https://ogma.newcastle.edu.au/vital/access/ /manager/Index en-au 5 https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:49621 Wed 24 May 2023 12:15:52 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:35394 Wed 24 Jul 2019 11:45:26 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:45366 Cu (∼95.01 to 90.53%) > Cd (∼92.5 to 55.25%) > Ni (∼80.85 to 50.6%), even in the presence of 0.01/0.001 M of CaCl2 and Na2SO4 as background electrolytes and charged organic molecule under an environmentally relevant concentration (200 μg/L). The maximum adsorption capacities of Ni, Cd, Cu, and Pb were calculated as 2.85 ± 0.08, 6.96 ± 0.31, 16.87 ± 1.50, and 26.49 ± 2.04 mg/g, respectively. HNT-BC@Alg has fast sorption kinetics and maximum adsorption capacity within a short contact time (∼2 h). Energy-dispersive X-ray spectroscopy (EDS) elemental mapping exhibited that adsorbed heavy metals co-distributed with Ca, Si, and Al. The reduction of surface area, pore volume, and pore area of HNT-BC@Alg (after sorption of heavy metals) confirms that mesoporous surface (2–18 nm) supports diffusion, infiltration, and interaction. However, a lower range of mesoporous diameter of the adsorbent is more suitable for the adsorption of heavy-metal ions. The adsorption isotherm and kinetics fitted well with the Langmuir isotherm and the pseudo-second-order kinetic models, demonstrating the monolayer formation of heavy-metal ions through both the physical sorption and chemical sorption, including pore filling, ion exchange, and electrostatic interaction.]]> Wed 20 Mar 2024 15:10:50 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:37131 Wed 19 Aug 2020 13:34:43 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:36263 2 and sp³ structures have been identified. The level of functionalization decreases in carbons with reduced amorphous and increased graphitic character. Thermal decomposition of electrodepositied carbons has been investigated and zero order kinetics have been identified. A relationship has been identified between elevated oxygen functionalization and increased pseudo-capacitance, with carbons deposited at 0.15 A cm⁻² showing capacitances of 400 F g⁻¹ in 0.5 M H₂SO₄ at sweep rates of 10 mV s⁻¹.]]> Wed 18 Mar 2020 12:27:30 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:15773 Wed 11 Apr 2018 19:05:14 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:15645 2/electrolyte/graphite interface. Furthermore, a consideration of mass transport processes within the electrode indicates that titanium ions may become incorporated into the γ-MnO₂ lattice upon cycling, impacting H⁺/e⁻ mass transport.]]> Wed 11 Apr 2018 16:57:35 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:15443 2 batteries. Kinetic analysis is used to determine the precise heating regime necessary to, theoretically, completely remove structural water from six different EMD samples. It was found that the oxidation of Mn(III) to Mn(IV) occurred to a greater extent for samples with initially high pyrolusite content and a low fraction of cation vacancies after heat treatment at low temperatures. This same Mn(III) to Mn(IV) conversion was also enhanced after high temperature treatment for those samples with a higher manganese content and low cation vacancy fraction. Additionally, at low heat treatment temperatures the parent γ-MnO₂ structure and cation vacancies were better retained in samples with low starting BET surface area. Finally, this work determined that samples with high BET surface area tend to lose proportionally less of this value as a consequence of heat treatment, compared to those with low initial values.]]> Wed 11 Apr 2018 16:20:21 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:20671 Wed 11 Apr 2018 16:11:32 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:15770 Wed 11 Apr 2018 16:07:16 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:15823 Wed 11 Apr 2018 15:42:37 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:15706 Wed 11 Apr 2018 14:31:47 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:18203 Wed 11 Apr 2018 12:35:50 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:16069 Wed 11 Apr 2018 12:29:52 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:16071 Wed 11 Apr 2018 12:09:08 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:15793 Wed 11 Apr 2018 11:18:16 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:16046 Wed 11 Apr 2018 11:13:53 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:29793 -2 μmol/m²) than that with both CTP-90 (8.47 μmol/g, 4.49 × 10^–2 μmol/m²) and CRP-80 (9.00 μmol/g, 1.19 × 10^–2 μmol/m²).]]> Wed 11 Apr 2018 10:27:43 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:15817 Wed 11 Apr 2018 09:36:55 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:39450 Wed 08 Jun 2022 09:41:19 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:36716 2SO₄ and the synthesized carbons has been investigated in a manner which may be generalised to analyse other supercapacitive systems, and the electrolyte coverage, porosity, and Mott-Schottky behaviour of the materials have been quantified. High, frequency-dependent, capacitances of up to 160 F g⁻¹ have been obtained for carbons deposited at either low temperature or low current density, and for carbons deposited in binary Li₂CO_3–K₂CO₃ eutectics.]]