Creation of Highly Ordered “Nano-Mille-Feuille” Hard/Soft Nanoparticle Multilayers with Interparticle Cross-Linking by Diacetylene-Containing Chains

Abstract

In this study, we attempted to create a precise nanostructure in which hard and soft layers were alternately stacked with a period of 5 nm. Such a periodically stacked structure can be used as a model material to elucidate the origin of the innovative mechanical property improvement proposed for Mg alloy systems. The soft layer was a single layer of nanoparticles made of a ternary copolymer containing a carbazole ring and both hydrocarbon and fluorocarbon chains. The hard layer was a single-particle layer made of magnetite nanoparticles; the surface of these particles was modified with long-chain diynoic acid. The multilayers of each single-particle layer were 54% crystalline and ordered with a D 001 crystallite size of approximately 20 nm. The nano-mille-feuille structure, in which the hard and soft layers are repeated in a single-digit nanoperiod, was 56% crystalline and ordered with a D 001 crystallite size of approximately 15 nm. Infrared absorption spectroscopy and X-ray photoelectron spectroscopy did not show any loss of both hard and soft layers. Even when the thickness/number of layers was changed variously, no remarkable decrease was observed in the order. Cross-linking between particles by ultraviolet irradiation polymerization was performed for the direct evaluation of the mechanical properties of this structure in the future. Even after topochemical polymerization between the modified chains, the order of the particle stacking structure was maintained.

Regularity Maintenance Properties under Deformation of Kink-Introduced Nano-Mille-Feuille Structures Derived from Interfacial Friction

“…The former showed 74% crystallinity, with a D 001 microcrystal size of 187 Å, while the latter exhibited 68% crystallinity with a D 001 microcrystal size of 132 Å. Similar to the multiparticle layers on the glass substrate in previous studies, , the same degree of regularity was ensured between the layered single-particle film and the Nano-mille-feuille. Therefore, it has been proven that an orderly multiparticle film can be produced because this method of the layered single-particle film is regardless of organic/inorganic constituents.…”

“…In addition, on the side with many layers, the maintenance of order in 40 layers, which is double the amount, is evaluated. Furthermore, it has already reported the regularity maintaining shown in the previous papers , when the periodicity of alternating layering is changed.…”

“…The surface pressure–area isotherms (15 °C) of the single-particle layer of the polystyrene nanoparticles and organo-modified Fe 3 O 4 shown in the previous reports , and the formation mechanism thereof are shown (Figure S1 in the Supporting Information). Since polystyrene is a hydrophobic polymer without hydrophilic groups, the polymer chains are folded so that they are stacked in the height direction to reduce the contact area with water at the air/water interface.…”

“…In recent years, organic/inorganic layered nanohybrids known as “Nano-mille-feuilles” with high regularity have been produced , (Figure , lower) by alternately layering a polymer nanosphere monolayer (a polymer fine particle film) and an organo-modified inorganic nanoparticle monolayer . These multinanoparticle layers were created by spreading them at the air/water interface using the Langmuir monolayer and Langmuir–Blodgett (LB) films. − In these materials, precise structural evaluation was performed using paracrystal analysis, which utilizes thin-film X-ray diffraction (XRD).…”

Nanofabrication Techniques in Large-Area Molecular Electronic Devices

“…In addition to the typical amphiphilic molecules described above, the LB technique is largely enlarged towards the assembly of more complex structures with interest in molecular electronics (and organic electronics). Polymers [281][282][283], metalloporphyrines [284], DNA [285], perylenes [286], perylene-NH 2 [287], ruthenium complexes [288], organo-modified inorganic nanoparticles in combination with polymer nanospheres (nano-mille-feuille system) [289], pillar [5]arene derivatives [290], polymer-coated CsPbBr 3 nanowires [291], aligned SWCNTs [145], semi-conductive 2D materials based on 2,3,6,7,10,11-hexaiminotriphenylene (HATP) [292], or rGO [146] have been used.…”