
Engineering
24 Feb 2021
Buckyballs on DNA for harvesting light
Supramolecular structure boosts efficiency of light harvesting for solar cells By Mischa Dijkstra, Frontiers science writer Researchers from the Karlsruhe Institute of Technology show that DNA can serve as a scaffold for light-harvesting supramolecules, where fluorescent dyes work as electron donors and buckyballs as electron acceptors. The DNA’s regular 3D structure increases the light-to-electrons conversion efficiency by reducing so-called self-quenching. Such DNA-based supramolecules could be used in future organic solar cells. Image: Yes058 Montree Nanta/Shutterstock Organic molecules that capture photons and convert these into electricity have important applications for producing green energy. Light-harvesting complexes need two semiconductors, an electron donor and an acceptor. How well they work is measured by their quantum efficiency, the rate by which photons are converted into electron-hole pairs. Quantum efficiency is lower than optimal if there is “self-quenching”, where one molecule excited by an incoming photon donates some of its energy to an identical non-excited molecule, yielding two molecules at an intermediate energy state too low to produce an electron-hole pair. But if electron donors and acceptors are better spaced out, self-quenching is limited, so that quantum efficiency improves. In a new paper in Frontiers in Chemistry, researchers from the Karlsruhe Institute of Technology (KIT) […]