Researchers use nanomaterials-based technology to increase PV cell efficiency up to 45%

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  Embedding charged quantum dots into solar cells can improve electrical output by enabling the cells to harvest infrared light and thereby increasing the lifetime of photoelectrons, claim researchers.
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  Researchers from the University at Buffalo and US army institutes have developed a new, nanomaterials-based technology that has the potential to increase the efficiency of PV cells up to 45%.

Researchers from the University at Buffalo, Army Research Laboratory and Air Force Office of Scientific Research have developed a new, nanomaterials-based technology that has the potential to increase the efficiency of PV cells up to 45%. The researchers have also teamed up to found OPtoElectronic Nanodevices to commercialize this technology and are now seeking funding from private investors and federal programs. Through UB's office of science, technology transfer and economic outreach (STOR), the team has filed provisional patent applications to protect their technology.

The research appeared online last May in the journal Nano Letters. The research team included Vladimir Mitin, Andrei Sergeev and Nizami Vagidov, faculty members in UB's electrical engineering department; Kitt Reinhardt of the air force office of scientific research and John Little and advanced nanofabrication expert Kimberly Sablon of the US army research laboratory.

The researchers have shown that embedding charged quantum dots into solar cells can improve electrical output by enabling the cells to harvest infrared light and thereby increasing the lifetime of photoelectrons. The technology can be applied to many different PV structures.

The UB researchers and their colleagues claim to have not only successfully used embedded quantum dots (dubbed Q-BICs) to harvest infrared light, they have also taken the technology a step further, employing selective doping so that quantum dots within the solar cell have a significant built-in charge. This is beneficial because it repels electrons, forcing them to travel around the quantum dots. Otherwise, the quantum dots create a channel of recombination for electrons, in essence "capturing" moving electrons and preventing them from contributing to electric current.

According to Mitin, the idea of embedding quantum dots into solar panels is not new. About a decade ago, scientists had proposed that this technique could improve efficiency by allowing panels to harvest invisible, infrared light in addition to visible light. However, efforts in this direction have previously met with limited success.

“Clean technology will really benefit the region, the state, the country," Mitin said. “With high-efficiency solar cells, consumers can save money and providers would have a smaller solar field that produces more energy.”

The University at Buffalo is a research-intensive public university. UB's more than 28,000 students pursue their academic interests through more than 300 undergraduate, graduate and professional degree programs. Founded in 1846, the University at Buffalo is a member of the Association of American Universities.