Perovskite solar cells: Materials, configurations and stability

Perovskite solar cells (PSC) have recently emerged as a strong contender for the next generation of photovoltaic technologies, having received the attention of the photovoltaic community, both scientists and industry. In few years, power conversion efficiency of PSCs reached already 22%. A broad range of architectures and fabrication methods have been proposed, as well as several perovskite compositions and charge selective layers, suggesting that the performance of these devices is still far from being fully optimized. PSCs still exhibiting stability problems and the most efficient absorbers incorporate lead (ca. 13 mg m(-2)). Moreover, PSCs are sensitive to high temperatures, UV-light, moisture and oxygen: factors that are hindering their commercialization. The present review frames the last attempts for overcoming these challenges addressing degradation mechanisms and outlining the outstanding achievements. This article also reviews the basic working principles of PSCs, addresses new cell configurations, highlights the need of leak-free encapsulation for long-term stability and environmentally safer devices, and discusses new and lead-free absorbers.