https://nova.newcastle.edu.au/vital/access/ /manager/Index ${session.getAttribute("locale")} 5 https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:45067 Wed 26 Oct 2022 11:43:26 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:35508 Wed 24 Jun 2020 14:44:42 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:37201 0.5Zn_0.5S@halloysite nanotubes tertiary structure is designed via facile in situ assembly, which settles all the above‐mentioned issues and achieves exceptional and stable photocatalytic H₂ evolution and storage. Significantly, EDTA grafted on halloysites as the hole (h⁺) traps steers the photogenerated h⁺ and electrons (e−) from Cd_0.5Zn_0.5S separately to halloysites and outer surface Pt sites, achieving efficient directional separation between h+ and e− and inhibiting the h⁺‐dominated photocorrosion occurring on Cd_0.5Zn_0.5S. Benefiting from these advantages, the hierarchy shows an unprecedented photocatalytic H₂ evolution rate of 25.67 mmol g⁻¹ h⁻¹ with a recording apparent quantum efficiency of 32.29% at λ = 420 nm, which is seven‐fold that of Cd_0.5Zn_0.5S. Meanwhile, an H₂ adsorption capacity of 0.042% is achieved with the room temperature of 25°C and pressure of 2.65 MPa. This work provides a new perspective into designing hierarchical structure for H₂ evolution, and proposes an integration concept for H₂ evolution and storage.]]> Wed 24 Jan 2024 15:11:12 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:46459 2 batteries using a mild electrolyte have attracted considerable interest because of their high output voltage, high safety, low cost, and environmental friendliness. However, poor cycling stability remains a significant issue for their applications. Equally, the energy storage mechanism involved is still controversial thus far. Herein, porous polyfurfural/MnO₂ (PFM) nanocomposites are prepared via a facile one-step method. When tested in a rechargeable aqueous Zn–MnO₂ cell, the PFM nanocomposites deliver high specific capacity, considerable rate performance, and excellent long-term cyclic stability. Based on the experimental results, the role of the hydrated basic zinc sulfate layer being linked to the cycling stability of the aqueous rechargeable zinc-ion batteries is revealed. The mechanistic details of the insertion reaction based on the H⁺ ion storage mechanism are proposed, which plays a crucial role in maintaining the cycling performance of the rechargeable aqueous Zn–MnO₂ cell. We expect that this work will provide an insight into the energy storage mechanism of MnO₂ in aqueous systems and pave the way for the design of long-term cycling stable electrode materials for rechargeable aqueous Zn–MnO₂ batteries.]]> Wed 23 Nov 2022 14:25:58 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:49498 Wed 22 Nov 2023 15:05:51 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:37134 3+ doping in Co₃O₄ spinel remains poorly understood, mainly because the surface state of a catalyst is difficult to characterize. Herein, a bifunctional oxygen electrode composed of spinel Co₂FeO₄/(Co_0.72Fe_0.28)_Td(Co_1.28Fe_0.72)_OctO₄ nanoparticles grown on N‐doped carbon nanotubes (NCNTs) is designed, which exhibits superior performance to state‐of‐the‐art noble metal catalysts. Theoretical calculations and magnetic measurements reveal that the introduction of Fe³⁺ ions into the Co₃O₄ network causes delocalization of the Co 3d electrons and spin‐state transition. Fe³⁺ ions can effectively activate adjacent Co³⁺ ions under the action of both spin and charge effect, resulting in the enhanced intrinsic oxygen catalytic activity of the hybrid spinel Co₂FeO₄. This work provides not only a promising bifunctional electrode for zinc–air batteries, but also offers a new insight to understand the Co‐Fe spinel oxides for oxygen electrocatalysis.]]> Wed 19 Aug 2020 15:05:43 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:37126 Wed 19 Aug 2020 12:10:45 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:37373 Wed 14 Jun 2023 10:42:21 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:35548 -1 h^-1), and durability for H₂O₂ electrogeneration by the two-electron pathway of ORR.]]