Preparation, characterization and dielectric properties of sodium alginate/titanium dioxide composite membranes

Abstract

Sodium alginate/titanium dioxide solid polymer composite membranes were prepared by solution casting method. The electrical, optical and thermal properties of these composite membranes are in great demand for advanced electronic device applications. The present study is aimed at the preparation of dioxide membranes to enhance the conductivity of sodium alginate. The diffraction pattern confirmed the change of sodium alginate polymer matrix structure from amorphous to polycrystalline upon dispersing TiO 2 powder particles into sodium alginate solution. The surface morphology also evidenced the non-crystalline and polycrystalline (containing grains and grain boundaries) nature of formed films. The infrared spectra showed the presence of various functional groups such as-OH, C=O, O-H, C-H and Na-O. The differential scanning calorimeter (DSC) investigation revealed the existence of exothermic/endothermic peaks, melting and crystallization temperatures. Furthermore, the weight loss of all the films was described as a function of temperature. The dielectric properties highlighted the 5 wt% of TiO 2 dispersed in the sodium alginate solution due to its high dielectric constant (ε′), dielectric loss (ε″) and ac-electrical conductivity (σ ac).

Effect of chromium on structural, morphological and electrical properties of lithium ferrite nanoparticles

“…Similar observations were observed in the literature [46]. In addition, the exchange of electrons can be become very high at high frequencies [43,44].…”

“…8 that the ac-conductivity was almost constant up to log f = 3. This can be observed as a result of weak response of the charge carriers at smaller frequencies [43][44][45][46][47]. However, at high frequencies, i.e., above log f = 3, a sharp increasing trend of ac-conductivity was noticed.…”

Spectroscopic and Electrical Properties of Sodium Alginate/TiO2-Carbon Nanotube Composite

“…Particularly, the shape of grains almost seemed to be like stones [28]. Nanocomposite showed new interwoven structure acting as conductive pathway and leading to high conductivity as compared to that of pure NaAlg [29].…”

Use of Titanium Dioxide (TiO2) Nanoparticles as Reinforcement Agent of Polysaccharide-Based Materials

“…Other investigated applications of the sodium alginate-TiO 2 hybrid composite include the separation process, dye-sensitized solar cell, and molecular electronics [30,69,70]. Premakshi et al [30] used a cross-linked SA-based membrane with TiO 2 for dehydration of isopropanol by pervaporation.…”

“…Furthermore, the hybrid composite showed improved mechanical and optical properties compared to a pure sodium alginate film in a dose-dependent manner, which was associated with the hydrogen-bond formation between both components and the increase in the π-conjugated system. Likewise, Padma et al [70] prepared an SA-based membrane reinforced with TiO 2 nanoparticles for molecular electronics applications and found that the membrane-forming solution showed improved dielectric properties and ac-electrical conductivity with better thermal stability (250 • C) than the sodium alginate membrane (180 • C).…”