https://ogma.newcastle.edu.au/vital/access/ /manager/Index en-au 5 https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:4841 Wed 11 Apr 2018 14:05:14 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:7831 Wed 11 Apr 2018 13:53:53 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:17629 Wed 11 Apr 2018 11:37:39 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:45435 2O₃ catalyst for the hydrogenation of carbon oxides, in the presence of light hydrocarbons, was studied. Ni/Al₂O₃ displayed a high activity for the complete conversion of CO and CO₂ to methane and C₂₊ hydrocarbons. Moreover, over a discrete and relatively narrow temperature range, the net concentration of light C₂₊ hydrocarbons was elevated, with the exit stream containing a higher concentration of C₂₊ species than was present in the feed stream and the product stream being virtually free of carbon oxides. It is found that the addition of manganese can enhance the selectivity toward the production of light hydrocarbons. A series of Ni–Mn/Al₂O₃ catalysts, prepared with different Ni/Mn ratios, were studied. Various characterization techniques such as X-ray diffraction (XRD) analysis, CO and H₂ chemisorption, in situ nitric oxide adsorption Fourier transform infrared spectroscopy (NO-FTIR), and temperature-programmed reduction (TPR) were performed to gain an insight into how the addition of Mn to the primary catalyst enhances the yield of light hydrocarbons. The origin of Mn promotion was demonstrated through density functional theory (DFT) calculations, which revealed the favorable Mn substitution at the Ni(211) step edge sites under reducing conditions. The affinity of these Mn species toward oxidation stabilizes the CO dissociation product and thus provides a thermodynamic driving force that promotes C–O bond cleavage compared to the Mn-unmodified catalyst surface.]]> Wed 07 Feb 2024 15:34:43 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:36086 Wed 05 Feb 2020 14:51:11 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:54340 Tue 20 Feb 2024 16:12:26 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:47138 Tue 14 Nov 2023 11:38:41 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:38788 Tue 01 Feb 2022 12:17:25 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:10230 Sat 24 Mar 2018 08:11:27 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:16939 2Ni surface–sandwich ordering at the nanoscale. These findings open up a range of opportunities for the synthesis of new kinds of Pd-Ni nanostructures such as a five-layer Pd₂Ni nanofilm from which a Pd₂Ni nanotube might be fabricated. In this paper, we report on an ab initio spatial optimization and structural energy calculation of a five-layer Pd₂Ni nanofilm, which are performed using plane-wave pseudopotential total energy calculations in the generalized gradient approximation of density functional theory. The results of the ab-initio calculations show that the five-layer Pd₂Ni nanofilm is structurally stable and its energy is ~0.4 eV higher than the energy of a bulk crystal alloy having the same composition.]]> Sat 24 Mar 2018 07:51:50 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:5509 Sat 24 Mar 2018 07:46:43 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:26345 Sat 24 Mar 2018 07:35:51 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:26722 Sat 24 Mar 2018 07:26:21 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:3299 Sat 24 Mar 2018 07:22:24 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:3217 Sat 24 Mar 2018 07:22:13 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:23579 Sat 24 Mar 2018 07:12:44 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:24746 PhDPB^Ph)Ni. There are four typical H₂ activation modes for LA-TM bifunctional catalysts: (1) the cis homolytic mode, (2) the trans homolytic mode, (3) the synergetic heterolytic mode, and (4) the dissociative heterolytic mode. The feature of each activation mode has been characterized by key transition state structures and natural bond orbital analysis. Among these four typical modes, (^PhDPB^Ph)Ni catalyst most prefers the synergetic heterolytic mode (ΔG‡ = 29.7 kcal/mol); however the cis homolytic mode cannot be totally disregarded (ΔG‡ = 33.7 kcal/mol). In contrast, the trans homolytic mode and dissociative heterolytic mode are less feasible (ΔG‡ = ∼42 kcal/mol). The general mechanistic picture presented here is fundamentally important for the development and rational design of LA-TM catalysts in the future.]]> Sat 24 Mar 2018 07:11:02 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:36398 Mon 04 May 2020 13:53:00 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:17273 Fri 10 Nov 2023 16:00:41 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:53581 Fri 08 Dec 2023 15:48:29 AEDT ]]>