Cu₂ZnSnS₄ chalcogenide semiconductor is a very promising absorber material for solar cells and no longer fulfilled its realistic goals due to the possible challenge of defect-free fabrication, non-optimized buffer layer alignment and device configuration. In this article, we proposed a new planner structure defined as (SnS/CZTS/TiO₂/ITO) using Ni and Al as a back and front contact materials, respectively, and simulated its photovoltaic (PV) performance using SCAPS-1D. In the simulation, defect densities were added to each layer and the interface between the buffer layer and the absorber layer. This work demonstrated the promising role of SnS HTL and TiO₂ ETL in reducing the V_oc deficit of CZTS-based solar cells by forming more favourable band alignment with the absorber layer, reducing non-radiative recombination at the interfaces. In response to changes in the material properties of different layers (such as thickness, carrier concentration, defect density), working temperature, and back contact metal work function, the PV performance of the new architecture for CZTS solar cells was investigated and optimized. The study of PV performance optimization revealed that a relatively thicker absorber layer with low carrier concentration showed better PV performances, while ETL and HTL with a thinner and higher carrier concentration are required to enhance PV performances. Power conversion efficiency of >30%, V_oc of >1.09 V, J_sc of >32 mA/cm² and FF of >87% was predicted for CZTS solar cells with the new architecture. The findings of this study suggest that SnS and TiO₂ are expected to become HTL and ETL, respectively, for fabricating low cost, high efficiency, and Cd-free CZTS-based heterojunction solar cell.

Cu ₂ ZnSnS ₄硫族化物半导体是一种非常有前途的太阳能电池吸收材料，由于可能会面临无缺陷制造，缓冲层未对准和器件结构优化的挑战，因此不再满足其现实目标。在本文中，我们提出了一种新的计划程序结构，定义为（SnS / CZTS / TiO ₂ / ITO），分别使用Ni和Al作为背面和正面接触材料，并使用SCAPS-1D模拟了其光伏（PV）性能。在模拟中，缺陷密度被添加到每一层以及缓冲层和吸收层之间的界面。这项工作证明了SnS HTL和TiO ₂ ETL在降低V _oc中的有希望的作用通过与吸收层形成更有利的能带对准，减少基于CZTS的太阳能电池的缺陷，减少了界面处的非辐射复合。响应于不同层的材料特性（例如厚度，载流子浓度，缺陷密度），工作温度和背接触金属功函数的变化，对CZTS太阳能电池新架构的PV性能进行了研究和优化。对光伏性能优化的研究表明，相对较厚的低载流子吸收层显示出更好的光伏性能，而要求ETL和HTL具有更薄和更高的载流子浓度才能增强PV性能。功率转换效率> 30％，V _oc > 1.09 V，J _sc > 32 mA / cm ²采用新架构的CZTS太阳能电池的FF预计> 87％。这项研究的发现表明，SnS和TiO ₂有望分别成为HTL和ETL，以制造低成本，高效率和无Cd的CZTS基异质结太阳能电池。