Substrate‐Bound Diarylethene‐Based Anisotropic Metal–Organic Framework Films as Photoactuators with a Directed Response

Abstract

AbstractMolecular machines and responsive materials open a plethora of new opportunities in nanotechnology. We present an oriented crystalline array of diarylethene (DAE)‐based photoactuators, arranged in a way to yield an anisotropic response. The DAE units are assembled, together with a secondary linker, into a monolithic surface‐mounted metal–organic framework (SURMOF) film. By Infrared (IR) and UV/Vis spectroscopy as well as by synchrotron X‐ray diffraction, we show that the light‐induced extension changes of the molecular DAE linkers multiply to yield mesoscopic and anisotropic length changes. Due to the special architecture and substrate‐bonding of the SURMOF, these length changes are transferred to the macroscopic scale, leading to the bending of a cantilever and performing work. This research shows the potential of assembling light‐powered molecules into SURMOFs to yield photoactuators with a directed response, presenting a path to advanced actuators.