Structural, dielectric, and electrical properties of lithium niobate microfibers

Abstract

Lithium niobate (LiNbO 3 ) fibers, obtained from the heat treatment of composite fibers (polymer/inorganic precursors), were successfully prepared by using the blow-spinning technique. A chemical solution containing Li and Nb ions, added to poly(vinyl pyrrolidone) solution, was used as precursor solution. The best condition for producing composite fibers was determined. The morphology of green and crystallized fibers was characterized by scanning electron microscopy (SEM) and revealed fibrous structure with an average diameter around 800 nm. X-ray diffraction (XRD) measurement revealed a pure LiNbO 3 (LN) phase formation. Detailed studies of dielectric response at various frequencies and temperatures exhibited a dielectric anomaly at 364 ℃. The electrical properties (impedance, modulus, and conductivity) of the fibers were studied using impedance spectroscopy technique. The contributions of grain and grain boundary effects were observed in the LN fibers. The activation energy of the composite fibers was found to be 1.5 eV in the high temperature region (325-400 ℃).

Piezoelectric materials as stimulatory biomedical materials and scaffolds for bone repair

“…In a recent study, Bolbasov et al highlighted the importance of controlling the amount of piezoelectric βphase in PVDF-TeFE in order to obtain a better cellular response when compared to electrospun scaffolds [248]. Electrospinning (ES) and SBS have been used to fabricate ceramic or composite fibre using piezoelectric materials [249][250][251][252][253]. Isakov et al fabricated aligned BT nanofibres using ES and characterized their ferroelectric and piezoelectric properties [253].…”

“…Raman spectroscopy and PFM was used to identify the presence of ferroelectric phases [253]. In another study, SBS was used by Cena et al to fabricate lithium niobate (LN) microfibres from sol-gel precursors [251]. The solution used for spinning microfibres was a mixture of poly (vinyl pyrrolidone) (PVP), isopropyl alcohol, water and LN solution (prepared by dissolving lithium carbonate and ammonium niobium oxalate in deionized water) [251].…”

“…In another study, SBS was used by Cena et al to fabricate lithium niobate (LN) microfibres from sol-gel precursors [251]. The solution used for spinning microfibres was a mixture of poly (vinyl pyrrolidone) (PVP), isopropyl alcohol, water and LN solution (prepared by dissolving lithium carbonate and ammonium niobium oxalate in deionized water) [251]. Different electrical measurements such as impedance, modulus and conductivity were carried out after making pellets from fibres.…”

Study of electric conduction mechanisms in bismuth silicate nanofibers

“…At low frequency region, a decrease in Z′ values is observed with temperature. This behavior represents the existence of a negative temperature coefficient of resistance (NTCR) in BiSiO nanofibers [21][22][23] . It is also observed that all spectrums merged into a single spectra at 24 .…”

Hybrid sol–gel inorganic/gelatin porous fibres via solution blow spinning

“…The fibre networks produced typically exhibit more open inter-fibre porosity than electrospun mats [7,8]. A range of materials have been successfully processed to fibres by SBS to date, including polymers [2,3], composites [9,10], ceramic fibres either by incorporating inorganic components in a matrix followed by burn-off of the organic matrix and sintering [11][12][13], and those derived by sol-gel precursors and subsequent calcination [14,15]. Highly porous bioactive composite fibres have been produced by solution blow spinning poly(D,L-lactide) solutions containing nanobioactive glass particles directly into a cryogenic bath followed by lyophilisation [9].…”