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Soft structures in nature, such as supercoiled DNA and proteins, can organize into complex hierarchical architectures through multiple noncovalent molecular interactions. Identifying new classes of natural building blocks capable of facilitating long-range hierarchical structuring has remained an elusive goal. We report the bottom-up synthesis of a hierarchical metal-phenolic mesocrystal where self-assembly proceeds on different length scales in a spatiotemporally controlled manner. Phenolic-based coordination complexes organize into supramolecular threads that assemble into tertiary nanoscale filaments, lastly packing into quaternary mesocrystals. The hierarchically ordered structures are preserved after thermal conversion into a metal-carbon hybrid framework and can impart outstanding performance to sodium ion batteries, which affords a capability of 72.5 milliampere hours per gram at an ultrahigh rate of 200 amperes per gram and a 90% capacity retention over 15,000 cycles at a current density of 5.0 amperes per gram. This hierarchical structuring of natural polyphenols is expected to find widespread applications.

Nanobiohybrids, synthesized by integrating functional nanomaterials with living systems, have emerged as an exciting branch of research at the interface of materials engineering and biological science. Nanobiohybrids use synthetic nanomaterials to impart organisms with emergent properties outside their scope of evolution. Consequently, they endow new or augmented properties that are either innate or exogenous, such as enhanced tolerance against stress, programmed metabolism and proliferation, artificial photosynthesis, or conductivity. Advances in new materials design and processing technologies made it possible to tailor the physicochemical properties of the nanomaterials coupled with the biological systems. To date, many different types of nanomaterials have been integrated with various biological systems from simple biomolecules to complex multicellular organisms. Here, we provide a critical overview of recent developments of nanobiohybrids that enable new or augmented biological functions that show promise in high-tech applications across many disciplines, including energy harvesting, biocatalysis, biosensing, medicine, and robotics., (Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).)

Multilayer thin films have garnered intense scientific interest due to their potential application in diverse fields such as catalysis, optics, energy, membranes, and biomedicine. Here we review the current technologies for multilayer thin-film deposition using layer-by-layer assembly, and we discuss the different properties and applications arising from the technologies. We highlight five distinct routes of assembly—immersive, spin, spray, electromagnetic, and fluidic assembly—each of which offers material and processing advantages for assembling layer-by-layer films. Each technology encompasses numerous innovations for automating and improving layering, which is important for research and industrial applications. Furthermore, we discuss how judicious choice of the assembly technology enables the engineering of thin films with tailor-made physicochemical properties, such as distinct-layer stratification, controlled roughness, and highly ordered packing., (Copyright © 2015, American Association for the Advancement of Science.)

The development of facile and versatile strategies for thin-film and particle engineering is of immense scientific interest. However, few methods can conformally coat substrates of different composition, size, shape, and structure. We report the one-step coating of various interfaces using coordination complexes of natural polyphenols and Fe(III) ions. Film formation is initiated by the adsorption of the polyphenol and directed by pH-dependent, multivalent coordination bonding. Aqueous deposition is performed on a range of planar as well as inorganic, organic, and biological particle templates, demonstrating an extremely rapid technique for producing structurally diverse, thin films and capsules that can disassemble. The ease, low cost, and scalability of the assembly process, combined with pH responsiveness and negligible cytotoxicity, makes these films potential candidates for biomedical and environmental applications.