Inorganic CNTS as a potential hole-transport material for extremely stable and effective perovskite solar cells

In view of these distinctive properties, chalcogenide materials have attracted attention in response to the growing need for sustainable energy sources, with a particular focus on the efficient utilization of solar energy. One of the principal challenges associated with PSCslies in addressing the fill factor (FF) deficit and resolving stability concerns. Band alignment and resistance at the interface further reduce the fill factor, thereby limiting device performance. This research demonstrates that Cu2NiSnS4 (CNTS) can serve as an effective hole transport material for perovskite solar cells, offering an enhanced stability. In this study, kesterite-based CNTS is utilized as a hole-selective interlayer in inverted CH3NH3PbI3 perovskite solar cells (PSCs) on ITO/CNTS substrates. CNTS was selected due to its numerous advantages, including the abundance of their constituent elements in nature, non-toxicity, cost-effectiveness, appropriate band gap and absorption coefficient for photovoltaic (PV) applications, as well as their tunable band gap properties. Deposition of CNTS onto ITO glass alters the substrate's work function, resulting in open-circuit voltages exceeding 1.0 V. Solar cells on ITO substrates without a metal oxide layer demonstrated an exceptional power conversion efficiency (PCE) of 10.6 %. This highlights the potential of PSCs for high performance with a single selective contact. Our findings reveal that these cells retain over 93 % of their initial efficiency after 720 h, demonstrating improved stability. Replacing p-type organic materials with inorganic counterparts offers a promising avenue for further research.