> Wed 04 Dec 2019 11:57:34 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:38917 2O₂ due to the isolation of the Au nanoparticles (AuNPs) from the PtNPs layer. Then the weak acidity of H₂O₂ can trigger the disassembly and reassembly of the AuNPs, resulting in the Janus distribution of large AuNPs aggregates. Such reconstruction of JMPA leads to the contact between PtNPs and AuNPs aggregates, thus changing the propulsion mechanism to self-electrophoresis. The asymmetric and aggregated AuNPs also enable the generation of a thermal gradient under laser irradiation, which propels the JMPA nanomotors by self-thermophoresis. Such multi-phoretic propulsion offers considerable promise for developing advanced nanomachines with a stimuli-responsive switch of propulsion modes in biomedical applications.]]> Wed 02 Mar 2022 15:43:14 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:36354 -2 and TiO₂-based fuel cell had an open-circuit voltage of 1.34 V. This study opens an available field to develop power cells taking advantage of both chemical energy and solar energy.]]> Tue 28 Mar 2023 12:00:53 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:36650 Tue 23 Jun 2020 14:49:43 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:35392 −2, and the corresponding Tafel slopes of 51.8 and 108mV dec⁻¹, respectively. Otherwise, the CoS₂@N-GN hybrid also presents superior long-term catalytic durability. Moreover, an alkaline water splitting device assembled by CoS₂@N-GN as both anode and cathode can achieve a low cell voltage of 1.53 V at 60◦C with a high faraday efficiency of 100% for overall water splitting. The tremendously enhanced electrochemical behaviors arise from favorable factors including small sized, homogenously dispersed novel CoS₂ nanocrystals and coupling interaction with the underlying conductive nitrogen-doped graphene, which would provide insight into the rational design of transition metal chalcogenides for highly efficient and durable hydrogen and oxygen-involved electrocatalysis.]]> Tue 23 Jul 2019 15:27:22 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:36349 13C isotopic labeling. This work develops precursor microstructure engineering as a promising strategy for rational design of unordinary g-C₃N₄ structure for renewable energy production.]]> Tue 19 Sep 2023 15:05:56 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:36477 2 sheets with excellent stable Pt-like HER performance. A simple and repeatable strategy has been developed via the use of the cheap, simple small organic molecule urea as a reducing agent. We confirm that N doping can induce a disordered surface lattice and increase the number of proton adsorption sites with a relatively weak binding force. Owing to the cooperative effects of surface N doping, disordered surface distortion and the intrinsic nature of MoO₂, high HER activity can be achieved, with an overpotential of η = 96 mV vs. RHE at a current density of −10 mA cm−2 and a Tafel slope of 33 mV per decade. Moreover, we further extended the synthesis method to Ni and Co systems with the formation of N–NiO/Ni and N–CoO/Co core–shell structures, which exhibited enhanced HER performance in comparison with bare MO/M (M = metal) samples. This study can help us design new earth-abundant electrocatalysts with further enhancements in catalytic performance.]]> Tue 19 May 2020 13:15:39 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:40873 Tue 19 Jul 2022 14:24:26 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:41984 Tue 16 Aug 2022 15:55:23 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:41889 2B₂O₇ (CBBO) and SrBi₂B₂O₇ (SBBO) via solid-phase reaction. The crystal structure, microstructure and optical properties were investigated. The photocatalytic activities were studied by decomposition of tetracycline hydrochloride (TH) and evolution of reactive oxygen species (ROS) under UV light irradiation. The results revealed that CBBO and SBBO exhibit benign TH degradation activity with certain mineralization abilities. Within 4 min illumination, almost 70% and 58% of tetracycline hydrochloride was degraded by CBBO and SBBO, respectively. The quantitative capture experiment of radicals showed that the production rate of radical ^·OH and radical ^·O₂− was determined to be 1.27 × 10^-7 and 10.98 × 10^-7 mol·L^-1 min^-1 for CBBO and 1.01 × 10^-7 and 11.75 × 10^-7 mol·L^-1 min^-1 for SBBO, respectively. Density functional theory (DFT) calculation results demonstrated that CBBO has smaller effective masses of electrons and holes than SBBO, which results in higher charge separation efficiency and photocatalytic activity. This work provides two new layered bismuth-based borate photocatalysts for photocatalytic environmental applications.]]