Efficient Design and Fabrication of Cs₂TiBr₆-Based HTL-Free Solar Cells

Conventional perovskite solar cells (PSCs) have improved significantly in performance, but the presence of toxic lead (Pb) has prevented their commercialization. This study presents a systematic approach for designing and analysing solar cells using Cs₂TiBr₆. The synthesis process involves the precise formulation of c-TiO₂, mp-TiO₂, and Cs₂TiBr₆. Spin-coating on fluorine-doped tin oxide yields efficient hole-transport-free PSCs. X-ray diffraction (XRD) analysis confirms the crystallinity, optical assessments reveal a 1.8 eV energy band, and field-emission scanning electron microscopy (FESEM) imaging showcases organized perovskite grain structures vital for charge transfer. These lead-free PSCs demonstrate promising performance metrics, offering an environmentally conscious path for advancing and adopting PSC technology. With a significant V_oc of 0.89 V, effective charge separation, and PCE of 2.34%, Cs₂TiBr₆ exhibits the potential for use in eco-friendly photovoltaics and diverse optoelectronic applications.