Quantum dots reshape solar power capabilities

Quantum dot solar cells that can be used to generate electricity even in low-light conditions have been developed by researchers at The University of Queensland (UQ).

The researchers claim to have set a world record for the conversion of solar energy to electricity via the use of tiny nanoparticles called ‘quantum dots’, which pass electrons between one another and generate electrical current when exposed to solar energy in a solar cell device.

This development represents a significant step towards making the technology commercially viable and supporting global renewable energy targets.

Professor Lianzhou Wang, who led the breakthrough, said conventional solar technologies used rigid, expensive materials.

“The new class of quantum dots the university has developed are flexible and printable,” he said.

“This opens up a huge range of potential applications, including the possibility to use it as a transparent skin to power cars, planes, homes and wearable technology. Eventually it could play a major part in meeting the United Nations’ goal to increase the share of renewable energy in the global energy mix.”

Professor Wang’s team set the world record for quantum dot solar cell efficiency by developing a unique surface engineering strategy, overcoming previous challenges around the fact that the surfaces of quantum dots tend to be rough and unstable — making them less efficient at converting solar into electrical current.

“This new generation of quantum dots is compatible with more affordable and large-scale printable technologies,” Professor Wang said.

“The near 25% improvement in efficiency we have achieved over the previous world record is important. It is effectively the difference between quantum dot solar cell technology being an exciting ‘prospect’ and being commercially viable.”

UQ Vice-Chancellor and President Professor Peter Høj AC extended his congratulations to the UQ team.

“The world needs to rapidly reduce carbon emissions and this requires us to invest much more in research to improve existing energy-generation technologies and develop entirely new ones,” Professor Høj said.

“Harnessing the power of fundamental technological and scientific research is a big part of this process — and that’s what we’re focused on at UQ.”

The findings have been published in the journal Nature Energy.

The work was funded by the Australian Research Council’s Discovery Programs in collaboration with a number of colleagues both in Australian and overseas.

Top image caption: Quantum dot solution.