> Tue 16 Aug 2022 10:16:38 AEST ]]> https://nova.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://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:38073 -1 h^-1, which is 2.78 times higher that of pristine g-C₃N₄. The largely strengthened photocatalytic CO2 reduction activity mainly originates from the formation of Z-scheme band structures between g-C₃N₄ and Bi₂O₂[BO₂(OH)] benefiting for the efficient charge separation, which was confirmed by the photoeletrochemical, photoluminescence and ESR spectra. This study provides a new reference for fabrication of high-performance Z-scheme photocatalysts for CO₂ reduction.]]> Tue 03 Aug 2021 13:27:42 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:46491 Thu 24 Nov 2022 12:01:02 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:46490 Thu 24 Nov 2022 11:52:53 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:41019 Thu 21 Jul 2022 12:08:17 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:35273 xO_yI_z/g-C₃N₄, namely, g-C₃N₄/BiOI, g-C₃N₄/Bi₄O₅I₂, and g-C₃N₄/Bi₅O₇I. g-C₃N₄/BiOI is prepared by a direct precipitation method, and g-C₃N₄/Bi₄O₅I₂ and g-C₃N₄/Bi₅O₇I are obtained by in situ calcination transformation of g-C₃N₄/BiOI at different temperature. Among them, g-C₃N₄/BiOI and g-C₃N₄/Bi₄O5I₂ are type-I heterojunction, and g-C₃N₄/Bi₅O₇I belongs to type-II heterojunction. The photocatalyitc activity is surveyed by decomposition of diverse industrial contaminants, including methyl orange, bisphenol A and tetracycline hydrochloride under visible light irradiation (λ > 420 nm). It is found that g-C₃N₄/Bi₅O₇I shows largely enhanced photodegradation performance compared to g-C₃N₄/BiOI and g-C₃N₄/Bi₄O5I₂. The much higher photocatalytic activity of g-C₃N₄/Bi₅O₇I is attributed to the enhanced specific surface area, more efficient charge separation and surface transfer efficiency and increased density of charge carriers owing to the formation of type-II heterojunction. The study provides a reference for in situ fabrication of hierarchical photocatalysts with diverse heterojunction types for optimizing photocatalytic activity.]]> Thu 17 Jun 2021 12:50:03 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:46425 2 hierarchical nanotubes with high pre-intercalated K cation content (a-K_0.19MnO₂) are proposed as a superior cathode for ZIBs. Specifically, the a-K_0.19MnO₂ nanotubes are prepared via a self-sacrificial template method, including a neutral solvent hydrothermal intercalation and a subsequent annealing phase transformation process. When tested as cathodes for ZIBs, a subsequent H⁺ and Zn²⁺intercalation mechanism at different voltage platforms is clarified. The water-solvated H⁺ first inserts into tunnel cavities and the subsequent insertion of Zn²⁺ into MnO₂ partially changes the MnO₂ phase from a tunnel-type structure to a layered-type structure (Zn-buserite). The high content pre-intercalated K cations in the layered-type matrix as pillars stabilize the layered structures and expand Zn²⁺ migration channels, which can facilitate the diffusion of Zn2⁺ in the MnO₂ cathodes. It is noteworthy that, a K-salt additive is employed to maintain the concentration of K⁺ in the electrolyte with the aim of inhibiting the extraction of K⁺ from the a-K_0.19MnO₂ host material during cycling, thereby further boosting the cycling ability.]]