A new material capable of greatly improving the efficiency of solar power systems reportedly raised the quantum efficiency of solar panels to an unprecedented 190% during recent tests.
A prototype was developed by researchers with Lehigh University with funding from the U.S. Department of Energy, which features an active layer in a solar cell using the material that reportedly also achieved an average photovoltaic absorption of close to 80%.
Photovoltaic (PV) systems are electric systems that can provide usable solar power, usually involving solar panels that collect sunlight and convert it into electricity. Additional components include a solar inverter used to convert the power output into alternating current that can be used to power conventional devices.
Traditional solar cells possess a maximum external quantum efficiency (EQE) of 100%, which means they can generate and collect a single electron for each photon they absorb through sunlight collected. In recent years, advancements in materials used for such systems have shown promise for increased generation and collection of electrons from high-energy photons.
The efficiency displayed by the new prototype tested by the Lehigh University team far exceeds the current theoretical limits for conventional silicon-based materials used in such PV systems and could potentially revolutionize the field involving the quantum materials they rely on.
Chinedu Ekuma, a physics professor specializing in computational condensed matter physics, says experiments with the new material mark a significant leap toward the development of novel energy solutions that are both more sustainable and accessible.
Ekuma and the team behind the discovery attribute the new material’s remarkable capabilities to what the refer to as “intermediate band states,” which involve certain energy levels that are built into the material’s electronic structure, helping to optimize their ability to convert solar energy.
These intermediate band states have energy levels that align with optimal energy ranges of 0.78 and 1.26 electron volts, where the material can absorb sunlight and produce a charge. Known as subband gaps, these energy ranges are ideal for use in creating materials capable of efficient sunlight absorption.
In addition to its capabilities with visible light, the Ekuma and his team report that the new material is also capable of absorbing energy from infrared as well.
New materials developed in recent years that increase the generation and collection of electrons from high-energy photons rely on what are called Multiple Exciton Generation (MEG) materials, which are still nascent and have yet to see regular use in commercial applications. However, they hold promise for a new breed of solar power systems in the years ahead.
The material developed by Ekuma and the Lehigh team utilizes its unique design and use of intermediate band states to capture energy that is normally lost in conventional solar power systems.
Specifically, the team leveraged what physicists call van der Waals gaps, which are tiny, atomic-width gaps between layered two-dimensional materials that confine molecules or ions. These gaps provide just enough space to allow the insertion of other elements that allow a greater degree of control.
In their creation of the new material, Ekuma and the team intercalated zerovalent copper atoms into the tiny gaps between layers of 2D material composed of germanium selenide (GeSe) and tin sulfide (SnS).
Ekuma says the material’s rapid response and increased efficiency “strongly indicate the potential of Cu-intercalated GeSe/SnS as a quantum material for use in advanced photovoltaic applications,” adding that the material’s performance could help to facilitate a new “avenue for efficiency improvements in solar energy conversion.”
Integration of the new prototype into contemporary solar energy systems will still require a bit of time, as Ekuma and the team say additional research will be necessary in order to determine how their material can be applied for such uses.
However, the refinement scientists have harnessed in the insertion of atoms, ions, and molecules into materials is likely to help speed the process and will lead to additional advancements in solar power generation.
Ekuma called the new prototype “a promising candidate for the development of next-generation, high-efficient solar cells, which will play a crucial role in addressing global energy needs.”
A new paper describing the team’s findings appeared in the journal Science Advances.
Micah Hanks is the Editor-in-Chief and Co-Founder of The Debrief. He can be reached by email at micah@thedebrief.org. Follow his work at micahhanks.com and on X: @MicahHanks.