Incorporating polymers within a single‐crystal: From heterogeneous structure to multiple functions

Abstract

Single-crystals, commonly considered as homogeneous solids, are able to be internally interfaced abnormally with guest polymers, which can be found in the biominerals where single-crystals incorporate surrounding biomacromolecules to reinforce their mechanical properties. This unique feature combining heterogeneous structure and long-range atomic ordering have attracted abundant investigations of reproducing their synthetic analogs to expand the potential application scope. Here, we summarize the recent progresses in the synthetic single-crystal composites, where polymer guests are incorporated inside single-crystals to generate heterogeneous structures without interruption to the long-range ordering of crystal hosts. First, the uniform and patterned encapsulations inside the various single-crystals are concluded in the sequence of isolated and continuous polymer-based guests. In addition, the mechanisms are classified chemically and physically, and the corresponding controlled factors that govern the incorporation processes are discussed. Most importantly, typical attempts on the applications of these heterogeneous single crystals are introduced, including mechanical reinforcement, bandgap engineering, catalyst, self-healing, controlled release, and optoelectronic devices.We aim at stressing on the current and potential applications benefited from the unique structural properties of the polymer incorporated single-crystals, and accordingly propose the perspectives to accelerate the path from the structural analysis toward prosperous functions.

Occlusion of Diblock Copolymer-Modified Gold Nanoparticles Generates Diabolo-Shaped Au@ZnO Nanocomposite Crystals with Enhanced Photocatalytic Properties

“…Moreover, Li et al demonstrated that incorporation of conjugated polymer networks into C 60 single crystals can enhance their optoelectronic properties and incorporation of TiO 2 networks into PbI 2 crystals can improve X-ray detection sensitivity . In recent years, various amphiphilic diblock copolymer nanoparticles have been employed as crystal growth additives: this approach has produced a wide range of nanocomposite materials in which the guest organic nanoparticles are densely occluded within host inorganic crystals. − Prior to these studies, Wegner et al pioneered the use of polymeric latexes as particulate additives for the mineralization of ZnO, demonstrating the successful incorporation of such particles . Similar results have been achieved using polymer-stabilized inorganic nanoparticles and even copolymer-stabilized oil droplets for other host crystals. − It is remarkable that a wide range of hybrid materials can be designed using such a straightforward, efficient method. − Unlike diblock copolymer nanoparticles, double-hydrophilic diblock copolymers are molecularly dissolved in aqueous solution.…”

Isotropically Dyed Single Crystals Produced via Gel-Incorporation

“…To construct a uniform occlusion of dyes within an NLO single-crystal, instead of the anisotropic incorporation, an isotropic binding interaction that induces the incorporation process needs to be introduced into the crystallization condition. Interestingly, nonspecific binding interactions widely exist in the crystallization process within gel matrices. − This is also inspired by the biomineralization process where the growing mineral crystals incorporate surrounding biomacromolecules. − As a single crystal growing in a gel matrix, the interconnected gel-networks can withstand the crystallization pressure exerted from growing surfaces, leading to gel-incorporation and three-dimensional penetration of gel-networks throughout the entire single crystal . More importantly, nanoparticles , and microgels that are essentially incompatible with single crystals could be efficiently incorporated under the guidance of gel-networks.…”

“…In combination with the gel-incorporation triggered isotropic dyeing structure, as well as the boosted dye contents inside the crystals, the dyeing mechanisms of a gel-grown KDP single crystal can be proposed. First, silica hydrogels have three-dimensionally irregular gel-networks with high specific surface area, which are full of hydroxyl groups. , Therefore, a large quantity of free dye molecules in the gel matrix are able to bind on the gel-networks by virtue of physical absorption or H-bonds, as evidenced by the PL quenching of dyes observed in gels. Second, when crystallization starts, the growing crystals isotropically incorporate the surrounding interconnected and dye-attached gel-networks, ensuring the isotropic dyeing of crystals.…”

Metal–Organic Frameworks@Calcite Composite Crystals

“…Although various nanoparticles have been encapsulated into MOFs, it remains a technical challenge to efficiently incorporate MOF crystals into inorganic single crystals during the crystallization of the latter in aqueous media. This is perhaps not surprising because crystallization normally favors the exclusion of impurities rather than their inclusion. − In the present study, we sought to incorporate MOF nanoparticles into inorganic host crystals (CaCO 3 ). Our strategy involves the decoration of the MOF crystals with a suitable polymer to not only overcome the incompatibility between the guest MOF crystals and the host crystals, but also drive the efficient incorporation of MOF crystals into host crystals (Scheme ).…”