Perovskites power up the solar industry
A promising material could deliver sunny days for renewable energy — if it can expand its reach
LAYER UP Researchers are betting on a class of sunlight-absorbing materials called perovskites to improve today’s solar cells. A perovskite’s cagelike crystal structure (right) surrounds a chunky ion such as methylammonium. The red, purple and orange balls are ions that can be varied so the material absorbs different wavelengths of light in its 3-D form (left).
T. Tibbitts; SOURCES: ROBERT J. CAVA/PRINCETON UNIV.; OSMAN M. BAKR AND OMAR F. MOHAMMED/SCIENCE 2017
Tsutomu Miyasaka was on a mission to build a better solar cell. It was the early 2000s, and the Japanese scientist wanted to replace the delicate molecules that he was using to capture sunlight with a sturdier, more effective option.
So when a student told him about an unfamiliar material with unusual properties, Miyasaka had to try it. The material was “very strange,” he says, but he was always keen on testing anything that might respond to light.
Other scientists were running electricity through the material, called a perovskite, to generate light. Miyasaka, at Toin University of Yokohama in Japan, wanted to know if the material could also do the opposite: soak up sunlight and convert it into electricity. To his surprise, the idea worked. When he and his team replaced the light-sensitive components of a solar cell with a very thin layer of the perovskite, the illuminated cell pumped out a little bit of