The impact of zinc ions on electrode material for energy storage in solvothermal-synthesised graphene-zinc oxide nanocomposites

ABSTRACT

The study examines the impact of zinc ions on energy storage in solvothermal-synthesised graphene-zinc oxide nanocomposites. In recent years, there has been extensive research focus on graphene and metal oxides, particularly in heterostructures and composites. These materials have a broad range of applications, like energy storage. Faradaic processes were shown by the observation of redox peaks in the CV analysis of a three-electrode system. The estimated specific capacitances of graphene at scan rates of (1, 50, and 100) mVS⁻¹ were (1250, 562.5, and 390.6) Fg⁻¹. The G-ZnO (2 w%) and G-ZnO (3 w%) gave the specific capacitance of (1354, 750, and 520) Fg⁻¹ and (1422, 818, and 568) Fg⁻¹ at the same scan rates of 1, 50, and 100 mV/s. Applying a potential to the material reveals its pseudo-capacitive properties. The XRD results for G-ZnO (2 w%) and G-ZnO (3 w%) show diffraction peaks at 2θ = 20.56°, 32.95°, 40.69°, 47.41°, 59.02°, and 69.04°, which correspond to the diffraction planes 011, 100, 101, 102, 110, and 200, respectively.

Research highlights

• The study examines the impact of zinc ions on energy storage in solvothermal-synthesised graphene-zinc oxide nanocomposites.

• Faradaic processes were confirmed by the observation of redox peaks in the CV analysis of a three-electrode system.

• The estimation of specific capacitances of graphene was carried out at scan rates of (1, 50, and 100) mVS⁻¹, and it yielded values of (1250, 562.5, and 390.6) Fg⁻¹.

GRAPHICAL ABSTRACT

KEYWORDS:

• Solvothermal methods
• cyclic voltammetry
• capacitance
• energy
• power densities
• electrodes

Acknowledgments

We extend our thanks to all the authors for their valuable contribution to the success of the research.

Disclosure statement

No potential conflict of interest was reported by the author(s).

CRediTs for authorship

Imtiaz Ahmad, Abdul Shakoor, Waleed Ahmad, Azmat Hussain, Aqeela, Saira Iftikhar: method, review, data collection, data curation, software, editing. Imosobomeh L. Ikhioya: conceptualisation, first-draft writing, visualisation and investigation. The manuscript submission has been approved by all authors.

Data accessibility

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