> Tue 27 Feb 2024 14:03:13 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:54416 Tue 27 Feb 2024 13:57:07 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:40006 4, 0.1 M Na₂SO₄ and manganese citrate concentrations of 0, 0.5, 2 or 4 mM. It was found that varying the citrate concentration changed the deposition mechanism by stabilising the Mn³⁺ intermediate formed by the oxidation of Mn²⁺. The different stability of the Mn³⁺ ion affects the rate of nucleation on the surface and subsequent growth of the film. This in turn, affects the morphology of the deposited material. Understanding the effects of the deposition mechanism on the resultant film morphology is necessary to optimise the properties of electrodeposited films for their various applications.]]> Tue 21 Mar 2023 18:27:28 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:36942 -1/2), as well as the residual capacitance and the inverse of the scan rate (v^-1).]]> Tue 21 Jul 2020 11:33:42 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:36941 2SO₄ between 0.0-0.8 V (vs SCE). It was found that in all cases, the specific capacitance was decreased by increasing the sweep rate. The capacitance-sweep rate dependence was only found to be accurate in a short range of low sweep rates. Overall there was good agreement between the SPECS and current-sweep rate dependence models over the full range of sweep rates. However, the SPECS method provided more precise information about the kinetic behavior of the electrochemical cell through a full range of sweep rates.]]> Tue 21 Jul 2020 11:26:42 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:36940 1v + k₂v^1/2, where k₁ and k₂ are constants. Outcomes from the analysis indicate that this approach is complicated by the resistance associated with double layer formation, electrode instabilities in the electrolyte under study, and also increased electrode resistance.]]> Tue 21 Jul 2020 11:19:42 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:36939 Tue 21 Jul 2020 11:19:41 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:36938 + (0.01 M AgNO₃ in ACN) reference electrode. Situated between the opposing AC electrodes, between two separators, is a Pt sensing electrode, the potential of which is either monitored or controlled to explore either electrolyte fluxes during cycling, or the formation of soluble species in the electrolyte, respectively. It was deduced that electrolyte ions are strongly associated with the AC electrodes rather than between the electrodes even without an applied potential. Furthermore, aging of the electrochemical system with cycling (cyclic voltammetry) is also explored. Even with identical electrodes it is noted that the individual electrodes behaved differently as a result of anion versus cation association. Finally, at cell voltages approaching 2 V, oxidation of the positive electrode is observed, liberating species into the electrolyte. The implications of these observations have been discussed.]]> Tue 21 Jul 2020 11:05:42 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:36937 Tue 21 Jul 2020 10:51:42 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:42003 Tue 16 Aug 2022 16:51:26 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:46305 Tue 15 Nov 2022 10:07:55 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:55296 Tue 14 May 2024 15:37:32 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:38192 Tue 10 Aug 2021 16:28:51 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:43824 Tue 04 Oct 2022 11:04:53 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:39829 Thu 28 Jul 2022 08:31:21 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:45176 Thu 27 Oct 2022 14:54:34 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:45332 Thu 27 Oct 2022 10:18:34 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:18438 Thu 25 Jun 2015 13:41:18 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:26869 Thu 16 Mar 2017 14:30:42 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:39605 Thu 16 Jun 2022 09:54:02 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:43377 Thu 15 Sep 2022 16:14:33 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:43305 Thu 15 Sep 2022 13:47:26 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:33540 Thu 15 Nov 2018 15:26:24 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:33541 Thu 15 Nov 2018 15:26:23 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:33542 Thu 15 Nov 2018 15:26:23 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:54296 Thu 15 Feb 2024 14:52:06 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:47936 Thu 09 Feb 2023 15:57:54 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:46822 + reference electrode, individual electrode potentials were measured showing that even though it is a symmetrical device, polarization on the positive electrode was always greater than the negative electrode, implying that the negative electrode capacitance is greater. Deconvolution of the i-t transients from the SPECS experiment across the device voltage window can be accomplished in a similar fashion to the study of a single electrode, in which case geometric and porous capacitances, as well as diffusion and residual processes are identified. Similarly, the components of the i-t transients can be converted into voltametric data, providing access to individual electrode performance over a wide range of sweep rates in the device. The inclusion of a sensing electrode between he positive and negative electrodes is also described, providing insight into electrolyte fluxes and electrode stability within the device.]]