School of Chemistry, The University of Sydney, Sydney, NSW, 2006, Australia.
Sydney Analytical, Core Research Facilities, The University of Sydney, Sydney, NSW, 2006, Australia.
Nat Commun. 2020 Jun 4;11(1):2808. doi: 10.1038/s41467-020-15510-7.
Reversible structural transformations of porous coordination frameworks in response to external stimuli such as light, electrical potential, guest inclusion or pressure, amongst others, have been the subject of intense interest for applications in sensing, switching and molecular separations. Here we report a coordination framework based on an electroactive tetrathiafulvalene exhibiting a reversible single crystal-to-single crystal double [2 + 2] photocyclisation, leading to profound differences in the electrochemical, optical and mechanical properties of the material upon light irradiation. Electrochemical and in situ spectroelectrochemical measurements, in combination with in situ light-irradiated Raman spectroscopy and atomic force microscopy, revealed the variable mechanical properties of the framework that were supported using Density Functional Theory calculations. The reversible structural transformation points towards a plethora of potential applications for coordination frameworks in photo-mechanical and photoelectrochemical devices, such as light-driven actuators and photo-valves for targeted drug delivery.
多孔配位框架在光、电势、客体包合或压力等外部刺激下的可逆结构转变，一直是传感、开关和分子分离等应用领域的研究热点。在这里，我们报道了一种基于四硫富瓦烯的配位框架，它表现出可逆的单晶到单晶的双[2+2]光环化反应，导致材料在光照下电化学、光学和力学性能发生显著变化。电化学和原位光谱电化学测量，结合原位光照拉曼光谱和原子力显微镜，揭示了框架的可变力学性能，并用密度泛函理论计算进行了支持。这种可逆的结构转变表明，配位框架在光机械和光电化学器件中具有广泛的潜在应用，如光致动器和用于靶向药物输送的光阀。
