Insights in Perovskite Solar Cell Fabrication: Unraveling the Hidden Challenges of Each Layer

Abstract

Perovskite solar cells (PSC) are undoubtedly the most active research area in photovoltaics at this moment. Actually, since 2009 this emerging technology passed from 3.8% to the present >22% of energy conversion efficiency. Along with that, a huge amount of sometimes contradicting and incomplete information about how to prepare and characterize PSC is provided, which makes it difficult to not get lost. This paper is mainly directed toward newcomers in this area, with the goal to give orientation for PSC fabrication protocols that are quickly implementable and that lead to reliable and acceptable efficiencies. Therefore, a step-by-step analysis of each layer is provided and, within this scope, several fabrication techniques are compared in terms of efficiency optimization. Furthermore, a new and versatile alternative to laser-assisted scribing for substrate patterning is presented. Electrochemical characterization of dummy cells as an easy and versatile tool for isolated layer characterization is demonstrated for TiO2 blocking layers. After optimization of each layer, PSC with an average efficiency of (14.8 +/- 1.0)% was obtained.