Researchers at Martin Luther University Halle-Wittenberg (MLU) and Leibniz Institute of Surface Engineering (IOM) have discovered a new method to increase the efficiency of solar cells by a factor of 1,000. They achieved this breakthrough by creating crystalline layers of barium titanate, strontium titanate, and calcium titanate, which were alternately placed on top of one another in a lattice structure.
Their findings, which could revolutionize the solar energy industry, were recently published in the journal Science Advances.
As summarized in Brighter News (April 15, 2023), solar cells currently in use are mostly silicon-based, but their efficiency is limited. This has led researchers to explore new materials, such as ferroelectrics like barium titanate, which is a mixed oxide made of barium and titanium. Ferroelectric materials have spatially separated positive and negative charges, which leads to an asymmetric structure that generates electricity from light. Unlike silicon, ferroelectric crystals do not require a pn junction to create the photovoltaic effect, making it easier to produce solar panels. However, pure barium titanate does not absorb much sunlight, resulting in a relatively low photocurrent. The new research has shown that combining extremely thin layers of different materials significantly increases the solar energy yield.