Metal Ion-Directed Functional Metal–Phenolic Materials

Abstract

Metal ions are ubiquitous in nature and play significant roles in assembling functional materials in fields spanning chemistry, biology, and materials science. Metal–phenolic materials are assembled from phenolic components in the presence of metal ions through the formation of metal–organic complexes. Alkali, alkali-earth, transition, and noble metal ions as well as metalloids interacting with phenolic building blocks have been widely exploited to generate diverse hybrid materials. Despite extensive studies on the synthesis of metal–phenolic materials, a comprehensive summary of how metal ions guide the assembly of phenolic compounds is lacking. A fundamental understanding of the roles of metal ions in metal–phenolic materials engineering will facilitate the assembly of materials with specific and functional properties. In this review, we focus on the diversity and function of metal ions in metal–phenolic material engineering and emerging applications. Specifically, we discuss the range of underlying interactions, including (i) cation−π, (ii) coordination, (iii) redox, and (iv) dynamic covalent interactions, and highlight the wide range of material properties resulting from these interactions. Applications (e.g., biological, catalytic, and environmental) and perspectives of metal–phenolic materials are also highlighted.

Recent Advances in the Development and Antimicrobial Applications of Metal–Phenolic Networks

“…[21][22][23][24][25] And the organic components greatly expand the range of available substrates by modifying material shape or material substrate properties, modifying hydrophobicity, providing active reaction interfaces, contributing their specific physicochemical properties such as electrical or optical properties or acting as important components in some electrochemical or biochemical reactions. [23,26,27] MPNs, as amorphous networks, could be fabricated into various forms such as nanoparticles, hollow capsules, and hydrogels, and could be used as surface coating agents due to the high affinity providing by phenolic hydroxyl groups. [28][29][30][31][32][33][34][35] The coordinated self-assembly between phenolic ligands and metal ions exploiting the unique properties of polyphenols and metal ions has a wide range of applications in the biomedical fields.…”

“…[ 21–25 ] And the organic components greatly expand the range of available substrates by modifying material shape or material substrate properties, modifying hydrophobicity, providing active reaction interfaces, contributing their specific physicochemical properties such as electrical or optical properties or acting as important components in some electrochemical or biochemical reactions. [ 23,26,27 ]…”

Metal-phenolic networks as tuneable spore coat mimetics

“…The diversity of potential applications is tied to the ease of formation of MPNs, allowing for convenient and simple addition to a variety of substrates. [4][5][6][7] Specifically, there has recently been growing interest in the protection of beneficial microbes as both biotherapeutics and agricultural additives. 8,9 However, in many cases, non-model microbes remain challenging to produce at scale due to processing stresses.…”

“…The diversity of potential applications is tied to the ease of formation of MPNs, allowing for convenient and simple addition to a variety of substrates. 4–7…”

Robust and multifunctional natural polyphenolic composites for water remediation

“…Apart from the aforementioned MPNs derived from coordination interactions between metal ions and phenolic ligands, other kinds of interactions between metal ions and polyphenolic groups were also investigated. 30 For instance, the plentiful catechol/pyrogallol moieties of natural polyphenols have been characterized by high aromaticity and p-electron content, which could supply strong negative binding sites for cationic alkali or alkaline-earth metal ions to form cation-p interactions. 31 Noble metal ions (e.g., Ag + , Pd 2+ , and Au 3+ ) could be reduced into stable metallic forms by accepting electrons donated by polyphenols based on the redox reactions.…”