Ultrathin solar cells assure enhanced satellite performance

• The majority of space satellites are powered by photovoltaic cells that convert sunlight to electrical energy. Direct exposure to particular types of radiation present in orbit can harm the devices, degrading their performance and restricting their lifetime.

In the Journal of Applied Physics, researchers from the University of Cambridge proposed a radiation-tolerant photovoltaic cell design that features an ultrathin layer of light-absorbing material.

When solar cells absorb light, they transfer its power to adversely charged electrons in the material. These cost carriers are knocked free and generate a flow of power across the photovoltaic or pv. Irradiation in space creates damage as well as reduces performance by displacing atoms in the solar cell material and also reducing the lifetime of the fee carriers. Making photovoltaics thinner need to raise their durability due to the fact that the cost carriers have much less far to go during their shortened lifetimes.

As low Earth orbit comes to be a lot more littered with satellites, it becomes progressively essential to make use of center Earth orbits, such as the Molniya orbit that travels through the center of Earth's proton radiation belt. Radiation-tolerant cell designs will be needed for these higher orbits.

Another application for radiation-tolerant cells is the research of other planets as well as moons. For example, Europa, a moon of Jupiter, has one of the most severe radiation settings in the solar system. Landing a solar-powered spacecraft on Europa will require radiation-tolerant devices.

The investigators constructed 2 kinds of solar devices using the semiconductor gallium arsenide. One was an on-chip design constructed by layering numerous compounds in a pile. The other design included a silver back mirror to enhance light absorption.

To mimic the effects of radiation precede, the devices were bombarded with protons generated at the Dalton Cumbrian Nuclear Facility in the U.K. The performance of the photovoltaic or pv devices before and after irradiation was examined using a technique known as cathodoluminescence that can give a procedure of the amount of radiation damage. A 2nd collection of examinations utilizing a Compact Solar Simulator were performed to figure out how well the devices converted sunlight to power after being bombarded with protons.

"Our ultra-thin solar cell outperforms the formerly examined, thicker devices for proton radiation above a certain threshold. The ultra-thin geometries offer favorable performance by 2 orders of magnitude about previous observations," stated author Armin Barthel.

The authors claimed that the boosted performance of these ultra-thin cells is because the charge carriers live long enough to travel between terminals in the device.

Contrasted to thicker cells, virtually 3.5 times less cover glass is needed for the ultra-thin cells to deliver the same amount of power after twenty years of operation. This will certainly convert to a lighter tons as well as substantial decrease in launch costs.

The article "Radiation effects in ultra-thin GaAs solar cells" is authored by Armin Barthel, Larkin Sayre, Gunnar Kusch, Rachel A. Oliver, as well as Louise C. Hirst. The article will certainly appear in Journal of Applied Physics on Nov. 8, 2022.