There may be many ignored natural and inorganic materials that might be utilized to harness sunlight underwater and effectively power autonomous submersible vehicles, report researchers at New York University (NYU). Their analysis, appearing March 18 in the journal Joule, prepared tips for utmost bandgap values at a level of watery depths, showing that various wide-bandgap semiconductors, rather than the narrow-band semiconductors utilized in traditional silicon solar cells, are best outfitted for underwater usage.
Underwater vehicles, such as these utilized to explore the abyssal ocean, are currently limited by onshore power or inefficient on-board batteries, stopping travel over longer distances and periods of time. However, while photovoltaic cell technology that has already suspended on land and in outer space could give these submersibles more liberty to roam, the watery world prose novel challenges.
Water absorbs much of the visible light, grasping red photovoltaic wavelengths even at shallow depths before silicon-based solar cells would capture them.
Most earlier attempts to build underwater solar cells have been developed from silicon or amorphous silicon, which each has narrow band gaps best suited for grasping light on the land. Nevertheless, blue and yellow light manages to insert deep into the water column even as other wavelengths disappear, suggesting semiconductors with wider bandgaps not found in conventional solar cells might present a better fit for supplying power underwater.