ABSTRACT
Conducting polymers integrated with metal oxides create opportunities for hybrid capacitive electrodes. In this work, we report a one-pot oxidative polymerization for the synthesis of integrated conductive polyindole/nickel oxide (PIn/NiO), polyindole/zinc oxide (PIn/ZnO), and polyindole/nickel oxide/zinc oxide (PNZ). The polymers were analyzed thoroughly for their composition and physical as well as chemical properties by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible spectroscopy (UV-Vis), and thermogravimetric analysis (TGA). The PIn and its composites were processed into electrodes, and their use in symmetrical supercapacitors in two- and three-electrode setups was evaluated by cyclic voltammetry (CV), galvanostatic discharge (GCD), and electrochemical impedance spectroscopy (EIS). The best electrochemical charge storage capability was found for the ternary PNZ composite. The high performance directly correlates with its uniformly shaped nanofibrous structure and high crystallinity. For instance, the symmetrical supercapacitor fabricated with PNZ hybrid electrodes shows a high specific capacitance of 310.9 F g-1 at 0.5 A g-1 with an energy density of 42.1 Wh kg-1, a power density of 13.2 kW kg-1, and a good cycling stability of 78.5% after 5000 cycles. This report presents new electrode materials for advanced supercapacitor technology based on these results.
ABSTRACT
A polybenzopyrrole@nickel oxide (Pbp@NiO) nanocomposite was synthesized by an oxidative chemical one-pot method and tested as an active material for hybrid electrodes in an electrochemical supercapattery device. The as-prepared composite material exhibits a desirable 3D cross-linked nanostructured morphology and a synergistic effect between the polymer and metal oxide, which improved both physical properties and electrochemical performance. The unprocessed material was characterized by X-ray diffraction, FTIR and UV-Vis spectroscopy, scanning electron microscopy/energy disperse X-ray analysis, and thermogravimetry. The nanocomposite material was deposited without a binder on gold current collectors and investigated for electrochemical behavior and performance in a symmetrical two- and three-electrode cell setup. A high specific capacity of up to 105 C g-1 was obtained for the Pbp@NiO-based electrodes with a gravimetric energy density of 17.5 Wh kg-1, a power density of 1925 W kg-1, and excellent stability over 10,000 cycles.
ABSTRACT
Polybenzopyrrole (Pbp) is an emerging candidate for electrochemical energy conversion and storage. There is a need to develop synthesis strategies for this class of polymers that can help improve its overall properties and make it as suitable for energy storage applications as other well-studied polymers in this substance class, such as polyaniline and polypyrrole. In this study, by synthesizing Pbp in surfactant-supported acidic medium, we were able to show that the physicochemical and electrochemical properties of Pbp-based electrodes are strongly influenced by the respective polymerization conditions. Through appropriate optimization of various reaction parameters, a significant enhancement of the thermal stability (up to 549.9 °C) and the electrochemical properties could be achieved. A maximum specific capacitance of 166.0 ± 2.0 F g-1 with an excellent cycle stability of 87% after 5000 cycles at a current density of 1 A g-1 was achieved. In addition, a particularly high-power density of 2.75 kW kg-1 was obtained for this polybenzopyrrole, having a gravimetric energy density of 17 Wh kg-1. The results show that polybenzopyrroles are suitable candidates to compete with other conducting polymers as electrode materials for next-generation Faradaic supercapacitors. In addition, the results of the current study can also be easily applied to other systems and used for adaptations or new syntheses of advanced hybrid/composite Pbp-based electrode materials.
ABSTRACT
The present study is aimed at the synthesis and exploring the efficiency of a novel activated carbon incorporated polyindole (AC@PIN) composite for adsorptive removal of Malachite Green (MG) dye from aqueous solution. An AC@PIN hybrid material was prepared by in situ chemical oxidative polymerization. The physico-chemical characteristics of the AC@PIN composite were assessed using Fourier-transform infrared spectrometer, X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, ultraviolet visible spectroscopy, and determination of point of zero charge (pHPZC). A series of adsorption studies was conducted to evaluate the influence of operational parameters such as pH, contact time, initial dye concentration, AC@PIN dosage, and temperature on dye adsorption behavior of developed composite. A maximum dye removal percentage (97.3%) was achieved at the pH = 10, AC@PIN dosage = 6.0 mg, initial dye concentration 150 mg L-1, and temperature = 20 °C. The kinetic studies demonstrated that the adsorption of MG on AC@PIN followed pseudo-second-order model (R2 ≥ 0.99). Meanwhile, Langmuir isotherm model was founded to be the best isotherm model to describe the adsorption process. Finally, the recyclability test revealed that the composite exhibits good recycle efficiency and is stable after 5 cycles. The obtained results suggest that AC@PIN composite could be a potential candidate for the removal of MG from wastewater.
ABSTRACT
The synthesis of hydroxy benzophenones and benzophenone-N-ethyl morpholine ethers and the results of anti-inflammatory activity in vivo are described. The structures of the compounds were elucidated by IR, (1)H-NMR, mass spectroscopy and the elementary analysis. The anti-inflammatory activity of the synthesized compounds were determined by carrageenan-induced hind paw oedema test in rats. Most of the tested compounds exhibited anti-inflammatory activity and some of them were more active than standard drugs. In addition ulcerogenic and cyclooxygenase activities are also described.
