Search

Transient structures play a wide range of vital roles in biological systems. Different from static structures that form the skeleton of bio‐tissues, transient structures only occur at certain spatial and temporal scales to undertake their duties in the life circle. Despite the significant progress in the field of artificial molecular self‐assembly studies, it still remains challenging to construct functional transient structures. Herein, the shaping of transient coordinating self‐assembled structures and their fluorescence is reported via host‐guest interaction that disfavors the assembly. The host‐guest interaction between the luminescent ligand and cyclodextrin drastically changes the kinetics of the coordinating self‐assembly, enabling the formation of transient structures. Different from the static equilibrium one with typical monomer emission in the UV region, the transient self‐assembly forms excimers, leading to visible emission. More intriguingly, the life cycle of the transient structures can be easily modulated by varying the host‐guest ratio, ligand‐metal ratio, as well as temperature. This makes it possible to create living patterns that mimic the growth of plants at different life stages. It is therefore envisioned that the creation of transient molecular self‐assembly will open a new paradigm in the field of molecular self‐assembly featuring advanced materials with dynamic functions. [ABSTRACT FROM AUTHOR]

Abstract: Caking of powder materials is undesired in various industries, and for thousands of years people are fighting against caking. Herein, the principle of caking is employed to create macroscopic plastic supramolecular films through a cold sintering process. A nanometer‐sized, irregular coordinating cluster is first generated with a bulky head surfactant and multifunctional ligand, and the addition of metal ions immediately leads to amorphous white precipitates. Upon adsorbing moisture, a rearrangement of the molecules in the precipitates results in cold sintering, so that the particles in the precipitates grow into a transparent macroscopic film. The mechanical strength of the film is comparable to plastics, but allows welding and molding with finger at ambient temperature in moist environment. Mechanical tests suggest the supramolecular plastic does not fatigue even after several tens circles' remolding, indicating their superior material engineering capability. This strategy can be extended to different chemistries to fabricate films with different mechanical strength. Various functional components can be doped into the resultant films, rendering them a platform toward multifunctional materials, such as luminescent devices or sensors for pollution gases. The current strategy opens up a new vista in material science is expected. [ABSTRACT FROM AUTHOR]