> Thu 12 Oct 2023 15:30:24 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:46657 3), electrocatalytic nitrogen reduction reactions (NRRs) under ambient conditions using renewable energy sources (e.g. solar) have attracted significant attention; however, the design of an efficient electrocatalyst for the NRR is a challenging task and has been of central research interest. Herein, we report the synthesis of ruthenium(iii) polyethyleneimine (Ru(iii)-PEI) catalysts supported on carboxyl-modified carbon nanotubes (Ru(iii)-PEI@MWCNTs) by a self-assembly process driven by electrostatic forces at room temperature. Our newly designed Ru(iii)-PEI@MWCNTs were employed as bifunctional catalysts for the NRR and 5-hydroxymethylfurfural (HMF) oxidation. At -0.10 V vs. the reversible hydrogen electrode (RHE), our Ru(iii)-PEI@MWCNTs exhibited the high NH₃ yield rate of 188.90 μg_NH3 mg_cat.^-1 h^-1 and the faradaic efficiency (FE) of 30.93% at room temperature. Furthermore, owing to its favorable thermodynamics for HMF oxidation, the Ru(iii)-PEI@MWCNT electrode demonstrated an impressive electrocatalytic HMF oxidation at 1.24 V, 220 mV lower than that for oxygen evolution. The two-electrode electrolyzer employing Ru(iii)-PEI@MWCNTs as a bifunctional catalyst for both the cathode and the anode showed the current density of 0.50 mA cm^-2 with the cell voltage of only 1.34 V over 27 hours of stable electrolysis with a 94% FE for 2,5-furandicarboxylic acid (FDCA) production; this suggested an outstanding performance of this electrolyzer for the coupling of NRR with HMF oxidation. This study represents the first attempt at the ground demonstration of combining NH₃ production with biomass upgrading.]]> Thu 07 Dec 2023 11:10:30 AEDT ]]> https://nova.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://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:46819 2⁻), hydrogen peroxide (H₂O₂), and hydroxyl radicals (•OH) via oxygen reduction reaction (ORR), by using Bi₄NbO₈X (X = Cl, Br) single crystalline nanoplates. Significantly, the piezo-photocatalytic process leads to the highest ORR performance of the Bi₄NbO₈Br nanoplates, exhibiting •O₂⁻, H₂O₂, and •OH evolution rates of 98.7, 792, and 33.2 µmol g⁻¹ h⁻¹, respectively. The formation of a polarized electric field and band bending allows directional separation of charge carriers, promoting the catalytic activity. Furthermore, the reductive active sites are found enriched on all the facets in the piezo–photocatalytic process, also contributing to the ORR. By piezo–photodeposition of Pt to artificially plant reductive reactive sites, the Bi₄NbO₈Br plates demonstrate largely enhanced photocatalytic H2 production activity with a rate of 203.7 µmol g⁻¹ h⁻¹. The present work advances piezo–photocatalysis as a new route for ROS generation, but also discloses the potential of piezo–photocatalytic active sites enriching for H₂ evolution.]]> Thu 01 Dec 2022 10:40:44 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:46850 2 photoreduction into solar fuels is promising for generating renewable energy. Herein, SrBi₂Nb₂O₉ nanosheets are prepared as high-performance photocatalysts for CO₂ reduction, highlighting superiority of ferroelectric polarization and anisotropic charge migration. Ferroelectric polarization within SrBi₂Nb₂O₉ nanosheets provides an in-built electric field, which greatly facilitates the bulk charge separation. Also, the photogenerated electrons and holes migrate separately to the NbO₆ octahedral layers and within the ab-plane in the Bi₂O₂ layers, achieving efficient anisotropic charge migration. Without co-catalyst or sacrificial agent, SrBi₂Nb₂O₉ nanosheets show outstanding CO₂ reduction activity in producing CH₄. The ferroelectric polarization is further enhanced by electric poling and annealing post-treatments. The electrically poled SrBi₂Nb₂O₉ shows a high CH₄ evolution rate of 25.91 μmol g⁻¹ h⁻¹ with an AQE of 1.96 % at 365 nm, exceeding most of state-of-the-art photocatalysts reported to date. This work paves an avenue for development of highly efficient photocatalysts and beyond by tuning the ferroelectricity and electronic structure.]]