(222f) Solution Combustion Synthesis and Photoelectrochemistry of GaxZn1-XOyN1-Y
- Conference: AIChE Annual Meeting
- Year: 2017
- Proceeding: 2017 Annual Meeting
- Group: Topical Conference: Nanomaterials for Applications in Energy and Biology
- Time: Monday, October 30, 2017 - 5:05pm-5:27pm
We have prepared an array of gallium zinc oxynitrides (GaxZn1-xOyN1-y) as a model system using a combustion synthesis method. Gallium zinc oxynitrides can be synthesized in 30 minutes at 500 oC using this method. X-ray photoelectron spectroscopic analysis reveals that as much as 50% nitrogen substitution in the metal oxide lattice can be achieved, dependent on the ratio of gallium and zinc nitrates used as precursors. XPS also reveals that the nitrogen valency is that of a nitride material, as would be expected for a substitution into the crystal lattice. UV-visible spectroscopy also demonstrates that the band gap of the GaxZn1-xOyN1-ymaterials can be controlled simply by altering the precursor ratio. X-ray diffraction measurements reveal shifts in the crystalline peaks from ZnO toward GaN, confirming the incorporation of nitrogen into the lattice. Of note is that the amount of gallium in the final product is lower than expected, based on the initial precursor mixture. This suggests that at least some of the gallium vaporizes during the reaction.
The as-synthesized products are capable of generating photocurrent from visible light irradiation and are able to carry out water splitting in pure water without any co-catalysts, such as Pt, IrO2, or Rh/Cr2O3. Ongoing work is focused on improving product yield from the reaction, elucidating the effect of the reaction atmosphere on the final product, and maximizing photocurrent yield.