A General Bioinspired, Metals-Based Synergic Cross-Linking Strategy toward Mechanically Enhanced Materials

Abstract

Creating lightweight engineering materials combining high strength and great toughness remains a significant challenge. Despite possessing-enhanced strength and stiffness, bioinspired/polymeric materials usually suffer from clearly reduced extensibility and toughness when compared to corresponding bulk polymer materials. Herein, inspired by tiny amounts of various inorganic impurities for mechanical improvement in natural materials, we present a versatile and effective metal ion (M)-based synergic cross-linking (MSC) strategy incorporating eight types of metal ions into material bulks that can drastically enhance the tensile strength (∼24.1-70.8%), toughness (∼18.6-110.1%), modulus (∼21.6-66.7%), and hardness (∼6.4-176.5%) of multiple types of pristine materials (from hydrophilic to hydrophobic and from unary to binary). More importantly, we also explore the primarily elastic-plastic deformation mechanism and brittle fracture behavior (indentation strain of >5%) of the synergic cross-linked graphene oxide (Syn-GO) paper by means of in situ nanoindentation SEM. The MSC strategy for mechanically enhanced integration can be readily attributed to the formation of the complicated metals-based cross-linking/complex networks in the interfaces and intermolecules between functional groups of materials and various metal ions that give rise to efficient energy dissipation. This work suggests a promising MSC strategy for designing advanced materials with outstanding mechanical properties by adding low amounts (<1.0 wt %) of synergic metal ions serving as synergic ion-bonding cross-linkers.

Coordination‐Driven Hierarchical Assembly of Hybrid Nanostructures Based on 2D Materials

“…Besides the ligand, another requirement for the coordination reaction is the coordination center, which are usually metal ions that contain unoccupied orbitals. Various metal ions have been explored for the coordination‐driven assembly of graphene‐based hybrid nanostructures, including Ca 2+ , Mg 2+ , Cu 2+ , Zn 2+ , Co 2+ , Ni 2+ , Cd 2+ , Fe 2+ , Fe 3+ , Mn 2+ , Cr 2+ , Al 3+ , La 3+ , Bi 3+ , Y 3+ , Ag + , etc . During this assembly, metal ions can be either added from a foreign source (e.g., salts) or provided by another building block that already involves a coordination center.…”

“…These divalent cations could coordinate not only with the oxygen‐containing functional groups on the basal planes of GO nanosheets, but also the carboxylic groups on the edges. Subsequently, various cations were used to modify the GO paper, including divalent and trivalent metal ions, and complex cations (e.g., ZrO 2+ and TiO 2+ ) . Due to the strong coordination interaction between GO nanosheets, the cation‐coordinated GO (GO‐M x + ) papers showed not only significantly reinforced mechanical properties (Figure b), but also impressively enhanced properties in thermal transfer, electrical conductivity, and stability (Figure c) .…”

Nacre‐Inspired Structural Composites: Performance‐Enhancement Strategy and Perspective

“…[38,39] Guo and co-workers [39] have systematically studied the influence of different metal ions (eight kinds, such as Mg 2+ , Ni 2+ , Ca 2+ , Cu 2+ , Co 2+ , ZrO 2+ , TiO 2+ /(TiO) n 2n+ , and Al 3+ ) when introduced into the binary system and the synergic ion-bonding crosslinking between interfaces was confirmed (Figure 1k-o). Different metal ions would result in different mechanical performances, due to the differences in sizes and charges.…”

Ice-Templated W-Cu Composites with High Anisotropy

“…The large melting point fabrication requires high temperature annealing making the design of new materials extremely challenging. Of particular interest is the assembly of functional composites with anisotropic phase orientations [13][14][15][16][17][18] which would allow for a highly directional materials response, e.g. anisotropic thermal or electrical conductivity.…”