Surfactant-Encapsulated Clusters (SECs): (DODA)20(NH4)[H3Mo57V6(NO)6O183(H2O)18], a Case Study

Abstract

We present a comprehensive study of the partially reduced polyoxomolybdate [H 3 Mo 57 V 6 (NO) 6 (2) was isolated as a dark violet solid, which readily dissolves in organic solvents. Slow evaporation of solutions of 2 on solid substrates forces the hydrophobic particles to aggregate into a cubic lattice. Annealing these so-formed films at elevated temperature causes de-wetting with terrace formation similar to liquid crystals and block copolymers. Compound 2 forms a stable Langmuir monolayer at the air ± water interface; Langmuir ± Blodgett multilayers are readily prepared by repeated transfer of monolayers on solid substrates. The films were characterized by optical ellipsometry, Brewster angle microscopy, transmission electron microscopy, and X-ray reflectance.

Construction of Amphiphilic Polyoxometalate Mesostructures as a Highly Efficient Desulfurization Catalyst

“…In this perspective, mostly double-chain surfactant molecules have been applied, and a variety of structures have been found by exploiting noncovalent interactions between the amphiphilic units. [31][32][33][34][35][36][37] A1 spontaneously selfassembles and forms semitubular structures in the butanone/ per-POM, [ 19 , 28 ] which subsequently easily escape because of their relatively strong polarity. Thus, hydrophobic alkyl chains act as a trap for sulfi de molecules and as a result enhance the catalytic effi ciency of the amphiphilic POM compared to bare POM.…”

Organized Nanostructured Complexes of Polyoxometalates and Surfactants that Exhibit Photoluminescence and Electrochromism

“…[16][17][18] Functional superlattice Langmuir-Blodgett (LB) films were fabricated by taking advantage of the adsorption properties of the POM along a positively charged organic monolayer spread on water. [19][20][21][22] Kurth et al [23][24][25][26] exchanged the POM counterions with (dimethyldioctadecylammonium) DODA to alter the surface chemical properties of POMs, yielding discrete hydrophobic ''surfactant-encapsulated clusters'' (SECs). Following this, the structure of Langmuir and LB films of SECs, and various functional assemblies based on SECs were investigated.…”

Metallo-supramolecular modules as a paradigm for materials science

“…This preparation scheme permits the characterization of the materials used in each step. This approach has also been successfully used to encapsulate POMs with dendritically branching amphiphiles [141][142][143][144]. These results show that surfactant encapsulation is widely applicable to different POM clusters and amphiphilic systems.…”