The self-assembly of molecular building blocks into well-defined macroscopic materials is desirable for developing emergent functional materials. However, the selfassembly of molecules into macroscopic materials remains challenging, in part because of limitations in controlling the growth and robustness of the materials. Herein, we report the molecular self-assembly of nano-to macroscopic free-standing materials through the coordination of metals with natural phenolic molecules. Our method involves a simple and scalable solution-based template dipping process in precomplexed metal−phenolic solutions, enabling the fabrication of free-standing macroscopic materials of customized architectures (2D and 3D geometries), thickness (about 10 nm to 5 μm), and chemical composition (different metals and phenolic ligands). Our macroscopic free-standing materials can be physically folded and unfolded like origami, yet are selectively degradable. Furthermore, metal nanoparticles can be grown in the macroscopic free-standing films, indicating their potential for future applications in biotechnology and catalysis.
Metalphenolic networks (MPNs) are an emerging class of functional metal-organic materials with a high degree of modularity in terms of the choice of metal ion, phenolic ligand, and assembly method. Although various applications, including drug delivery, imaging, and catalysis, have been studied with MPNs, in the form of films and capsules, the influence of metals and organic building blocks on their mechanical properties is poorly understood. Herein, we demonstrate that the 2 mechanical properties of MPNs can be tuned through choice of the metal ion and/or phenolic ligand. Specifically, the pH of the metal ion solution and/or size of phenolic ligand influence the Young's modulus (EY) of MPNs (higher pHs and smaller ligands lead to higher EY). This study systematically investigates the roles of both metal ions and ligands on the mechanical properties of metal-organic materials and lends new insight into engineering the mechanical properties of coordinated films.
The role of interfacial coatings in gas transport dynamics in foam coarsening is often difficult to quantify. The complexity of foam coarsening measurements or gas transport measurements between a bubble and air-water interface requires assumptions about the liquid thin film thickness profile in order to explore the effects of interfacial coatings on gas transport. It should be possible to independently quantify the effects from changes in film thickness and interfacial permeability by using both atomic force microscopy and optical microscopy to obtain time snapshots of this dynamic process. Experiments We measure the mass transfer between the same nitrogen microbubbles pairs in an aqueous solution using two methods simultaneously. First, we quantify the bubble volume changes with time via microscopy and second, we use Atomic Force Microscopy to measure the film thickness and mass transfer resistances using a model for the gas transport. Findings Modelling of the interface deformation, surface forces and mass transfer across the thin film agrees with independent measurements of changes in bubble size. We demonstrate that an anionic surfactant does not provide a barrier to mass transfer, but does enhance mass transfer above the critical micelle concentration. In contrast, a polymer monolayer at the interface does restrict mass transfer.
This study reports on the ultrasonic processing of pea protein isolate (PPI) in phosphate-buffered saline (PBS, pH 7.4) and Tris/HCl (pH 8) buffer systems in order to modify its properties for use in the encapsulation of functional liquids.
Microencapsulation of liquid solvents is a promising approach to utilizing viscous, corrosive, or kinetically limited solvents for large-scale gas separations in a practical manner. A major drawback of the technology is the difficulty of manufacturing capsules on an industrial scale. In this article, an alternative means of immobilizing liquid solvents inside high-surface-area polymers is proposed. A gel material containing ∼50 wt % solvent embedded inside a continuous polymer matrix is formed by a scalable one-pot method. The material may be shaped into thin films or particles with surface areas comparable to microcapsules, and gels containing concentrated K 2 CO 3 solutions were stable through multiple cycles of gas absorption/regeneration and hydration/dehydration. Mass transfer measurements were in good agreement with a theoretical model, which predicted that, for concentrated solvents inside gels of appropriate thickness, the high permeability of the polymer can increase the gas f lux into the material relative to a neat solvent.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.