(Invited) Efficient and Stable Metal Halide Hybrid Perovskite Solar Cells

Abstract

Solar cells can generate free electricity by converting sunlight. Therefore, development of new solar cell materials with higher performance and lower cost fabrication are very important for realizing environmentally friendly and sustainable human society. Recently metal halide perovskites have emerged as the next-generation light absorber in solar cells. Power conversion efficiency of perovskite solar cells has already reached over 20%, which is comparable to existing silicon solar cell technology. However, several issues remain in perovskite solar cells, such as low operational stability under illumination, inclusion of toxic lead, and low thermal stability, and need to be solved for commercialization. Here we show our recent results on metal halide perovskite-based devices. We analyzed working and degradation mechanisms of perovskite solar cells with the aim of enhancing their solar power conversion efficiency and operational durability. The photon-to-electron conversion efficiencies and half lifetimes under continuous illumination for our lead-based perovskite solar cells reached high levels; > 20% and > 20,000 h. Mixing several metal, halogen, and organic ions greatly enhanced the thermal stability of perovskite films, making it possible to obtain perovskite solar cells showing less degradation even at 85 degree Celsius under illumination. We also demonstrated very stable solar cells based on tin-based perovskites with low toxicity. We also used perovskites to fabricate high mobility field-effect transistors, and efficient LEDs and laser devices. Figure 1