Phase Tuning of Nanostructured Gallium Oxide via Hybridization with Reduced Graphene Oxide for Superior Anode Performance in Li-Ion Battery: An Experimental and Theoretical Study

Abstract

The crystal phase of nanostructured metal oxide can be effectively controlled by the hybridization of gallium oxide with reduced graphene oxide (rGO) at variable concentrations. The change of the ratio of Ga2O3/rGO is quite effective in tailoring the crystal structure and morphology of nanostructured gallium oxide hybridized with rGO. This is the first example of the phase control of metal oxide through a change of the content of rGO hybridized. The calculations based on density functional theory (DFT) clearly demonstrate that the different surface formation energy and Ga local symmetry of Ga2O3 phases are responsible for the phase transition induced by the change of rGO content. The resulting Ga2O3-rGO nanocomposites show promising electrode performance for lithium ion batteries. The intermediate Li-Ga alloy phases formed during the electrochemical cycling are identified with the DFT calculations. Among the present Ga2O3-rGO nanocomposites, the material with mixed α-Ga2O3/β-Ga2O3/γ-Ga2O3 phase can deliver the largest discharge capacity with the best cyclability and rate characteristics, highlighting the importance of the control of Ga2O3/rGO ratio in optimizing the electrode activity of the composite materials. The present study underscores the usefulness of the phase-control of nanostructured metal oxides achieved by the change of rGO content in exploring novel functional nanocomposite materials.

Critical Insight into the Relentless Progression Toward Graphene and Graphene‐Containing Materials for Lithium‐Ion Battery Anodes

“…[ 326 ] Nevertheless, some new hybrids were introduced in the LIB anode fi eld too. Indeed, graphene-containing glassy metal alloy nanofi ber, [ 327 ] selenides, [328][329][330][331][332] silicates, [ 333,334 ] molybdates, [335][336][337] oxides, [338][339][340][341] intermetallic compounds, [ 342,343 ] intermetallic oxides, [ 344,345 ] oxalate, [ 346 ] sulfi de, [ 347 ] nitride, [ 348 ] carbide [ 349 ] and phosphide [ 350 ] hybrids were reported (see Table 2 ). Despite the usual sloping delithiation voltage and the generally low content of graphene (i.e., ≤30 wt%), few of these hybrids [ 329,331,335 ] showed a low 1 st cycle irreversible capacity (i.e., <20%).…”

Uniform gallium oxyhydroxide nanorod anodes with superior lithium-ion storage

“…Combining above results and previous works on Ga-based material, the electrochemical reactions of the GaOOH with lithium can be described with reaction equations as follows: 37,38 GaOOH + 3Li + + 3e GaLi + Li + + e À / GaLi 2…”

2D Materials Based on Main Group Element Compounds: Phases, Synthesis, Characterization, and Applications

“…This mixture phase composite showed significantly higher performance as an electrode in Li-ion batteries than others. [90] Recently, a new form of amorphous Ga 2 O 3 layers was deposited on a flexible substrate at room temperature via radiofrequency magnetron sputtering and then fabricated into a bendable solar-blind photodetector. [91] In 2D forms, few papers on Ga 2 S 3 have been published.…”