> Mon 29 Jan 2024 18:48:21 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:46331 Mon 29 Jan 2024 18:37:54 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:52716 Mon 29 Jan 2024 18:23:04 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:43276 Mon 29 Jan 2024 18:05:32 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:41303 Mon 29 Jan 2024 18:04:18 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:37374 1/2) of Gd₂O₃-Co/NG is 100 mV more positive than that of Co/NG and even close to commercial Pt/C. The density functional theory calculation and spectroscopic analysis demonstrate that, owing to intrinsic charge redistribution at the engineered interface of Gd₂O₃/Co, the coupled Gd₂O₃-Co can break the OOH*-OH* scaling relation and result in a good balance of OOH* and OH* binding on Gd₂O₃-Co surface. For practical application, a rechargeable Zn-air battery employing Gd₂O₃-Co/NG as an air-cathode achieves a large power density and excellent charge-discharge cycle stability.]]> Mon 29 Jan 2024 18:04:04 AEDT ]]> https://nova.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://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:44528 Mon 29 Jan 2024 17:54:37 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:40859 E_1/2) and a small ΔE (ΔE = E_j10 − E_1/2) of 0.73 V in an alkaline electrolyte, enabling its use as an outstanding cathode in rechargeable Zn−air batteries. In situ Raman spectra demonstrated that metal hydroxides formed during OER endowed the obtained electrocatalyst with a predominant catalytic performance. Impressively, a homemade rechargeable Zn− air battery composed by this nanocomposite as the cathode delivered remarkable properties with a peak power density of 137 mW cm⁻² and a high specific capacity of 829 mAh g⁻¹. The battery also demonstrated outstanding long-term stability with a well-maintained porous structure and crystal structure.]]> Mon 29 Jan 2024 17:51:48 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:46344 −1 mgCAT⁻¹ and faradaic efficiency (FE) of 11.6% are achieved using our antimonene nanosheets. Theoretical calculations suggest that the oxidized species of antimonene act as the active catalytic sites for the NRR process. This work opens up a new avenue towards the development of 2D electrocatalysts for clean energy.]]> Mon 29 Jan 2024 17:48:27 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:46662 3N₄) has attracted much attention due to its unique properties and excellent performance in the field of sensors, which has inspired the authors to compile this review. Although there are many reviews on the synthesis and applications of g‐C₃N₄ materials, a targeted, systematic, comprehensive summary of applications in sensors and the sensing mechanisms of g‐C₃N₄‐based nanomaterials are not published. In this review, the preparation methods and synthetic conditions for preparing g‐C₃N₄ with different morphologies, such as conventional bulk g‐C₃N₄, g‐C₃N₄ nanosheets, and g‐C₃N₄ quantum dots, are introduced in detail. By reviewing recent advances in g‐C₃N₄‐based nanomaterials in ion sensors, biosensors, gas sensors, and humidity sensors, this study provides more comprehensive and in‐depth information for the further design of g‐C₃N₄‐based sensors with enhanced performance. A brief outlook of g‐C3N4‐based sensors is presented as the conclusion of this review.]]> Mon 28 Nov 2022 18:25:37 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:40925 Mon 25 Jul 2022 15:11:17 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:36639 Mon 22 Jun 2020 13:20:40 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:35062 6+ doped Ni(OH)₂ nanosheet sample (w-Ni(OH)₂) with an outstanding oxygen evolution reaction (OER) performance that is, in a 1 M KOH medium, an overpotential of 237 mV is obtained reaching a current density of 10 mA/cm². Moreover, at high current density of 80 mA/cm², the overpotential value is 267 mV. The corresponding Tafel slope is measured to be 33 mV/dec. The d⁰ W⁶⁺ atom with a low spin-state has more outermost vacant orbitals, resulting in more water and OH- groups being adsorbed on the exposed W sites of the Ni(OH)₂ nanosheet. Density functional theory (DFT) calculations confirm that the O radical and O-O coupling are both generated at the same site of W⁶⁺. This work demonstrates that W⁶⁺ doping can promote the electrocatalytic water oxidation activity of Ni(OH)2 with the highest performance.]]> Mon 19 Aug 2019 16:37:22 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:35061 2, respectively, in 0.5 M H₂SO₄ solution with a small Tafel slope of 43 mV/dec. Thus it outperforms many of the state-of-art molybdenum-based hydrogen evolution catalysts reported to date.]]