Emission features, surface morphology and optical limiting properties of semiconducting Toluidine Blue O dye-poly(vinyl alcohol) nanocomposite architecture

Abstract

Fabrication of a new nanocomposite architecture comprising small weight percentage (< 0.5 wt%) of Toluidine Blue O dye as a filler in host polymer poly(vinyl alcohol) (PVA) via a simple route based on solution-casting is presented. Their microstructure, electrical, linear optical and third-order nonlinear optical properties are introduced here. These samples were characterized as nanocomposites, with dye chromophore uniformly distributed in the molecular chains of the polymer PVA. The effect of fluorescence quenching due to H-aggregates is also discussed. Low threshold third order nonlinear optical response of these nanocomposite film samples was carried out employing the Z-scan technique. With increase in intensity, a transition from reverse saturable absorption to saturable absorption was observed in the nanocomposite films, on excitation with continuous wave (CW) He-Ne laser light. The nonlinear refraction based optical limiting of CW laser light is demonstrated using aperture limited geometry. Compared with other reported results, the estimated values of the nonlinear refractive index (n 2), nonlinear absorption coefficients (β), third order nonlinear susceptibility (χ (3)) and limiting threshold are much better. These results thus possess tremendous scope towards future fabrication of optoelectronic and photonic devices such as organic/polymer light-emitting devices, dye-sensitized solar cells, optical limiters, optical switches, etc.

Td-DFT Study of Toluidine Blue O in Aqueous Solution: Vibronic Transitions and Electronic Properties

“…1) is a thiazine dye discovered by William Henry Perkin in 1856. TBO is widely used in photodynamic therapy of bacterial infections [1-8], for staining tissues and cells [9][10][11], as well as in biosensors (together with nanostructures) [12][13][14][15][16], solar cells [17] and semiconductor nanocomposites [18]. The therapy of Alzheimer's disease with TBO based on its inhibition of Tau protein aggregation is promising [19].…”

“…The therapy of Alzheimer's disease with TBO based on its inhibition of Tau protein aggregation is promising [19]. Using optical methods, it was found that the TBO molecule is able to effectively bind to DNA [20][21][22][23][24][25][26], RNA [26][27][28], proteins [19,[29][30][31][32][33][34], silver nanoparticles [6,35,36], silica [15] and cadmium sulfide [37], natural organic matter [38], cyclodextrins [39][40][41], surfactant micelles [40][41][42], chitosan [43], heparin [44], nanotubes [2], fatty acids [45] , polysaccharides [9,[46][47][48] and other polymers [18,49,50]. Numerous experimental optical studies of TBO itself have been carried outaggregation [21,[51][52][53][54], reduction [36,42,[55]…”

Linear and non linear optical properties of PVA-Ag/Coumarin Nanocomposites (again)

“…Fe, Al, Au, Cu, and Ag), oxides of metal (NiO, Al 2 O 3 , SiO 2 , PbO 2 , and Fe 2 O 3 ), different nanoparticles (e.g. NaI, CO, HgS, and NaI), semiconductors, carbon nanotubes, and magnetic nanoparticles have been utilized as an additive material in the polymer matrix to enhance its properties [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26]. Polyvinyl alcohol (PVA) is the most applicable host material for different nanoparticles with its unique physical features represented in high transmittance, non-corrosive nature, chemical resistance, thermostability, high mechanical strength, and easy processability, and high surface area [27][28][29][30].…”