> Thu 01 Dec 2022 10:00:23 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:12333 Sat 24 Mar 2018 08:15:53 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:20945 Sat 24 Mar 2018 08:06:05 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:20810 0.30MnO₂ is found to cycle solely with a single-phase mechanism, in contrast to previous literature reports, with only subtle changes in the crystal structure. However, a better cycling discharge capacity is realised through a two-step lithiation synthesis, thermally lithiated Li_0.08MnO₂ which is then electrochemically lithiated to Li_0.33MnO₂. After an irreversible two-phase reaction early in the first discharge, this material cycles by a single-phase reaction with good structural reversibility and a stable unoptimised cycling capacity of 120 mAh/g. Comparing cathodes using a combination of in-situ and ex-situ synchrotron XRD data allows us to rationalise cathodic performance with structure and thereby directing research into promising candidates.]]> Sat 24 Mar 2018 08:05:58 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:17869 Sat 24 Mar 2018 08:03:31 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:17415 600 mA g⁻¹), where the material discharges 154 and 135 mA h g⁻¹ capacity at a discharge rate of 1000 and 2000 mA g⁻¹, respectively, compared to 132 and 83 mA h g⁻¹ for EMD under the same conditions.]]> Sat 24 Mar 2018 08:01:38 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:17438 Sat 24 Mar 2018 08:01:36 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:19660 Sat 24 Mar 2018 08:01:10 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:21155 Sat 24 Mar 2018 08:00:18 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:17238 Cl > Br > I. Substitution with electron-donating tert-butyl and methoxy groups acted as electron donating groups, and decreased the formal potential by 150–190 mV. Substitution in the 4,4′ positions, irrespective of electron withdrawing or donating character, also imparted an asymmetry in the anodic peak in the cyclic voltammograms, where the oxidation process became more sluggish than the corresponding reduction. Kinetics of Co(II) oxidation was evaluated by Koutecký–Levich analysis at a rotating Pt disc, revealing superior oxidation kinetics of the un-substituted 2,2′-bipyridine complex by up to an order of magnitude or larger. The anodic transfer coefficients were also extracted from this analysis, revealing ideal α = 0.50 for the parent complex, to 0.70 ≤ α ≤ 0.88 for complexes with substituted ligands.]]> Sat 24 Mar 2018 07:59:14 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:18953 Sat 24 Mar 2018 07:58:57 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:17748 2 was performed using two techniques, namely, the induction period and iso-conversional methods. The modelling and analysis arising from thermogravimetric studies of the material gave rise to the pre-exponential factor and, most importantly, the activation energy for the transition. Analysis using the induction period showed the activation energy to increase linearly with extent of conversion, ranging from 109–250 kJ mol⁻¹, while the iso-conversional method gave values in the range 66–76 kJ mol⁻¹, with higher values for both lower and higher extents of conversion. Comparison of these methods indicates that the iso-conversional method is the preferred technique for determining the kinetic parameters for this process. Overall, this allows for the determination of the optimum heat treatment temperature and time for the γ-MnO₂.]]> Sat 24 Mar 2018 07:57:20 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:20698 xMnO₂). At a 4.3 mA g⁻¹ discharge rate, HT-EMD undergoes a simultaneous two-phase transformation and solid solution reaction for 0 0.34) formed in the two phase process. At higher discharge rates (17.1 mA g⁻¹), no evidence for the new lithiated phase is observed, suggesting the discharge mechanism is rate dependent. These findings represent a key step in understanding the mechanistic behaviour of HT-EMD in primary battery systems, which in turn will assist in optimizing battery performance characteristics and broadening possible electronic applications.]]> Sat 24 Mar 2018 07:55:40 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:21099 Sat 24 Mar 2018 07:53:59 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:21102 Sat 24 Mar 2018 07:53:58 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:19411 Sat 24 Mar 2018 07:52:06 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:28282 Sat 24 Mar 2018 07:41:22 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:27956 Sat 24 Mar 2018 07:38:46 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:27800 Sat 24 Mar 2018 07:37:21 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:26800 Sat 24 Mar 2018 07:36:26 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:29538 Sat 24 Mar 2018 07:32:27 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:27746 DL) and diffusion-limited pseudo-capacitance (C_D) at scan rates ranging from 0.08 to 125 mV/s. The relative contributions from each process are related to the physicochemical properties of the electrode. Additionally, the effects of these electrode properties on the overall performance of each system, in terms of specific power and energy, are identified.]]