> Mon 17 Jun 2019 12:09:40 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:37255 cat.⁻¹, Faradaic efficiency: 30.1%) at the low overpotential, and to display a high chemical stability and sustained catalytic performance. In conjunction, further mechanism studies indicate B and Al as main-group metals show a highly selective affinity to N₂ due to the strong interaction between the B 2p/Al 3p band and the N 2p orbitals, while Mo exhibits specific catalytic activity toward the subsequent reduction reaction. Overall, the MAB-phase catalyst under the synergy of the elements within ternary compound can suppress the hydrogen evolution reaction and achieve enhanced NRR performance. The significance of this work is to provide a promising candidate in the future synthesis of ammonia.]]> Mon 14 Nov 2022 20:44:46 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:31930 Mon 09 Apr 2018 09:26:09 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:34851 4Ti₄O₁₅ as a robust photocatalyst for efficient CO₂ reduction. In the absence of co-catalysts and sacrificial agents, the annealed SrBi₄Ti₄O₁₅ nanosheets with the strongest ferroelectricity cast a prominent photocatalytic CO₂ reduction activity for CH₄ evolution with a rate of 19.8 μmol h⁻¹ g⁻¹ in the gas-solid reaction system, achieving an apparent quantum yield (AQY) of 1.33% at 365 nm, outperforming most of the reported photocatalysts. The ferroelectric hysteresis loop, piezoresponse force microscopy (PFM) and ns-level time-resolved fluorescence spectra uncover that the outstanding CO₂ photoreduction activity of SrBi₄Ti₄O₁₅ mainly stems from the strong ferroelectric spontaneous polarization along [100] direction, which allows efficient bulk charge separation along opposite direction. DFT calculations also disclose that both electrons and holes show the smallest effective masses along a axis, verifying the high mobility of charge carriers facilitated by ferroelectric polarization. This study suggests that the traditionally semiconducting ferroelectric materials that have long been studied as ferro/piezoelectric ceramics now may be powerfully applied in the photocatalytic field to deal with the growing energy crisis.]]> Mon 08 Nov 2021 09:54:09 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:40875 µmol/g·h, which is approximately 14 times higher than that of the bare am@TiO₂. Moreover, an apparent quantum yield (AQY) of 18.99% is obtained under LED-405 illumination. This work provides a direction for improving the photocatalytic performance and helps to gain a fundamental understanding of the water oxidation steps.]]> Mon 08 Aug 2022 15:49:38 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:36540 Mon 01 Jun 2020 12:07:38 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:41276 2 have been successfully stabilized and uniformly distributed on the surface of n-butyl triethyl ammonium bromide functionalized polypyrrole/graphene oxide (BTAB/PPy/GO) by a very simple hydrothermal method. BTAB as a typical kind of quaternary ammonium-type ionic liquids (ILs) played a crucial role in the formation of the obtained 1T-MoS₂/BTAB/PPy/GO. It was covalently linked with PPy/GO and arranged in a highly ordered order at the solid–liquid interface of PPy/GO and H₂O due to Coulombic interactions and other intermolecular interactions, which would induce and stabilize ultrathin 1T-MoS₂ nanoplates by morphosynthesis. The good electrocatalytic activity toward nitrogen reduction reaction (NRR) with strong durability and good stability can be achieved by 1T-MoS₂/BTAB/PPy/GO due to their excellent inorganic/organic hierarchical lamellar micro-/nanostructures. Especially, after the long-term electrocatalysis for NRR at a negative potential, metastable 1T-MoS2 as the catalytic center undergoes two types of irreversible crystal phase transition, which was converted to 1T′-MoS₂ and Mo₂N, caused by the competitive hydrogen evolution reaction (HER) process and the electrochemical reaction between the electroactive 1T-MoS₂ and N₂, respectively. The new N–Mo bonding prevents Mo atoms from binding to other N atoms in N₂, resulting in the deactivation of the electrocatalysts to NRR after being used for 18 h. Even so, quaternary ammonium-type ILs would induce the crystal structures of transition-metal dichalcogenides (TMDCs), which might provide a new thought for the reasonable design of electrocatalysts based on TMDCs for electrocatalysis.]]