Redox-active organic–inorganic hybrid polyoxometalate micelles

Abstract

(2017) Redox-active organic-inorganic hybrid polyoxometalate micelles.

Asymmetric Hybrid Polyoxometalates: A Platform for Multifunctional Redox‐Active Nanomaterials

“…Recently,w es howed that self-assembled micellar nanostructures formed from hybrid POM species exhibit different redox properties to their constituent molecular species. [29,35] CV experiments were conducted on 1 dissolved in a0 .1m H 2 SO 4 :CH 3 CN (9:1, v/v) mixture,a llowing for spontaneous assembly into micellar species as described above.Here,j ust two redox processes were observed between À0.5 and 0.5 V (vs.A g/AgCl) in contrast to the three seen in pure DMF (Supporting Information, Figure S15), as appears typical of micellar species of this type. [29,35] Notably,c haracteristic molecular redox behavior can be rapidly recovered by addition of DMF to the electrolyte solution, indicating the dynamic nature of this system and offering interesting potential for the development of responsive or switchable electrochemical devices.T his behavior also corresponds closely to that seen for our previously reported symmetric surfactant hybrid system, [35] and for the symmetric product 3 (Supporting Information, Figure S21).…”

“…[19] Notably,h owever, this requires demanding,e xpensive,a nd time-consuming methods (such as chromatography or slow fractional crystallization) followed by multiple synthetic steps to obtain the asymmetric product. [20][21][22] Reported examples of asymmetric hybrid POMs that exhibit complex functionalities are even fewer, [21,23] and (with the notable exception of aseries of elegant though hydrolytically unstable organotin hybrid POMs reported by Lacôte,T horimbert, and Hasenknopf) [24] are limited to the Mn-Anderson cluster type,which displays limited photo-and redox-activity compared to many POMs.C onversely,a dvanced functionalization strategies targeting clusters such as the Wells-Dawson anion, with its rich redox activity and highly tunable organic hybrid structures, [25][26][27] will provide new pathways for the isolation of advanced, multi-functional soft-nanostructures [28,29] and metal-directed extended assemblies. [30,31] Ultimately,t his could allow for the design of materials with switchable morphologies and functions in arange of different media, leading to new applications in catalysis,drug-delivery systems,orencapsulated nano-reactors.…”

“…Functionalization of polyoxotungstates with aryl phosphonate groups enhances their photochemical properties and can be employed to direct their self-assembly into micellar superstructures. [29,[34][35][36] Here,w ea imed to introduce two distinct, orthogonal functionalities via asymmetric functionalization and designed two suitable aryl phosphonates accordingly:( PO 3 C 21 H 16 N 3 )( TPY), at erpyridine-based ligand, and (PO 4 C 24 H 43 )( C 18 ), an aliphatic chain group (see the Supporting Information). Hybridization was then conducted based on the previously reported method.…”

Electroactive Amphiphiles for Addressable Supramolecular Nanostructures

“…The self‐assembly of these EAAs allows for the preparation of well‐defined structures, with properties that are often enhanced owing to the macroscopic order of the material. A wide range of such EAAs have been investigated, from small molecules such as anthraquinone and POMs,, to oligomers and polymers ,…”

Redox‐Active Hybrid Polyoxometalate‐Stabilised Gold Nanoparticles

“…(1), [14] and report a detailed comparison of the new Au@hybrid-POM nanoparticle composite NP-1 with its electrostatically stabilised analogue NP-P 2 W 18 , comprising AuNPs noncovalently capped with the conventional K 6 [P 2 W 18 O 62 ] ({P 2 W 18 }) Wells-Dawson cluster (Scheme 1). [15] Transmission electron microscopy (TEM), Xray photoelectron spectroscopy (XPS), and X-ray absorption near-edge structure (XANES), UV/Visible absorption, and FT-IR analyses have been used to probe the structure and surface interactions of both nanoparticle composites, whilst spectroscopic and voltammetric analyses have been used to compare their photo-and electrochemical properties, respectively.…”