Electrochemical performance of composite electrodes based on rGO, Mn/Cu metal–organic frameworks, and PANI

Benzendicarboxylic acid (BDC)-based metal–organic frameworks (MOFs) have been widely utilized in various applications, including supercapacitor electrode materials. Manganese and copper have solid diamond frames formed with BDC linkers among transition metals chosen for MOF formation. They have shown the possibility to enlarge capacitance at different combinations of MOFs and polyaniline (PANI). Herein, reduced graphene oxide (rGO) was used as the matrix to fabricate electrochemical double-layer SCs. PANI and Mn/Cu-MOF's effect on the properties of electrode materials was investigated through electrochemical analysis. As a result, the highest specific capacitance of about 276 F/g at a current density of 0.5 A/g was obtained for rGO/Cu-MOF@PANI composite.

In Situ Synthesis of Polyaniline Based Ceramic Wastes Composites: Dielectric and Electrical Properties

In the present study, ceramic wastes collected from the premises of industrial zone in Peshawar, KP Pakistan were investigated. An effort has been made to recycle and use the ceramic wastes as fillers in polymeric composites. The negative cost ceramic wastes were purified and activated thermally. The elemental composition and pellets of the wastes were investigated through SEM/EDX analysis. Waste/Polyaniline (PANI) composite was synthesized via in-situ free radical polymerization technique. SEM of the composites showed the uniform distribution of fillers particles in the PANI matrix. XRD studies confirmed that the prepared composite material had a face- centered cubic geometry with distinct preferential orientations. Dielectric analysis showed that the materials exhibit active performance at high frequency regions (3MHz to 3GHz) at room temperature. The results show decrease in dielectric losses and capacitance (1.6 pF) at high frequency regions. AC conductivity of the composite has been increased up to 37.95 Scm-1. This revealed the effect of PANI on the ceramic wastes while increasing its conductance performance. This suggests that the composite material can be investigated for use in photovoltaic detectors, electro-responsive capacitors and power applications.

Poly Methyl Methacrylate (Pmma) Based Polyaniline Composite for Ammonia (Nh3) Gas Sensors

Inorganic acids (HCl, H2SO4, and H3PO4) doped-PMMA/PANI composites are prepared by in-situ technique via oxidation-polymerization process. Different techniques such as XRD, FTIR, UV-Visible, four-probe method are used to characterize the composite. Presence of different chemical group of the doped composites is analysed by ATR-FTIR spectroscopic analysis. Charge carrier behaviour of the doped composite is analyzed by UV-Visible spectroscopy. Band gap (Eg) of the doped composites is determined from UV-Visible absorption analysis using Tauc expression. The estimated direct band gap energy (Eg) is found to be 1.93 eV (for HCl doped PMMA/PANI composite), 1.19 eV (for H2SO4 doped PMMA/PANI composite), and 1.71 eV (for H3PO4 doped PMMA/PANI composite), respectively. DC-conductivity is measured with and without magnetic field. Temperature dependent DC conductivity is also measured. In addition, we were discussed the response of ammonia (NH3) gas with polyaniline-based sensor materials.

Adsorption, Equilibrium Isotherm, and Thermodynamic Studies towards the Removal of Reactive Orange 16 Dye Using Cu(I)-Polyaninile Composite

To overcome some of the limitations of activated carbon like efficiency, cost-effectiveness, and reusability, the present work deals with Cu(I)-based polyaniline (PANI) composite for the removal of reactive orange 16 (RO16) dye. Following the synthesis and characterization of formed Cu(I)-PANI composite, the batch experiments performed for the removal of RO16 dye indicated that the composite has the capacity to reduce the coloring from RO16. The experiments were conducted for the study of effects against changes in pH, time, and dose at room temperature, where we observed for a pH impact on the dye adsorption capacity in the range of 2–12. Among all, the optimal RO16 removal was found to be 94.77% at a pH of 4 and in addition, the adsorption kinetics confirmed to be pseudo-second-order with more suitability towards the Langmuir isotherm, where it is presumed to be the formation of a monolayer of dye molecule at the homogeneous absorbent surface. The calculated maximum capacity, qm, determined from the Langmuir model was 392.156 mg/g. Further application of isotherms to attain thermodynamic parameters, a slight positive value of S° for RO16 adsorption was observed, meaning that there is an increased randomness in the irregular pattern at the specific Cu(I)-PANI interface for an adsorption process. This mechanism plays an essential role in maintaining the effects of water pollution; and, based on the analysis therefore, it is prominent that the Cu(I)-PANI composite can be employed as a promising and economical adsorbent for the treatment of RO16 and other dye molecules from the sewage in wastewater.