Density functional theory investigation of the energy storage potential of graphene-polypyrrole nanocomposites as high-performance electrode for Zn-ion batteries

The present research explores, through the density functional theory (DFT) calculations, the viability of graphene-polypyrrole (G/PPy) nanocomposites as an effective material for energy storage in Zn-ion batteries. To this end, the CASTEP calculator in the Materials Studio software was employed to examine the electronic and structural properties of the nanocomposites and their potential to enhance energy storage capabilities of Zn-ion batteries. Specifically, the study investigates the interaction of the Zn-adatom with the nanocomposites, electronic properties, specific capacity, Zn adatom diffusion behavior, structural, and thermal stability, as well as the mechanisms through which the nanocomposites store energy. The results show that the adsorption calculation for PPy onto the graphene nanosheet has an exothermic adsorption energy of -1.68 eV and an adsorption height of 3.28 & Aring;. The loading of Zn atoms onto the Gr/PPy nanocomposite yielded a maximum specific capacity of 510.12 mAh g(-1), resulting into a weak adsorption energy of -0.078 eV. The nano composite exhibited an extremely low Zn diffusion barrier of 12 meV, enabling a fast Zn diffusion on its surface. These findings suggest that G/PPy nanocomposites hold promise as a material to enhance energy storage in Zn-ion batteries. The study, through DFT calculations, offers valuable insights into the electronic and structural properties of G/PPy nanocomposites and their potentials for improved energy storage in Zn-ion batteries. It thus, contributes significantly to the current understanding of energy storage materials and provides a foundation for further research on the development of more effective and efficient energy storage solutions.