Researchers investigate the bulk photovoltaic effect in a promising material for future solar energy harvesting technologies.
The bulk photovoltaic (BPV) effect is a rare phenomenon that could allow certain materials to surpass the performance of traditional p–n junctions in solar cells. In a recent breakthrough, researchers in Japan have experimentally confirmed the BPV effect in alpha-phase indium selenide (α-In2Se3) along the out-of-plane direction for the first time, aligning with prior theoretical predictions. The impressive conversion efficiency achieved in their α-In2Se3 device represents a significant step forward for next-generation solar cell technologies and photosensors.
A firm understanding of the photovoltaic effect, by which light can be converted into useful electrical energy, lies at the core of solar cell design and development. Today, most solar cells employ p–n junctions, leveraging the photovoltaic effect that occurs at the interface of different materials. However, such designs are constrained by the Shockley–Queisser limit, which puts a hard cap on their theoretical maximum solar conversion efficiency and imposes a tradeoff between the voltage and current that can be produced via the photovoltaic effect.