Kesterite Thin‐Film Solar Cells: Advances in Materials Modelling of Cu₂ZnSnS₄

Abstract

2 based technologies. Zinc-blende related structures are formed by quaternary compounds, but the complexity associated with the multi-component system introduces diffi culties in material growth, characterization, and application. First-principles electronic structure simulations, performed over the past fi ve years, that address the structural, electronic, and defect properties of this family of compounds are reviewed. Initial predictions of the bandgaps and crystal structures have recently been verifi ed experimentally. The calculations highlight the role of atomic disorder on the cation sub-lattice, as well as phase separation of Cu 2 ZnSnS 4 into ZnS and CuSnS 3 , on the material performance for light-to-electricity conversion in photovoltaic devices. Finally, the current grand challenges for materials modeling of thin-fi lm solar cells are highlighted. 401 www.MaterialsViews.com www.advenergymat.de

Kësterite thin films for photovoltaics : a review

“…Due to their structural similarities, kësterite and stannite are very difficult to distinguish by X-Ray Diffraction and Raman spectroscopy, and it is necessary to use neutron diffraction [36,37] to tell them apart. According to ab initio calculi, the most stable crystalline structure is kësterite [38][39][40][41][42] and one study by ab initio calculation even suggests that all observations of stannite structure for CZTS compounds were due to partial disorder in the I-II (001) layer of the kësterite phase [32]. Recent neutron diffraction [37] and anomalous diffusion [43] characterizations show that CZTS crystallizes in the kësterite structure, and synchrotron X-Ray experiments show that this structure is dominant for temperature <876…”

Opposing effects of stacking faults and antisite domain boundaries on the conduction band edge in kesterite quaternary semiconductors

“…Thin-film photovoltaic devices based on Cu 2 ZnSn(S,Se) 4 (CZTSSe) absorber layers have attracted growing attention [1][2][3] as the materials are composed of earth-abundant elements [4], which are not categorized as critical raw materials (CRM) by EU [5]. The system has a tuneable direct band gap of 1.0 ∼ 1.5 eV [6], which is ideal for single junction solar cell applications [7].…”

Structural and electronic properties of hybrid perovskites for high-efficiency thin-film photovoltaics from first-principles

“…7 The conversion efficiencies have quickly surpassed both those of conventional dye-cells, as well as next-generation thin-film absorbers such as Cu 2 ZnSnS 4 . 8,9 Despite their high-performance for small area (∼0.2 cm 2 ) cells, the underlying material properties are largely unknown, which could help with producing more robust large-area devices.…”