The Au shell not only improves the chemical stability of Ag NPs but also increases the index sensitivity at an optimum thickness. Laser-generated Ag-Au NPs with Au shell of 1–2 nm show optimum RIS and FOM in lower-wavelength Ag plasmon channel. A sequential laser ablation method is used to generate bimetallic Ag-Au and Ag-Cu core-shell NPs in liquid medium, and their LSPR peak shift and broadening are monitored in different refractive index liquids. Bimetallic Ag-Au and Ag-Cu core-shell NPs exhibit two resonance peaks, corresponding to hybridization of core and nanoshell plasmon modes, are investigated for simultaneous sensing in two widely separated wavelength regions. The simulation results reveal that RIS and FOM of Ag NPs are higher than Au and Cu NPs. Refractive index sensitivity (RIS) and figure-of-merit (FOM) of Ag, Au, and Cu are analyzed for different particle sizes using the quasi-static Mie theory. Localized surface plasmon resonance (LSPR) wavelength of Ag, Au, and Cu nanoparticles (NPs) falls in visible region and is highly sensitive to size, shape, and surrounding medium. The melting response of alumina (Al2O3), aluminium and silver nanoparticles with 532-nm laser wavelength provides novel pathway for rattle-type formation. The morphology and chemical composition of the nanostructures were characterized by transmission electron micrograph, high-resolution transmission electron micrograph and energy-dispersive X-ray analysis. At longer irradiation time, the Kirkendall effect becomes dominant due to diffusion rate mismatch between the two metals at the interface and facilitates the formation of porous alumina shell over silver core. The transmission electron micrographs revealed morphological changes from sintered-/intermediate-type structure in water medium and jointed structure (heterostructures) in polymer solution to rattle-type structure with changing irradiation time. Silver and aluminium nanoparticles were prepared by pulsed laser ablation in liquid using same laser wavelength. The temperature dependencies of the spontaneous polarization and switching time for new binary mixture and its components were compared and analyzed in terms for possible applications.Ī simple and flexible method has been presented for the fabrication of rattle-type nanostructures in water and polyvinyl pyrrolidone polymer solution based on laser-induced heating of mixture of silver (Ag) and aluminium (Al) nanoparticles by 532-nm laser. Additionally, the molecular reorientation around the short axis was recognized in the monotropic hexatic phase. Dielectric spectroscopy has shown the strong low frequency relaxation process in the SmC* identified as related to Goldstone mode based on the mean–field model. Moreover, the calorimetric, texture observations as well as dielectric studies revealed an additional monotropic liquid crystalline phase for one of the mixture component, which was identified, based on X–ray diffraction results, as tilted one with hexagonal order within the layers. It turned out that both components and the mixture exhibit the ferroelectric smectic C* phase in a wide temperature range. Physical properties of new binary mixture of two ferroelectric liquid crystalline compounds, regarding the properties of the components, were studied. We have shown that certain parameters of organic-metal nanocomposites can be controlled by the appropriate amount of metal admixture. The influence of oleic acid admixture on these parameters is also widely discussed. We present and explain the non-monotonic modification of these parameters with an increase in the nanoparticle concentration. The admixture also causes a significant reduction in the temperature of phase transitions, broadening the SmA* phase at the expense of the SmC* phase and strong streaking of the texture. We show that even the smallest concentration of γ-Fe2O3 nanoparticles largely modifies the parameters of the ferroelectric SmC* phase, such as spontaneous polarization, switching time, tilt angle, rotational viscosity, dispersion anchoring energy coefficient and helix pitch. The detailed research was carried out by using diffraction (PXRD), microscopic (OM, SEM, FCPM, POM), thermal (DSC), optical (TLI), electric and spectroscopic (FTIR) methods. The aim of this paper is to show, by systematic studies, the influence of γ-Fe2O3 nanoparticles on the physical parameters of the liquid crystalline matrix, exhibiting a ferroelectric phase in a wide temperature range.
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