Solar Cell Materials by Design: Hybrid Pyroxene Corner-Sharing VO4 Tetrahedral Chains

Abstract

Hybrid organic-inorganic frameworks provide numerous combinations of materials with a wide range of structural and electronic properties, which enable their use in various applications. In recent years, some of these hybrid materials-especially lead-based halide perovskites-have been successfully used for the development of highly efficient solar cells. The large variety of possible hybrid materials has inspired the search for other organic-inorganic frameworks that may exhibit enhanced performance over conventional lead halide perovskites. In this study, a new class of low-dimensional hybrid oxides for photovoltaic applications was developed by using electronic structure calculations in combination with analysis from existing materials databases, with a focus on vanadium oxide pyroxenes (tetrahedron-based frameworks), mainly due to their high stability and nontoxicity. Pyroxenes were screened with different cations [A] and detailed computational studies of their structural, electronic, optical and transport properties were performed. Low-dimensional hybrid vanadate pyroxenes [A]VO₃ (with molecular cations [A] and corner-sharing VO₄ tetrahedral chains) were found to satisfy all physical requirements needed to develop an efficient solar cell (a band gap of 1.0-1.7 eV, strong light absorption and good electron-transport properties).

Keywords: density functional calculations; organic-inorganic hybrid composites; photovoltaics; solar cells; vanadium.