ABSTRACT

This paper discusses the impact of the p-MoS₂ transition metal dichalcogenide as an interfacial layer between the CZTS absorber and Mo back contact in the CZTS based solar cell. The study was performed using SCAPS-1D numerical simulation. The I–V characteristic demonstrated a higher slope than CZTS solar cells without considering the interfacial layer. The results verified that the p-MoS₂ layer beneficially on the CZTS/Mo hetero-contact mediating an ohmic contact. Accordingly, the conversion efficiency improves from 12.14% to 16.71%. To evaluate the role of the p-MoS₂ layer, various performance parameters such as open-circuit voltage (V_oc), short circuit current (J_sc), fill factor FF, and efficiency η were explored versus thicknesses, bandgap energies, and the acceptor carrier concentration (N_A). The results show that a thickness of the interfacial layer of less than 200 nm could cause deterioration of the overall cell performance, mainly due to created high barriers at the CZTS/p-MoS₂ and p-MoS₂/Mo interfaces, at low thicknesses, which impedes the drift of photogenerated holes. Additionally, increasing the N_A above 10¹⁶ cm⁻³ improves the cell performance, owing to the favourable band alignment at the back contact. Values obtained for V_oc and J_sc are 0.88 V and 25.5 mA/cm², respectively. Moreover, the effect of series resistance R_s on CZTS solar cells was investigated. The efficiency decreases from 12.84% to 9.69% when the R_s correspondingly increases from 0 Ω to 5 Ω.

摘要

本文讨论了在基于 CZTS 的太阳能电池中，p-MoS ₂ 过渡金属二硫属化物作为 CZTS 吸收剂和 Mo 背接触之间的界面层的影响。该研究使用 SCAPS-1D 数值模拟进行。在不考虑界面层的情况下，I-V 特性表现出比 CZTS 太阳能电池更高的斜率。结果证实，p-MoS ₂ 层有益于介导欧姆接触的CZTS/Mo异质接触。因此，转换效率从 12.14% 提高到 16.71%。为了评估 p-MoS ₂ 层的作用，各种性能参数，例如开路电压 (V _oc )、短路电流 (J _sc)、填充因子 FF 和效率 η 与厚度、带隙能量和受主载流子浓度 (N _A ) 的关系进行了探索。结果表明，小于 200 nm 的界面层厚度可能导致整体电池性能下降，这主要是由于在 CZTS/p-MoS ₂ 和 p-MoS ₂ /Mo 界面处形成的高势垒，在低厚度，这阻碍了光生空穴的漂移。 此外，由于背接触处有利的能带排列，将N _A增加到 10 ¹⁶  cm ^{-3以上提高了电池性能。}V _oc 和 J _sc获得的值为 0.88 V 和 25.5 mA/cm ²， 分别。此外，还研究了串联电阻 R _s 对 CZTS 太阳能电池的影响。当 R _s 相应地从 0 Ω 增加到 5 Ω 时，效率从 12.84% 下降到 9.69%。