Synthesis, Structure, and Thermoelectric Properties of Quaternary Selenides M 2 In 5 Sb 9 Se 23 (M = Sn, Pb) with NaCl-Type Ribbon Motifs
Year: 2026
Type: article
Abstract: High Resolution Image Download MS PowerPoint Slide Two quaternary selenides, M 2 In 5 Sb 9 Se 23 (M = Sn, Pb), were synthesized by solid-state routes and characterized by single-crystal and synchrotron powder X-ray diffraction. Both compounds crystallize in orthorhombic Pbam (No. 55) and comprise alternating NaCl-(111) ribbons of edge-sharing (In/Sb)Se 6 octahedra and NaCl-(100) ribbons of distorted (Pb/Sn/Sb)–Se polyhedra that pack in a herringbone-like structure feature. Diffuse-reflectance spectroscopy indicates a narrow optical gap of 0.91 eV for Pb 2 In 5 Sb 9 Se 23 . Transport measurements on cold-pressed, unoriented Pb 2 In 5 Sb 9 Se 23 indicate p-type semiconducting behavior with an Arrhenius activation energy of E a ∼ 0.25 eV, Seebeck coefficients up to +460 μV K –1 (≈440 K), and intrinsically low total thermal conductivity of ∼0.5 W m –1 K –1, yielding zT ∼ 0.005 at 440 K. Density functional calculations for both analogues predict an indirect band gaps and ribbon-localized band-edge states, suggesting anisotropic electronic transport. These results identify mixed NaCl-(111)/(100) ribbon assembly as a motif in multinary selenides and establish M 2 In 5 Sb 9 Se 23 as a useful platform for structure–property analysis and future thermoelectric optimization.
Source: Inorganic Chemistry
Authors: Yen-Han Huang, Guan-Ruei Chen, Chi-Shen Lee
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $4,500
Awards: G5191386505, G6066701144
OpenAlex ID: W7161113954