Perovskite solar panels reach 25.6 percent conversion efficiency

Researchers worldwide have been working to optimize solar panels to allow more free clean energy to be gathered from the sun. One of the materials that researchers have been investigating as a potential replacement for conventional solar panels is perovskite. So far, the problem with perovskite solar panels and hybrid compounds is that they are less efficient than conventional solar panels.

Physical chemists and chemical engineers led by a team from the EPFL have announced a breakthrough in power-conversion efficiency and operational stability for perovskite solar cells. The team has achieved 25.6 percent efficiency in power conversion and operational stability of at least 450 hours. Perovskite is a hybrid compound made from metal halides and organic constituents.

The material has structural and electronic properties that place it at the forefront of material research with the potential for transforming a wide range of applications, including solar cells, LED lights, lasers, and photodetectors. Metal-halide perovskites are of particular interest to researchers for their potential as light harvesters for thin-film photovoltaics. The leading candidate among metal halide perovskites is formamidinium lead triiodide.

That material is seen as the most promising semiconductor for highly efficient and stable perovskite solar cells. The team of researchers uses a new chemical approach to greatly amplify the performance of formamidinium lead triiodide to achieve a power conversion efficiency of up to 25.6 percent with operational stability of at least 450 hours while providing intense electroluminescence.

The researchers say the external quantum efficiency, which is the amount of light the cell can produce when passing an electric current, exceeded 10 percent. The researchers say their findings provided a direct route to eliminate the most abundant and deleterious lattice defects present in mental halide perovskites.