Kuisma Mikael, Lundin Angelica, Moth-Poulsen Kasper, Hyldgaard Per, Erhart Paul
Department of Physics, Chalmers University of Technology, Gothenburg, Sweden.
Department of Chemistry and Chemical Engineering, Chalmers University of Technology, Gothenburg, Sweden.
ChemSusChem. 2016 Jul 21;9(14):1786-94. doi: 10.1002/cssc.201600281. Epub 2016 Jun 2.
Molecular photoswitches capable of storing solar energy are interesting candidates for future renewable energy applications. Here, using quantum mechanical calculations, we carry out a systematic screening of crucial optical (solar spectrum match) and thermal (storage energy density) properties of 64 such compounds based on the norbornadiene-quadricyclane system. Whereas a substantial number of these molecules reach the theoretical maximum solar power conversion efficiency, this requires a strong red-shift of the absorption spectrum, which causes undesirable absorption by the photoisomer as well as reduced thermal stability. These compounds typically also have a large molecular mass, leading to low storage densities. By contrast, single-substituted systems achieve a good compromise between efficiency and storage density, while avoiding competing absorption by the photo-isomer. This establishes guiding principles for the future development of molecular solar thermal storage systems.
能够存储太阳能的分子光开关是未来可再生能源应用的有趣候选者。在此，我们利用量子力学计算，对基于降冰片二烯-四环烷体系的64种此类化合物的关键光学（太阳光谱匹配）和热学（储能密度）性质进行了系统筛选。虽然这些分子中有相当一部分达到了理论上的最大太阳能转换效率，但这需要吸收光谱有强烈的红移，这会导致光异构体产生不希望的吸收以及热稳定性降低。这些化合物通常还具有较大的分子量，导致储能密度较低。相比之下，单取代体系在效率和储能密度之间实现了良好的折衷，同时避免了光异构体的竞争性吸收。这为分子太阳能热存储系统的未来发展确立了指导原则。
