Solar cells that rely on perovskites to harvest sunlight are bound to gain in energy conversion efficiency thanks to an atomic-level understanding of the structure-property relationship of these photovoltaic materials. Researchers from the KAUST Solar Center monitored the impact of compositional changes on the structural organization and photovoltaic properties of perovskite thin films in situ. For more information see the IDTechEx report on Perovskite Photovoltaics 2018-2028.

 

Hybrid perovskites have emerged as key components in low-cost, high-efficiency solar cells because they are cheaper and easier to process than traditional silicon-based solar cell materials. In addition, they exhibit unique optoelectronic characteristics, including high light absorption and a defect tolerance that lead to solar cells with maximum power-conversion efficiencies of 24 to 28 percent when used alone or in tandem combination with silicon. They also outperform single-junction silicon solar cells.

 

Solar cell performance and stability depend on the morphology of the thin films, especially their ability to crystallize in the so-called photoactive α-phase. Perovskites containing lead tend to combine various halides, such as the anionic forms of bromine and iodine, with mixtures of methylammonium, formamidinium, cesium and other cations. These have led to record conversion efficiencies and thermal stabilities compared with their single-halide, single-cation analogs. However, these mixed-halide, mixed-cation perovskite films have been characterized only through ex-situ postdeposition techniques. This limits the understanding of the mechanisms that govern their growth from their sol-gel precursor to their solid state and stalls attempts to improve device performance and stability.

 

Learn more at the next leading event on the topic: Printed Electronics USA 2019 External Link on 20 – 21 Nov 2019 at Santa Clara Convention Center, CA, USA hosted by IDTechEx.