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Soft machines can offer remote-powering mechanisms and mechanical flexibility unmatched by conventional rigid machines. However, the molecular integration of powering and actuation functions in a simple yet versatile format has remained challenging. We achieve this with a semi-crystalline supramolecular metallo-network. The dynamic metallo-bonds offer a flexible mechanism for programming the network anisotropy, which gives rise to stress-free reversible actuation using the crystalline transition as the actuation phase. In addition, the proper choice of metallo-bonds provides suitable photo-thermal capabilities for remote powering without endangering the cyclic actuation stability, despite the supramolecular nature. Based on these principles, we illustrate that the supramolecular network can be programmed into a reptile-style device remotely powered by light. The molecularly integrated dual functionality based on supramolecular metallo-bonds provides an attractive option for the future design of soft machines with sophisticated morphing behaviors yet simple powering mechanisms.

Encoding molecular ordering during liquid crystalline network (LCN) formation endows preprogrammed but fixed shape morphing in response to external stimuli. The incorporation of dynamic covalent bonds enables shape reprogramming but also permanently alters the network structures. Here, an entropic approach that can program complex shapes via directed solvent evaporation from an isotropic LCN organo-gel is discoursed. Different shapes can be erased and reprogrammed from the same LCN on demand depending on the modes of deformation of the organo-gel during solvent evaporation. The ability to decouple network synthesis and molecular alignment relaxes the requirements to LCN chemistry and alignment methods, allowing for the realization of a variety of origami/kirigami structures and 4D shape morphing of LCNs printed from the digital light processing technique with unattainable spatial and temporal controls. This article is protected by copyright. All rights reserved.