Facile fabrication of polypyrrole/NiOx core‐shell nanocomposites for hydrogen production from wastewater

• Published in: Polymers for advanced technologies Vol. 34; no. 5; pp. 1633 - 1641
• Main Authors: Atta, A., Negm, H., Abdeltwab, E., Rabia, Mohamed, Abdelhamied, M. M.
• Format: Journal Article
• Language: English
• Published: Chichester, UK John Wiley & Sons, Ltd 01.05.2023; Wiley Subscription Services, Inc
• Subjects: bandgap; Enthalpy; Entropy of activation; fabrication; Glass substrates; hydrogen application; Hydrogen production; Nanocomposites; Optical properties; Polymer coatings; Polymers; polypyrrole/NiOx; Polypyrroles; Sewage; Wastewater
• ISSN: 1042-7147; 1099-1581
• DOI: 10.1002/pat.5997

This work highlights testing the polymer nanocomposite for hydrogen gas production from wastewater (sewage water). The in‐situ polymerization technique is used to prepare polypyrrole (PPy) and PPy/NiOx nanocomposite films on a glass substrate. The film's ability to generate hydrogen from sewage water is then evaluated. The XRD and XPS confirmed the formation of two types of NiOX: NiO and Ni2O3. The optical property of the composite is greater than the polymer under the insertion of NiOx as a core for the polymer coating shell, in which the band gap values are 2.25 and 1.81 eV, respectively. The TEM confirmed the PPy/NiOx core‐shell formation, in which the polymer shell (20 nm) coated the NiOX core (170 nm). The electrochemical testing for H2 gas production is carried out through a three‐electrode cell. The effect of light on/off, wavelengths, and temperature on the H2 production is applied. Under off/on light, the produced current density (Jph) value is enhanced from 5 to 16 μA, respectively. The effect of monochromatic light: 440, 540, and 730 nm are tested, and the produced Jph values are −1.28, −1.16, and −1.14 μA cm−2, respectively. In which, the decreasing Jph value with increasing of the monochromatic light confirmed the behavior of the photoelectrode under different optical regions. The Jph values increase from −1.6 to −5.8 μA cm−2 with a rise in temperature from 30 to 55°C. Moreover, enthalpy (ΔH*), activation energy (Ea), and entropy (ΔS*) of thermodynamic processes are determined using the photoelectrode response at different temperatures.