Fabrication performance and stability Analysis of the lead bismuth based Inverted planar device structured Perovskite solar cells

Abstract

Perovskite Solar Cells (PSCs) have recently emerged as a fourth-generation photovoltaic technology, Hybrid - combination of inorganic and organic components, that has attracted greater attention of the research community due to its incredible improvement in Power Conversion Efficiency (PCE) from 3.2% to 25.5% since 2009. The recent developments and implementations of PSCs suggest that this revolutionary photovoltaic technology will have a strong impact on the PV market in the near future. However, the low stability in ambient atmosphere and the presence of toxic Pb in PSCs are serious impediments for the commercialization of this technology. Herein, the work mainly focuses on the synthesis of Pb and Pb-free halide perovskite materials, fabricate the photovoltaic device structures and study their performance for photovoltaic applications. The optimization of perovskite layer deposition with improved surface morphology, solving the energy level mismatch by choosing a suitable hole transport layer, device fabrication of perovskite solar cells with the inverted device structure and analysis of their performance and stability are the main objectives of the present research work. Initially, this work focusses on improving the stability and performance of CH3NH3PbI3 PSCs by substituting inorganic Hole Transport Layers (HTLs) instead of organic HTLs in the inverted device structure. Since organic HTLs itself have low stability due to their hygroscopic and acidic nature, it further contributes to the degradation of the PSCs. The spray pyrolysis processed vanadium oxide (sp-VOx) have been introduced as a HTL and incorporated in the inverted device structured PSCs. In order to identify the surface morphology, structural and optical properties of the grown sp-VOx thin films and compare with other HTLs, different HTLs such as solution-processed VOx (sol-VOx), PEDOT: PSS and VOx/PEDOT: PSS (PVOX) HTLs have been grown on Flourine doped Tin Oxide (FTO) substrates. newline