Constant research and development efforts are allocated to eking out a smidgeon more of efficiency from the process of capturing sunlight and converting it to usable electricity, which could potentially save millions of dollars and make solar energy an even more attractive resource. The latest development comes from Lawrence Berkeley National Laboratory researchers, who discovered a new path to solar energy via solid-state photovoltaics, which acts as a way to vault the hurdle long posed by a bandgap voltage limitation inherent in conventional solid-state solar cells.
According to Berkeley Lab’s News Center, the researchers came upon a new mechanism that enables the photovoltaic effect to take place in semiconductor thin-films. The discovery came while the researchers were working with bismuth ferrite, a ceramic composed of bismuth, oxygen, and iron. What distinguishes bismuth ferrite from other currently used materials is its multiferroic property, which allows it to display both ferroelectric and ferromagnetic properties. While working with the bismuth ferrite, “the researchers discovered that the photovoltaic effect can spontaneously arise at the nanoscale as a result of the ceramic’s rhombohedrally distorted crystal structure.”
Additionally, applying an electric field enables the possibility of manipulating crystal structures, thereby allowing for the control of photovoltaic properties. The discoveries occurred in Berkeley Lab’s Helios Solar Energy Research Center, where the team of researchers applied white light to bismuth ferrite. The application made possible the generation of photovoltages within submicroscopic areas ranging from one and two nanometers across. In short: by bypassing the bandgap, an area in which no electrons can exist, Berkeley’s technology can allow for greater efficiency in solar devices.