Photoelectric performance of environmentally benign Cs2TiBr6-based perovskite solar cell using spinel NiCo2O4 as HTL

Compositional engineering strives to build low-cost, efficient solar cells with higher performance and stability. This simulation focused on the Pb-free environmentally friendly Cs2TiBr6 perovskite layer. Another important topic to be explored here is spinel NiCo2O4 as a hole transport material. The proposed device structure is FTO/TiO2/Cs2TiBr6/NiCo2O4/Au. The optimum perovskite layer thickness was found at 700 nm. The thickness of the electron transport layer and the hole transport layer, which acts as a charge transport layer, had a minor influence on performance. Positive band offset for the conduction and valance bands resulted in higher efficiency. Spike in the band structure decreased the carrier recombination. Both the donor and acceptor doping density of 1019 cm─3 provides the maximum PCE (Power Conversion Efficiency) of 19.3%. The interface defect tolerance limit was found 1014 cm─2. Radiative recombination co-efficient play’s an important role on device performance. The electrical field within solar cells controls charge carrier dynamics and performance. Gold as back contact exhibits maximum power conversion efficiency. The proposed structure shows good thermal stability with temperature degradation co-efficient, CT of ─ 0.20881% K─1. Due to the high built-in potential (Vbi) value, the proposed structure can retain 80% of its efficiency at higher temperatures. At optimum operational conditions, maximum output is Voc = 1.32 V, Jsc = 17.67 mA/cm2, FF = 82.51%, and PCE = 19.3%. This device would be a better option for commercialization regarding performance and stability concerns. Real-world device fabrication would provide a more in-depth understanding of the device. [Display omitted] •An optimized device based on the environmentally benign Cs2TiBr6 perovskite solar cell achieves 19.3 % PCE.•For Cs2TiBr6-based PSCs, spinel NiCo2O4 appears to be a potential HTL.•The structure shows very good thermal stability and the temperature degradation co-efficient, CT is ─ 0.20881 K─1.•Excellent acceleration of photogenerated carriers in opposing directions because of the high built-in potential values.•High defect tolerance limit for real device fabrication for at both interfaces indicates superior material combination.