https://ogma.newcastle.edu.au/vital/access/ /manager/Index en-au 5 https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:37282 cat⁻¹ h⁻¹ and a Faradaic efficiency as high as 8.3% at a low overpotential (0.05 V vs the reversible hydrogen electrode), which is far better than that of the bulk Ru counterpart. Moreover, the Ru SAs/g-C₃N₄ displays a high stability during five recycling tests and a 12 h potentiostatic test. Density functional theory calculations reveal that compared to bulk Ru surfaces, Ru SAs/g-C₃N₄ has more facile reaction thermodynamics, and the enhanced NRR performance of Ru SAs/g-C₃N₄ originates from a tuning of the d-electron energies from that of the bulk to a single-atom, causing an up-shift of the d-band center toward the Fermi level.]]> Tue 05 Sep 2023 11:57:42 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:41019 Thu 21 Jul 2022 12:08:17 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:39079 particle) on the physicochemical properties and the reactivity of S-nZVI remains unknown. Here, we synthesized S-nZVI via one co-sulfidation and three post-sulfidation methods to determine how different sulfur reagents and addition procedures affect the reactivity of S-nZVI for defluorination. The measured S amounts of co-sulfidized S-nZVI and post-sulfidized S-nZVI was much lower than their dose. Different sulfur reagents and sulfidation approach would affect the amount and speciation of sulfur in the particles. Sulfidation of nZVI improved the reactivity for dechlorination (up to 12-fold) and defluorination (up to 3-fold) of florfenicol (FF), but inhibited the reactivity with water (up to 31-fold). Density functional theory calculations showed that sulfidation increases the hydrophobicity of materials, and the amount and nature of sulfur affect the hydrophobicity and the number of blocked H sites. S-nZVI particles with more S^2- and S₂^2- species showed faster dechlorination and defluorination of FF. Up to ~ 45% of FF was defluorinated by S-nZVI after 15 days reaction at room temperature and pressure. The [S/Fe]_particle and Fe⁰ content was responsible for the initial and long-term defluorination, respectively. These results suggest that S-nZVI could be a promising agent for defluorination, and the sulfur reagents and sulfidation approach would affect its properties and reactivity.]]> Thu 05 May 2022 16:35:19 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:45543 4 or Fe-N₄ planar configuration. The developed Ni-N₄/GHSs/Fe-N,₄ Janus material exhibits excellent bifunctional electrocatalytic performance, in which the outer Fe-N₄ clusters dominantly contribute to high activity toward the oxygen reduction reaction (ORR), while the inner Ni-N₄ clusters are responsible for excellent activity toward the oxygen evolution reaction (OER). Density functional theory calculations demonstrate the structures and reactivities of Fe-N₄ and Ni-N₄ for the ORR and OER. The Ni-N₄/GHSs/Fe-N₄ endows a rechargeable Zn–air battery with excellent energy efficiency and cycling stability as an air-cathode, outperforming that of the benchmark Pt/C+RuO₂ air-cathode. The current work paves a new avenue for precise control of single-atom sites on carbon surface for the high-performance and selective electrocatalysts.]]> Mon 29 Jan 2024 18:00:27 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:50076 Fri 30 Jun 2023 12:37:14 AEST ]]>