Researchers at Massachusetts Institute of Technology (MIT) and Stanford Univ. have developed a new kind of solar cell that combines two different layers of sunlight-absorbing material in order to harvest a broader range of the sun’s energy. The development could lead to photovoltaic cells that are more efficient than those currently used in solar-power installations, the researchers say.
The new cell uses a layer of silicon—which forms the basis for most of today’s solar panels—but adds a semi-transparent layer of a material called perovskite, which can absorb higher-energy particles of light. Unlike an earlier “tandem” solar cell reported by members of the same team earlier this year—in which the two layers were physically stacked, but each had its own separate electrical connections—the new version has both layers connected together as a single device that needs only one control circuit.
The new findings are reported in the journal Applied Physics Letters by MIT graduate student Jonathan Mailoa; associate professor of mechanical engineering Tonio Buonassisi; Colin Bailie and Michael McGehee at Stanford; and four others.