Tuning perovskite solar-cell absorbers by giving them a squeeze

Solar cells are among the most established and widely-utilized alternative energy technologies due to their relative affordability and ease of integration into existing infrastructure. Inexpensive materials called hybrid perovskites show great promise as solar-cell absorbers, and they are getting more and more efficient. This week in ACS Central Science, researchers reveal they can improve the performance of these materials simply by applying external pressure.

Perovskites are minerals that come in several types of structures, including hybrid ones that incorporate organic components. Lead-halide hybrid perovskites can efficiently absorb sunlight in a solar cell. Hemamala Karunadasa, Wendy Mao and colleagues sought to assess how pressure affects the manner in which these materials respond to light. The researchers found that compression changes the materials' bandgaps, which can allow scientists to tailor the wavelength of absorbed light. Compression can further increase the obtainable voltage from perovskite solar cells, and it also dramatically increases the materials' electronic conductivity. This work shows that pressure is a tuning knob for improving the properties of perovskite absorbers.

Source: American Chemical Society