Recent Progress on Cu2BaSn(SxSe1-x)(4): From Material to Solar Cell Applications

Thin film solar cells show great potential applications in building-integrated photovoltaics (BIPV) and portable devices. Among these thin film solar cells, Cu2BaSn(SxSe1-x)(4)solar cells derived from Cu2ZnSn(SxSe1-x)(4)solar cells have attracted intense research interests recently because of their high theoretical PCE of ap;31%, easy tunability of band gaps (E-g = 1.28-1.79 eV), large optical absorption coefficient (alpha > 10(4 )cm(-1)), environment-friendly composition, low materials, and fabrication cost. Importantly, Cu2BaSn(SxSe1-x)(4)solar cells are expected to have low open-circuit voltage deficit, leading to high open-circuit voltage and PCEs. In fact, since their initial development in 2016, the maximum PCE of Cu2BaSn(SxSe1-x)(4)solar cells has surpassed 5% via adjustment of the fabrication methods and material properties, optimization of the device structures, and so forth. Here, a review of the recent progress of Cu2BaSn(SxSe1-x)(4)solar cells is presented, including properties of Cu2BaSn(SxSe1-x)(4), material and device fabrication methods, device performances, potential applications, as well as the bulk and interface recombination. In addition, other solar cells which are similar with the Cu2BaSn(SxSe1-x)(4)solar cells are also discussed. Finally, according to these discussions, prospect for PCEs improvement is given to accelerate their development.