared region and bipolar dopability makes SnZrSe ₃ an interesting material candidate for application in earth-abundant and non-toxic single/multi-junction solar cells or other infrared based optoelectronic devices.

Keywords: ABX3 chalcogenides; bandgap; crystal structure; optoelectronic properties.

Grants and funding

This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 895046 (project Chalcopyrite-perovskites for infrared photovoltaics [IRPV]). This research was also supported by projects National Agency for Research and Development (ANCD) 20.80009.5007.15 and TK141 supported by European Union through the European Regional Development Fund, and by the Estonian Research Council under grant agreement No PRG1023.