Quantum dot solar cells, the new revolution in solar energy

This nanoparticle technology, applied in a novel way to solar cells, has allowed a new world record to be set in the conversion of solar energy into electricity

If solar technology will once again be a safe bet in 2020 when it comes to investment and installation in renewable energy, innovation in this sector is not far behind either. And a new solar cell technology, based on a type of nanoparticle called “quantum dots”, has established a new world record for the conversion of solar energy into electricity for use by humans.

Quantum dot solar cells function as a “flexible skin” on hard surfaces, such as those found on a typical solar panel, as reported by Europa Press in a press release. According to Lianzhou Wang, a professor at the University of Queensland (Australia) and in charge of leading the research, these types of quantum dots are “flexible and printable” compared to the “rigid and expensive” materials currently used in the production of photovoltaic cells. Wang also predicts that this new material could open new doors, such as its use as “a transparent cover to power cars, airplanes, homes and portable technology.”

Despite all these wonders and advantages, this quantum dot technology has had to face a challenge in trying to overcome the fact that its surface is rough and unstable. Something that has not prevented this research team from improving, by 25%, the previous record of efficiency in converting solar to electrical energy.

What are quantum dots?

Quantum dots are, in general terms, a microscopic semiconductor structure (nanostructure) that traps the movement of electrons within the conduction band and the holes in the valence band, or excitons (bonding pairs of electrons in the conduction band and holes in the valence band), in all three spatial directions.

This technology, already present in fields as different from energy as biomedicine when it comes to detecting different cells, replacing current chemical developers due to their luminescent properties, has made its appearance in photovoltaics through solar cells, where the properties of these “little friends” are used to achieve the absorption of the sun’s rays. Specifically, their bandgap capacity (the energy difference between the upper part of the valence band and the lower part of the conduction band) that can be “tunable” depending on the energy level, makes them an attractive solution for multi-junction solar cell technologies, where different “bandgap” materials come together to improve the efficiency of solar energy collection. This is something that currently widespread materials such as silicon or copper selenide do not allow. This is what makes them so special.

Want to know more? Here we leave you a very interesting video about the applicability of these quantum dots in medicine: