Synthesis, Properties and Applications of Lead-Free Perovskites:A Review

Perovskites are the materials or compounds having a structure similar to calcium titanium oxide (CaTiO3). These materials possess the basic structure of ABX3, in which A & B are the cations with +1 and +2 electron vacancy and X is an anion which may be either halogen or oxygen. Perovskites are chiefly being used in solar cells in the photo absorbing layer for solar to electrical energy conversion with relatively high efficiencies, besides their use in LEDs, photodetectors, X-ray detectors, lasers etc. The power conversion efficiency (PCE) of Perovskite solar cell (PSC) has increased from 10% in the year 2012 to 29.1% in 2020 and are promising to cross the theoretical maximum (Shockley-Queisser) limit of 33% for conventional silicon solar cells, besides having great thermal and mechanical stability values. Toxicity due to the presence of lead and associated instability of PSCs have led to the intensive research in lead-free perovskite solar cells (LF-PSCs). In this review article we have tried to explore the current status of synthesis, properties and applications of perovskites in PSCs,particularly lead-free perovskites, and will suggest future prospects in this widely attracted field of non-conventional energy generation.