All-perovskite tandem solar cells from fundamentals to technological progress

Abstract

Organic-inorganic perovskite materials have gradually progressed from single-junction solar cells to tandem (double) or even multi-junction (triple-junction) solar cells as all-perovskite tandem solar cells (APTSCs) have advantages: (1) the tunable optical bandgap, (2) low-cost because of solution-processing, inexpensive precursors, and thin film process, (3) scalability and lightweight, and (4) an eco-friendly technology related to low CO2 emission. However, APTSCs face severe issues regarding stability caused by Sn2+ oxidation in narrow bandgap perovskites, low performance due to Voc deficit in the wide bandgap range, non-standardisation of charge recombination layers, and a challenging thin-film deposition as each layer must be nearly perfectly homogenous. Here, we discuss the fundamentals of APTSCs and technological progress for each layer of the all-perovskite stacks. Furthermore, the theoretical power conversion efficiency (PCE) limitation of APTSCs is discussed by utilising simulation research.