%0 Journal Article
%T Solar Energy Storage by Molecular Norbornadiene¨CQuadricyclane Photoswitches: Polymer Film Devices
%A Anna I. Hofmann
%A Anne Ugleholdt Petersen
%A Christian M¨¹ller
%A Christopher J. Sumby
%A Mads Mans£¿
%A Martyn Jevric
%A M¨¦ritxell Fillols
%A Zhihang Wang
%J Archive of "Advanced Science".
%D 2019
%R 10.1002/advs.201900367
%X Devices that can capture and convert sunlight into stored chemical energy are attractive candidates for future energy technologies. A general challenge is to combine efficient solar energy capture with high energy densities and energy storage time into a processable composite for device application. Here, norbornadiene (NBD)¨Cquadricyclane (QC) molecular photoswitches are embedded into polymer matrices, with possible applications in energy storing coatings. The NBD¨CQC photoswitches that are capable of absorbing sunlight with estimated solar energy storage efficiencies of up to 3.8% combined with attractive energy storage densities of up to 0.48 MJ kg£¿1. The combination of donor and acceptor units leads to an improved solar spectrum match with an onset of absorption of up to 529 nm and a lifetime (t 1/2) of up to 10 months. The NBD¨CQC systems with properties matched to a daily energy storage cycle are further investigated in the solid state by embedding the molecules into a series of polymer matrices revealing that polystyrene is the preferred choice of matrix. These polymer devices, which can absorb sunlight and over a daily cycle release the energy as heat, are investigated for their cyclability, showing multicycle reusability with limited degradation that might allow them to be applied as window laminates
%K heat release
%K solar energy storage
%K solar thermal
%K solid state materials
%U https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6662068/