> Sat 24 Mar 2018 07:27:45 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:27747 Sat 24 Mar 2018 07:27:45 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:27748 Sat 24 Mar 2018 07:27:45 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:24763 Sat 24 Mar 2018 07:14:08 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:24537 Sat 24 Mar 2018 07:11:34 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:24734 3+ intermediate is a key feature of this electrodeposition mechanism, the formation of which is dependent on the substrate, which in this case is either platinum, MnO₂ or MnOOH. On the platinum surface, for all electrolytes, soluble Mn³⁺ is produced initially. The stability of this soluble Mn³⁺ species determines the initial morphology, and rate of change of mechanism for the process. In a neutral electrolyte, nucleation and growth of MnO₂ occurs primarily through the precipitation of a 2D film of MnOOH on the platinum, which rapidly covers the surface. Nucleation in an acidic H₂SO₄ system occurs primarily via a disproportionation route which forms 3D MnO₂ hemispheroids that cover the substrate slowly. Subsequent growth of MnO₂ in both electrolytes then proceeds via formation of a MnOOH film, which is subsequently oxidized in the solid state to form MnO₂. MnOOH oxidation to MnO₂ appears kinetically limited, which is overall a limiting factor in the electrodeposition process.]]> Sat 24 Mar 2018 07:10:58 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:55784 Sat 22 Jun 2024 12:40:42 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:47779 Mon 30 Jan 2023 10:24:22 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:48889 Mon 29 Jan 2024 18:53:21 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:40291 Mon 29 Jan 2024 18:49:50 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:52920 500 °C to conduct both reactions in STCH, could operate at lower temperatures and ΔT = 0 °C. Reaction conditions were evaluated showing that it may also be possible to increase the oxygen partial pressure while still achieving high fuel conversion, which would not be possible operating under the conventional SOE and STCH conditions.]]> Mon 29 Jan 2024 18:27:42 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:46656 Mon 29 Jan 2024 18:02:50 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:46626 2 atmosphere when compared with a N₂ atmosphere, where mass transport limitations in the anode compartment and the additional two-electron oxidation pathway from CO contribute. This hypothesis is verified by comparing the slurry arrangement to a solid working anode where mass transport is not required. In order to maximize the carbon utilization efficiency, operating below the thermodynamic temperature limit for reverse Boudouard gasification (700 °C) is recommended with agitation in slurry-based systems. For a maximum power output, operating under CO₂ at higher temperatures (>800 °C) and passing the CO containing flue gas over an oxygen reduction cathode achieve optimal results.]]> Mon 28 Nov 2022 13:29:36 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:47594 Mon 23 Jan 2023 14:56:26 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:33883 2+.]]> Mon 21 Jan 2019 15:57:47 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:33879 Mon 21 Jan 2019 15:50:49 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:51791 Mon 18 Sep 2023 15:18:56 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:36848 2CO₃-Na₂CO₃-K₂CO₃ eutectic is used to produce highly amorphous carbon with considerable oxygen functionalization in a process focusing on the conversion of CO₂ to value-added carbon. Electrochemical characterization of materials using multiple techniques in different electrolytes allowed for the optimization of these materials as electrochemical capacitor electrodes. Variation in capacitive performance of the investigated materials has been provided based on their physical characteristics. The synthesized carbons are hybrid materials, showing both pseudocapacitive and electric double layer contributions to the total performance. Annealing under nitrogen at 800 °C is shown to widen pores in the carbon material, resulting in an increase in medium scan rate (5-10 mV.s^-1) capacitance. A stable specific capacitance of 425 F.g^-1 is obtained at 5 mV s^-1 in 0.5 M Na₂SO₄ after 1000 cycles.]]> Mon 13 Mar 2023 14:32:38 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:48830 Mon 10 Apr 2023 10:35:30 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:46875 4)₂SO₄ and (NH₄)₂HPO₄ as well as temperature is examined on the hydrothermal carbonization of glucose, fructose and sucrose. Increasing the temperature from 160 to 220 °C increased the yield of hydrothermal carbon for each saccharide for the (NH₄)₂SO₄ solution, whereas (NH₄)₂HPO₄ produced a yield that was independent of temperature. The addition of (NH₄)₂SO₄ increased the yield obtained at 220 °C by 4.27, 7.03 and 2.01 wt% for glucose, fructose and sucrose over the baseline salt free solution, respectively. (NH₄)₂SO₄ also increased the quantity of acid produced and the average size of the hydrothermal carbon spheres. Conversely, (NH₄)₂HPO₄ produced carbon structures consisting of interlocked spherical shapes and produced almost no acidic products. XPS analysis revealed that (NH₄)₂SO₄ incorporated nitrogen and sulfur into the hydrothermal structure, while (NH₄)₂HPO₄ only allowed nitrogen to be incorporated. It was assessed that NH₄⁺ enhances the production of hydrothermal carbon, except in the presence of PO₄³⁻, which prevents the reaction from effectively forming hydrothermal carbon and organic acids.]]