Polymer‐Coated PtCo Nanoparticles Deposited on Diblock Copolymer Templates: Chemical Selectivity versus Topographical Effects

Abstract

Metal-polymer hybrid films are prepared by deposition of polymer-coated PtCo nanoparticles onto block copolymer templates. For templating, a thin film of the lamella-forming diblock copolymer poly(styrene-b-methyl methacrylate) P(S-b-MMA) is chemically etched and a topographical surface relief with 3 nm height difference is created. Two types of polymer-grafted PtCo nanoparticles are compared to explore the impact of chemical selectivity versus the topographical effect of the nanotemplate. A preferable wetting of the polystyrene (PS) domains with poly(styrenesulfonate) (PSS)-coated PtCo nanoparticles (instead of residing in the space between the domains) is observed. Our investigation reveals that the interaction between PSS-coated nanoparticles and PS domains dominates over the topographical effects of the polymer surface. In contrast, a non-selective deposition of poly(N-vinyl-2-pyrrolidone) (PVP)-coated PtCo nanoparticles and the formation of large metal-particle aggregates on the film is observed.

Conductivity and Morphology Correlations of Ionic-Liquid/Lithium-Salt/Block Copolymer Nanostructured Hybrid Electrolytes

“…Also cross-linked PEMs based on PEO for LIB or Li–S batteries attract more and more interest in research due to their high ionic conductivity upon high mechanical stability. ,, Generally, block copolymers (BCs) have two or more chemically different polymer blocks linked via covalent bonds. The BCs undergo a microphase separation and self-assembly processes and thereby create various nanoscale morphologies, such as spheres, cylinders, gyroids, or lamella. − The lithium-ion doping in PEO-based BCs has been mainly investigated as a potential solid-state membrane because the conductive PEO block has the ability to solvate lithium ions. The PEO is combined with glassy blocks such as polystyrene (PS) to achieve a high modulus, and thereby the necessary mechanical stability of the PEMs. − ,,, In the bulk as well as in films, the doping with lithium ions showed a significant effect on both the structure and the conductivity of PEO-based BCs. , Ionic conductive PS- b -PEO BCs were reported for a certain lithium-ion concentration threshold ([Li]/[EO] = 0.1, mole ratio) with an enhanced mechanical stability. ,, At much higher salt concentrations, aggregates of lithium salt and a limited conductivity performance were observed .…”

Patterned Diblock Co-Polymer Thin Films as Templates for Advanced Anisotropic Metal Nanostructures

“…The tailoring of metal nanoparticles layers and hybrid materials plays a crucial role in modern advanced material science. − The demand ranges from hydrophobic surfaces and flexible sensors , to organic photovoltaics (OPV) , and magnetic storage media . The related objective is to combine the tunable nanostructure of diblock copolymeric materials , with the selective interaction of metals with different polymer materials. − …”

Arrangement of Maghemite Nanoparticles via Wet Chemical Self-Assembly in PS-b-PNIPAM Diblock Copolymer Films

“…Particularly interesting are wet chemical approaches, which use ink-type mixtures of NPs and DBC, because such approaches would allow for large scale fabrication methods such as printing or spray coating . A prerequisite for such an approach is the use of functionalized NPs to promote a preferential affinity to one of the DBC blocks . Properly functionalized NPs exhibit an enthalpic driving force for the selective deposition of the NPs inside one domain of the microphase separated structure during the self-assembly process of the NPs/DBC mixture. , Moreover, such proper coating of the NPs can prohibit self-aggregation of the NPs in the polymer phase to some extent .…”