Green synthesis of high-performance gallium oxide supercapacitor: A path to outstanding energy density

Gallium oxide (Ga2O3) powder was prepared by mixing hydrogen peroxide (30% H2O2) with pure gallium metal (99.999%) inside a hydrothermal cell. The resulting white powder was subjected to different characterization techniques. X-ray diffraction (XRD) revealed the presence of multiple crystalline phas...

Full description

Saved in:
Bibliographic Details
Main Authors: Jamal Alnofiay, Ahmed Al-Shahrie, Elsayed Shalaan
Format: Article
Language:English
Published: AIMS Press 2024-11-01
Series:AIMS Materials Science
Subjects:
Online Access:https://www.aimspress.com/article/doi/10.3934/matersci.2024051
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Gallium oxide (Ga2O3) powder was prepared by mixing hydrogen peroxide (30% H2O2) with pure gallium metal (99.999%) inside a hydrothermal cell. The resulting white powder was subjected to different characterization techniques. X-ray diffraction (XRD) revealed the presence of multiple crystalline phases of gallium oxide, including monoclinic β-Ga2O3, and rhombohedral α-Ga2O3, as well as gallium suboxide Ga2O. X-ray photoelectron spectroscopy (XPS) divulged Ga3+ as the dominant oxidation state of gallium in Ga2O3. However, a lower oxidation state, Ga1+, was also detected. Scanning electron microscopy (SEM) images showed a high degree of morphological diversity with a wide variety in shape and size of powder particles. Porosity measurements were performed to determine the total surface area, pore diameter, and pore volume of Ga2O3 powder. The values were found to be 50 m2 g−1, 2.6 nm, and 0.07 cm3 g−1, respectively. Fascinatingly, gallium oxide powder was directly used to fabricate a symmetrical supercapacitor without any binder. Cyclic voltammetry (CV) and galvanostatic charge/discharge (GCD) measurements were performed to examine the electrochemical energy storage capabilities of Ga2O3 powder using 1M KOH as electrolyte. The fabricated supercapacitor demonstrated a maximum specific capacitance of 1176 F g−1, at a current density of 2 A g−1, an energy density of 104.5 Wh kg−1, and a high-power density of 1.6 kW kg−1. Additionally, following 5000 charge-discharge cycles, the supercapacitor demonstrated outstanding capacitance retention stability of 91.18%. The obtained energy density of 104.5 Wh kg−1 is among the highest reported for metal oxide-based supercapacitors. The presence of multiple crystalline phases in the gallium oxide powder likely contributed significantly to the remarkable results observed in this study.
ISSN:2372-0484