> Mon 01 Aug 2022 10:10:30 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:41229 3 yield: 10.6 μg h^–1 cm^–2 mg_cat.^–1 and Faradaic efficiency: 22.6%) at a low overpotential (177 mV). Investigation indicates that the catalyst shows excellent N₂-selective captures due to the unsaturated metal sites binding with N₂. More specifically, as the Al 3p band can strongly interact with N 2p orbitals, Al as a main group metal presents a high and selective affinity to N₂. The utilization of multifunctional MOF catalysts delivers both high N₂ selectivity and abundant catalytic sites, resulting in remarkable efficiency for NH₃ production.]]> Fri 29 Jul 2022 11:49:26 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:44274 2Bi₂Nb₂TiO₁₂ nanosheets, which were prepared by a mineralizer‐assisted soft‐chemical method. Introduction of OVs on the surface of Sr₂Bi₂Nb₂TiO₁₂ extends photoresponse to cover the whole visible region and also tremendously promotes separation of photoinduced charge carriers. Adsorption and activation of CO₂ molecules on the surface of the catalyst are greatly enhanced. In the gas‐solid reaction system without co‐catalysts or sacrificial agents, OVs‐abundant Sr₂Bi₂Nb₂TiO₁₂ nanosheets show outstanding CO₂ photoreduction activity, producing CO with a rate of 17.11 μmol g⁻¹ h⁻¹, about 58 times higher than that of the bulk counterpart, surpassing most previously reported state‐of‐the‐art photocatalysts. Our study provides a three‐in‐one integrated solution to advance the performance of photocatalysts for solar‐energy conversion and generation of renewable energy.]]> Fri 23 Jun 2023 09:56:26 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:41162 Fri 23 Feb 2024 10:25:52 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:40091 2 photoreduction by coupling macroscopic spontaneous polarization and surface oxygen vacancies (OVs) of BiOIO₃ single crystals is reported. The oriented growth of BiOIO₃ single-crystal nanostrips along the [001] direction, ensuing substantial well-aligned IO₃ polar units, renders a large enhancement for the macroscopic polarization electric field, which is capable of driving the rapid separation and migration of charges from bulk to surface. Meanwhile the introduction of surface OVs establishes a local electric field for charge migration to catalytic sites on the surface of BiOIO₃ nanostrips. Highly polarized BiOIO₃ nanostrips with ample OVs demonstrate outstanding CO₂ reduction activity for CO production with a rate of 17.33 μmol g^-1 h^-1 (approximately ten times enhancement) without any sacrificial agents or cocatalysts, being one of the best CO₂ reduction photocatalysts in the gas-solid system reported so far. This work provides an integrated solution to governing charge movement behavior on the basis of collaborative polarization from bulk and surface.]]> Fri 22 Jul 2022 13:41:21 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:39855 6 cluster and different groups-decorated V-shaped ligands (H₂L), are successfully synthesized through a facile ligand functionalization method. Subsequently, three isostructural Zr-MOFs, including the parent structure Zr(H₂L), amino-decorated Zr(H₂L) (NH₂-Zr(H₂L)), and fluorine and amino bi-decorated Zr(H₂L) (F-NH₂-Zr(H₂L)), are employed as the platform for systematically investigating the effect of Lewis basic groups on the CO₂ adsorption and separation behavior, more importantly the CO₂ chemical fixation. Benefitting from the decorated Lewis basic groups, not only the CO₂ adsorption enthalpy and selectivity over CH₄ of NH₂-Zr(H₂L) and F-NH₂-Zr(H₂L) are improved, but also their catalytic activities for cycloaddition of CO₂ to form cyclic carbonates are significantly enhanced. Among them, F-NH₂-Zr(H₂L) exhibits the most effective performance for cycloaddition of CO₂ and styrene epoxide, which can be attributed to the strong polarization between the CO₂ molecule and the framework of F-NH₂-Zr(H₂L). Under a mild condition, the yield of F-NH₂-Zr(H₂L) for cycloaddition of CO₂ with styrene epoxide can reach up to 97%, which surpasses most of the reported MOFs-based catalysts.]]