Jul 25, 2017

Researchers affiliated with UNIST, the Korea Institute of Chemical Technology (KRICT) and Hanyang University have designed a cost-efficient method to produce inorganic-organic hybrid perovskite solar cells (PSCs), with outstanding efficiency performance of 22.1% in small cells and 19.7% in 1-square-centimeter cells.

UNIST's highly efficient perovskite PSCs image

A key feature of this technology is its ability to tackle the dominating defect in perovskite-halides, which is known to decrease the photoelectric efficiency. The team's results demonstrate that careful control of the growth conditions of perovskite layers with management of deficient halide anions is essential for realizing high-efficiency thin-film PSCs based on lead-halide-perovskite absorbers.

In this study, the research team demonstrated the introduction of additional iodide ions into the organic cation solution, which are used to form the perovskite layers through an intramolecular exchanging process, decreases the concentration of deep-level defects. The result showed that the defect-engineered thin perovskite layers enable the fabrication of PSCs with a certified power conversion efficiency of 22.1% in small cells and 19.7% in 1-square-centimeter cells.

The energy conversion efficiency of those PSCs with reduced defects is 22.1% and has been officially certified by the National Renewable Energy Laboratory (NREL).