Arylazopyrazoles for Long-Term Thermal Energy Storage and Optically Triggered Heat Release below 0 °C.
Arylazopyrazole derivatives based on four core structures (4pzMe, 3pzH, 4pzH, and 4pzH-F2) and functionalized with a dodecanoate group were demonstrated to store thermal energy in their metastable Z isomer liquid phase and release the energy by optically triggered crystallization at -30 °C for the first time. Three heat storage-release schemes were discovered involving different activation methods (optical, thermal, or combined) for generating liquid-state Z isomers capable of storing thermal energy. Visible light irradiation induced the selective crystallization of the liquid phase via Z-to-E isomerization, and the latent heat stored in the liquid Z isomers was preserved for longer than 2 …
Tuning Azoheteroarene Photoswitch Performance through Heteroaryl Design
International audience; Photoswitchable compounds, which can be reversibly switched between two isomers by light, continue to attract significant attention for a wide array of applications. Azoheteroarenes represent a relatively new but understudied type of photoswitch, where one of the aryl rings from the conventional azobenzene class has been replaced with a five-membered heteroaromatic ring. Initial studies have suggested the azoheteroarenes – the arylazopyrazoles in particular – to have excellent photoswitching properties (quantitative switching and long Z isomer half-life). Here we present a systematic computational and experimental study to elucidate the origin of the long thermal hal…
CCDC 1503532: Experimental Crystal Structure Determination
Related Article: Joaquín Calbo, Claire E. Weston, Andrew J. P. White, Henry S. Rzepa, Julia Contreras-García, Matthew J. Fuchter|2017|J.Am.Chem.Soc.|139|1261|doi:10.1021/jacs.6b11626
CCDC 1503530: Experimental Crystal Structure Determination
Related Article: Joaquín Calbo, Claire E. Weston, Andrew J. P. White, Henry S. Rzepa, Julia Contreras-García, Matthew J. Fuchter|2017|J.Am.Chem.Soc.|139|1261|doi:10.1021/jacs.6b11626
CCDC 1503531: Experimental Crystal Structure Determination
Related Article: Joaquín Calbo, Claire E. Weston, Andrew J. P. White, Henry S. Rzepa, Julia Contreras-García, Matthew J. Fuchter|2017|J.Am.Chem.Soc.|139|1261|doi:10.1021/jacs.6b11626