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Films of chitosan containing sodium iodide were prepared by the solution cast technique. Several films were prepared by dissolving 1 g of chitosan in different 100 ml of 1% acetic acid solution to which 0.5 g, 1.0 g, 1.5 g, 2.0 g and 2.5 g of sodium iodide was added. The electric conductivity of the films measured at room temperature stops increasing after more than 1.5 g of sodium iodide was added. The film with the highest electric conductivity of 4.9 × 10−2 mS/cm was used as an electrolyte to fabricate some thin film solid state batteries with the configuration Zn + ZnSO4 7H2O/electrolyte/X, where X is a metallic oxide such as PbO2, V2O5 and MnO2. The internal resistance of the fabricated batteries are comparable with the internal resistance of batteries reported in the literature.

Silver-chromate glasses xAgl-yAg2O-zCrO3 (x= 64, 67 and 70 mol% and y/z= 1) were prepared by rapid quenching of the melt. The microstructure of the as-quenched samples showed different surface agglomerates which led to non-uniformity in chemical distribution throughout the sample. The presence of potassium, detected by energy dispersive analysis of X-rays EDAX, was due to contamination of potassium nitrate produced during the preparation of Agl via the double decomposition of silver nitrate and potassium iodide. The battery fabricated from the glass with 70 mol % Agl contaminated with potassium showed an unstable discharge compared to the battery fabricated from glass with 70 mol % Agl of AR grade. This was attributed not only to the formation of low-conducting silver iodide but also to low-conducting potassium compounds which increased the internal resistance of the battery leading to a quick drop in cell voltage.

Electrochemical impedance spectroscopy (EIS) is a key method for the characterizing the ionic and electronic conductivity of materials. One of the requirements of this technique is a model to forecast conductivity in preliminary experiments. The aim of this paper is to examine the prediction of conductivity by neuro-fuzzy inference with basic experimental factors such as temperature, frequency, thickness of the film and weight percentage of salt. In order to provide the optimal sets of fuzzy logic rule bases, the grid partition fuzzy inference method was applied. The validation of the model was tested by four random data sets. To evaluate the validity of the model, eleven statistical features were examined. Statistical analysis of the results clearly shows that modeling with an adaptive neuro-fuzzy is powerful enough for the prediction of conductivity.

CdS and CdSe quantum dots (QDs) have been synthesized via successive ionic layer adsorption and reaction for the fabrication of quantum dot-sensitized solar cells (QDSSCs). In this work, several approaches such as incorporation of ZnS passivation layer, scattering layer, treatment with TiCl4, and increasing the TiO2 layer thickness have been applied on TiO2 layer in order to improve the solar cell performance. By passivating the QD-sensitized TiO2 layer with ZnS, the performance of the cells increased due to reduction of charge recombination at the photoanode/electrolyte interface. With a thicker TiO2 layer thickness of 26 μm, further enhancement was observed. The efficiency of the CdS and CdSe QDSSCs improved from 1.06% to 1.48% and from 1.41% to 3.05%, respectively. On the other hand, scattering layer and treatment with TiCl4 did not bring much improvement to the cells.

Complexation between chitosan and orthophosphoric acid is confirmed from the shifting of the carbonyl band in the chitosan acetate spectrum from 1643 cm−1 to 1630 cm−1 and that of the amine band from 1560 cm−1 to 1526 cm−1. H+ is produced through the dissociation of acid as inferred from the existence of the bands at 1076 and 1159 cm−1. In the spectrum of chitosan- , a strong peak centered at ∼1384 cm−1 which can be assigned to the υ(N–O) mode of is observed. The variation in conductivity with A l 2 Si O 5 content has been explained in terms of the changes exhibited in the spectra of chitosan- .

Ionic conductivity of four chitosan based electrolyte systems viz., chitosan–H3PO4, chitosan–H3PO4–Al2SiO5, chitosan–H3PO4–NH4NO3 and chitosan–H3PO4–NH4NO3–Al2SiO5 were studied by impedance spectroscopy in the frequency range from 50 Hz to 1 MHz and varying temperatures from 293 K to 373 K. The sample 0.62 chitosan − 0.38 H3PO4 has the highest room temperature conductivity of (5.36 ± 1.32) × 10−5 S cm−1. The sample 0.615 chitosan-0.377 H3PO4-0.008 Al2SiO5 exhibits the highest ambient conductivity of (1.12 ± 0.18) × 10−4 S cm−1 in the ternary system with filler. In the ternary system with salt but without filler, 0.56 chitosan-0.34 H3PO4–0.10 NH4NO3 has the highest ambient conductivity of (1.16 ± 0.35) × 10−4 S cm−1. The quarternary sample 0.5572 chitosan-0.3383 H3PO4–0.0995 NH4NO3–0.0005 Al2SiO5 has the highest conductivity of (1.82 ± 0.10) × 10−4 S cm−1. All compositions are in weight fraction. The conductivity-temperature relationship is Arrhenian. Results were analyzed using the Rice and Roth model, Jo...

A gel electrolyte system was prepared by dissolving poly(methyl methacrylate) (PMMA) in ethylene carbonate (EC) and propylene carbonate (PC) doped with salicylic acid (SA) and plasticized with dibutyl phthalate (DBP). The composition of the electrolyte was 35 wt% EC-30 wt% PC-5 wt% SA-5wt% DBP-25 wt% PMMA. The presence of a hump at ~760 cm-1 and a shoulder at 1155 cm-1 in the spectrum of SA-DBP indicate the protonation of DBP. The effect of these bands can also be observed in the spectrum of the gel. Hence, SA has dissociated producing H+ which then interacts datively at the oxygen sites of DBP.

Gel polymer electrolytes (GPEs) consisting of polyvinyl alcohol (PVA) and double iodide salts have been prepared using ethylene carbonate (EC) and propylene carbonate (PC). Potassium iodide (KI) and tetramethylammonium iodide (TMAI) were used as mixed salts for making the electrolyte ion conducting. The highest room temperature (298K) conductivity of 12.91 mS·cm-1 is obtained for the GPE containing the double salts in the ratio of 70 wt.% KI:30 wt.% TMAI, whereas the single salt electrolytes, 100 wt.% KI:0 wt.% TMAI and 0 wt.% KI:100 wt.% TMAI have the conductivities of 12.48 and 3.94 mS·cm-1, respectively. Utilizing the highest conducting binary salts electrolyte as the electrolyte medium in dye-sensitized solar cells (DSSCs) produced the highest efficiency (η) of 3.45%.