Optical properties of polyelectrolyte quantum dot multilayer films prepared using the layer by layer self-assembly method

We introduce a novel and versatile approach for controlling anti-reflective (AR) properties of multilayer films based on layer-by-layer (LbL) self-assembly (SA) method. For the fabrication of these films, blend (i.e., mixed) layers containing both polyanions (i.e., titanium precursor (TALH) and poly(sodium 4-styrenesulfonate) (PSS)) were assembled with polycation (i.e., poly(diallyldimethylammonium chloride) (PDAD)) for the formation of the high refractive index multilayers and on the other hand, the negatively charged silica particles with the diameter of about 100 nm were employed for low refractive index layer. The refractive index of TALH:PSS/PDAD multilayer was controlled by blending ratio and annealing temperature as TALH has the relatively high refractive index (n = 1.68) in comparison with that (n = 1.46) of conventional polyelectrolytes (PEs) at room temperature and furthermore these titanium precursors are partially changed into TiO2 with relatively high refractive indices (n = 1.50 ~ 1.81) at annealing temperature of 250 oC. In the case of silica particle layer used for low refractive index layer, the calculated refractive index was about 1.35 due to much vacancy among the adsorbed silica colloids although the inherent refractive index of silica material is about 1.45. As a result, the films composed of TALH:PSS/PDAD multilayers with tunable refractive index and silica colloidal layer can easily modulate the optical properties of multilayer films by blending ratio and heat treatment.

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Hydrogen-Bonding Layer Protecting Polyelectrolyte Capsules and Its Mechanical Property Study with Atomic Force Microscope

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2008.156 ◽

2008 ◽

Vol 8 (6) ◽

pp. 2996-3002 ◽

Cited By ~ 4

Author(s):

Liqin Ge ◽

Xing Wang ◽

Long Ba ◽

Zhongze Gu

Keyword(s):

Hydrogen Bonding ◽

Atomic Force Microscope ◽

Elastic Deformation ◽

Self Assembly ◽

Laser Scanning ◽

Confocal Laser ◽

Bonding Layer ◽

Layer By Layer ◽

Assembly Method ◽

Atomic Force

The hydrogen-bonding multilayered polyelectrolyte capsules with sizes around 6 μm were fabricated by layer-by-layer self-assembly method. The morphology of the obtained capsules was observed with Scanning Electron Microscope (SEM), Confocal Laser Scanning Microscope (CLSM) and Atomic Force Microscope (AFM), respectively. The elastic properties of the capsules were studied with AFM. The capsule was pressed by cantilever with different lengths, a glass bead glued at the end of the cantilever. The force curves were measured on the capsule in air. The Young's modulus of the capsule was obtained (E = 170 MPa for the loading). Results show that this model can predict the elastic deformation of the microcapsule. The accuracy of the elastic deformation of polymer capsule can be ensured using a cantilever of mediate stiffness. Our results show that the existence of the hydrogen-bonding layer makes the multilayered polyelectrolyte harder in comparison with the pure multilayered polyelectrolyte capsules.

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Fabrication of montmorillonite and titanate nanotube based coatings via layer-by-layer self-assembly method to enhance the thermal stability, flame retardancy and ultraviolet protection of polyethylene terephthalate (PET) fabric

RSC Advances ◽

10.1039/c6ra05213d ◽

2016 ◽

Vol 6 (59) ◽

pp. 53625-53634 ◽

Cited By ~ 15

Author(s):

Ying Pan ◽

Wei Wang ◽

Haifeng Pan ◽

Jing Zhan ◽

Yuan Hu

Keyword(s):

Thermal Stability ◽

Polyethylene Terephthalate ◽

Flame Retardancy ◽

Self Assembly ◽

Layer By Layer ◽

Pet Fabric ◽

Thermal Oxidative Stability ◽

Titanate Nanotube ◽

Assembly Method ◽

Ultraviolet Protection

Montmorillonite and titanate nanotube based coatings have been prepared through LbL self-assembly method, in order to enhance the thermal and thermal-oxidative stability, flame retardancy and UV protection of polyethylene terephthalate fabric.

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