> Mon 05 Dec 2022 09:19:32 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:54595 Mon 04 Mar 2024 08:35:45 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:37206 2SO₄ electrolyte carbon hollow spheres provide much better overall capacitance values as compared to high surface area activated carbon due to the better surface area utilization particularly at large scan rates. Carbon hollow spheres exhibited 74% more specific surface area utilization for energy storage as an electrode material in comparison to activated carbon in 0.5 M Na₂SO₄ solution. When, overall capacitance is divided in to the fragment capacitances in terms of geometric, porous and diffusional contents; morphology of hollow spheres played an important role while in the non-aqueous solutions specific capacitance values remained dependent on the specific surface area of the carbon material. Diffusional fragment of capacitance values in carbon hollow spheres remained limited because of limited thickness of the hollow shells. In this study, at 1 mV s⁻¹ carbon hollow spheres with 29 nm shell thickness and with a specific surface area of 1523 m² g⁻¹ exhibited a specific capacitance values of 105 F g⁻¹ and 127 F g⁻¹ as compared to 85 and 121 F g⁻¹ for activated carbon with a specific surface area of 1895 m² g⁻¹ in 0.5 M sodium sulfate and 1.0 M TEABF₄ respectively.]]> Mon 03 Apr 2023 11:52:29 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:33876 Fri 30 Aug 2019 13:07:57 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:43563 Fri 23 Sep 2022 11:43:37 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:33858 Fri 18 Jan 2019 15:58:46 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:39676 Fri 17 Jun 2022 15:39:15 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:46146 4NO₃ and FeS₂, a major component of reactive ground. Voltammetric processes corresponding to the Fe(II)/Fe(III) redox couple and the reduction of nitrate are observed. This is significant as the existing reaction mechanism shows nitrate reacting in the electrolyte, but not being reduced on the surface of the FeS₂. An irreversible oxidation occurs at ~0 V versus SCE associated with the re-oxidation of species formed at lower potentials. This is not associated with a change in the potential of the electrolyte, indicating a surface reaction. With the use of thermocouples, an exothermic reaction above 0.4 V is observed. FeS₂ is initially unreactive in NH₄NO₃ solutions. After FeS₂ exposure to potentials above 0.6 V versus SCE, the material becomes active and catalytic in nature. Material reacted following the industry standard Australian Explosives Industry Safety Group (AEISG) test method shows similar catalytic behaviour in the presence of fresh NH₄NO₃. This is significant for the safety and testing of reactive ground, as even FeS₂ that has completed reaction still has the potential to undergo further reaction if introduced to fresh NH₄NO₃.]]> Fri 11 Nov 2022 18:30:55 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:26455 Fri 10 Jul 2020 13:31:04 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:36855 2g^-1 have been produced through the electrolytic reduction of molten Li₂CO_3-K₂CO_3-Na₂CO₃ at the eutectic composition (43.5:25:31.5 mol%) onto /graphite at 600 °C and 0.30 A cm^-2 under a 60 mL min^-1 CO₂ gas flow. These carbons have been shown to consist largely of amorphous carbon with some spherical and flake-like conglomerates. Functionalised oxygen has been observed in synthesised carbons using FTIR and XPS. Synthesised carbons have been investigated in 3-electrode cells and analysed using cyclic voltammetry and step potential electrochemical spectroscopy (SPECS) at room temperature. Capacitances as high as 450 F g^-1 have been observed at 0.0833 mV s^-1 scan rates. The EDLC and pseudo-capacitive behaviour of produced carbons have been analysed and it has been found that the produced carbons behave hybrid capacitors with considerable pseudo-capacitive contributions. The performance of synthesised carbons has been compared to that of activated carbon derived through the chemical activation of carbon from the pyrolysis of coconut husks and to the reported capacitances of commercial activated carbons.]]> Fri 10 Jul 2020 13:30:07 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:36718 −1 have been obtained at scan rates of 10 mV.s⁻¹. With respect to temperature of carbon deposition, carbon electrodeposited at 500°C has been identified as the best electrical double layer capacitor type material, and as a superior material for pseudocapacitive applications. The performance of a control activated carbon has been compared with the electrodeposited carbons, and it has been shown that, when electrodeposited at low current densities, the resultant carbon performance is superior to the activated carbon.]]> Fri 10 Jul 2020 12:56:42 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:40339 Fri 08 Jul 2022 10:26:32 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:42762 Fri 02 Sep 2022 08:47:17 AEST ]]>