> Fri 22 Jul 2022 13:20:26 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:35911 420 nm), and the H₂ evolution rate is 6.9 and 67.2 times higher than those of bare g-C₃N₄ and Bi₄NbO₈Cl, respectively. The stronger photoabsorption of g-C₃N₄/Bi₄NbO₈Cl (beyond 500 nm) allows generation of more photons than does g-C₃N₄. More importantly, the separation and transfer of photoexcited charge carriers were greatly improved between g-C₃N₄ and Bi₄NbO₈Cl, as revealed by the photoelectrochemical and time-resolved photoluminescence decay results. The Z-scheme charge transfer mechanism of g-C₃N₄/Bi₄NbO₈Cl was also manifested by electron spin resonance (ESR). The work furnishes a new solution to fabrication of high-efficiency Z-scheme catalysts for countering energy issues.]]> Fri 17 Jan 2020 16:37:49 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:38932 -2, a small Tafel slope of 87 mV dec^-1 and prominent durability. Percolation theory was for the first time introduced to interpret the catalytic mechanism of the CD/CF catalysts. The special morphology assembled by the 0D carbons constituted the percolating clusters and promoted electron transport throughout the 1D carbons. The strategy and theory can be adapted to general electrocatalytic applications for achieving and interpreting precise tuning on highly efficient electron transfer in electrocatalysts.]]> Fri 15 Sep 2023 15:54:21 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:52063 2 hierarchical nanotubes with high pre-intercalated K cation content (a-K_0.19MnO₂) are proposed as a superior cathode for ZIBs. Specifically, the a-K_0.19MnO₂ nanotubes are prepared via a self-sacrificial template method, including a neutral solvent hydrothermal intercalation and a subsequent annealing phase transformation process. When tested as cathodes for ZIBs, a subsequent H⁺ and Zn²⁺intercalation mechanism at different voltage platforms is clarified. The water-solvated H⁺ first inserts into tunnel cavities and the subsequent insertion of Zn²⁺ into MnO₂ partially changes the MnO₂ phase from a tunnel-type structure to a layered-type structure (Zn-buserite). The high content pre-intercalated K cations in the layered-type matrix as pillars stabilize the layered structures and expand Zn²⁺ migration channels, which can facilitate the diffusion of Zn2⁺ in the MnO₂ cathodes. It is noteworthy that, a K-salt additive is employed to maintain the concentration of K⁺ in the electrolyte with the aim of inhibiting the extraction of K⁺ from the a-K_0.19MnO₂ host material during cycling, thereby further boosting the cycling ability.]]> Fri 13 Oct 2023 08:36:57 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:41820 Fri 12 Aug 2022 12:52:30 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:46095 Fri 11 Nov 2022 11:03:01 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:46953 Fri 09 Dec 2022 15:31:44 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:38173 2(NO₃)₂ (HPU-10) (H₂L = 2,6-bis-(5-pyridin-4-yl-1H-[1,2,4]triazol-3-yl)- pyridine), and demonstrate that this novel chemosensor has the property of ratiometric detection of Zn2+ and Cd2+. The detection limit of HPU-10 sensing Zn²⁺ and Cd²⁺ is 0.319 and 0.965 μM, respectively. The sensing mechanism can be explained by (i) the decomposition of HPU-10 and (ii) the recombination of Zn²⁺ or Cd²⁺ with ligand forming 2HL^--Zn²⁺ or 2HL^--Cd²⁺, respectively. Moreover, the fluorescent sensor HPU-10 can detect the nitroaromatic compound 2, 4-DNP via a fluorescence quenching mechanism. The detection limits obtained from linear regression curve plots of 2, 4-DNP is calculated to be 1.69 μM. In addition, the possible use of the probe coated paper for tracing the target analytes has also been presented.]]> Fri 06 Aug 2021 13:39:40 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:36381 2 , which was attributed to the high reactivity and stability of isolated single Co atoms. Our findings open up a new avenue to regulate the metal particle size and catalytic performance of MOF derivatives.]]> Fri 03 Apr 2020 16:59:31 AEDT ]]>