Influence of Ta₂O₅ on polyaniline surface for liquid petroleum gas sensing applications

Abstract

Purpose -The purpose of this paper is to study the sensitivity and selectivity properties of polyaniline/tantalum pentoxide (PANI/Ta 2 O 5 ) composite to liquid petroleum gas (LPG). Design/methodology/approach -Polyaniline/tantalum pentaoxide (PANI/Ta 2 O 5 ) composites were synthesized by in situ chemical polymerization method using ammonium persulphate as an oxidizing agent. This is the novel polymerization process for the direct synthesis of emeraldine salt phase of the polymer. The composites were characterized by FTIR, XRD and SEM. Temperature dependence conductivity of the composites shows thermally activated behaviour. Sensitivity and selectivity of the composites are studied. Findings -The PANI/ Ta 2 O 5 composites of 20 wt% and 30 wt% are showing maximum change in resistance against time when compared to pure PANI and other polyaniline composites when exposed to LPG. The 20 wt % composites show maximum sensitivity of 83% to LPG. The selectivity studies reveals that LPG could be sensed better when compared to oxyacetylene and other test gases. Practical implications -Selectivity studies have been carried out and the sensor proved to be better than metal oxides sensors. Social implications -The sensing material is of low cost. Originality/value -To the best of the authors' knowledge, studies on Ta 2 O 5 -based gas sensor have not been reported previously.

Synthesis, characterization, dielectric and rectification properties of PANI/Nd2O3:Al2O3nanocomposites

“…Figure 12 shows the plot of σ ac as a function of frequency for pure PANI and PANI/Nd 2 O 3 :Al 2 O 3 nanocomposites of various weight percentages in the frequency range from 10 2 to 10 6 Hz. The AC conductivity remains constant up to 10 5 Hz, and thereafter, it increases steeply, which is a characteristic feature of disordered materials. At higher frequencies, σ ac increases because of contribution of polarons, which are moving along smaller and smaller distances in a polymer chain.…”

“…There are several good reviews on synthesis, physicochemical, and electrochemical properties of PANI and its blends. [3][4][5] Membranes for gas separation with high selectivity, [6] electromagnetic shielding, [7] biosensors, [8,9] and humidity sensors [10] are among the promising applications of PANI containing organic composite films.…”

“…Among various conducting polymers, polyaniline (PANI) is a promising candidate for practical applications because of its environmental stability, easy processability, controlled reversibility of electrical properties, and commercial availability. There are several good reviews on synthesis, physicochemical, and electrochemical properties of PANI and its blends . Membranes for gas separation with high selectivity, electromagnetic shielding, biosensors, and humidity sensors are among the promising applications of PANI containing organic composite films.…”

Surface Modified ${\rm CaTiO}_{3}$ Loaded in Polyaniline by Sodium Dodecyl Benzene Sulphonic Acid for Humidity Sensor

“…SEM micrograph of polyaniline and polyaniline-CaTiO 3 nanocomposites employed in the present investigation shows semi crystalline behavior. Under such conditions a uniform crystallite is surrounded by amorphous regions [23].…”

Design of a Low Cost Instrumentation System for Oxygen Sensing Using Polyaniline/Cerium Oxide Composites

“…Several studies have been reported in the literature for detection of various gases using metal oxide sensors [1][2][3][4][5][6][7][8][9][10][11]. Huge number of gas sensors are commercially available in the market which employ metal oxides.However,these sensors operate at high temperatures and their electrical conductivity depends on the concentration of ambient gas.…”