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Full-Text Articles in Engineering

Periodic Deprivation Of Gaseous Hydrogen Sulfide Affects The Activity Of The Concrete Corrosion Layer In Sewers, Xiaoyan Sun, Guangming Jiang, Philip Bond, Jurg Keller Jan 2019

Periodic Deprivation Of Gaseous Hydrogen Sulfide Affects The Activity Of The Concrete Corrosion Layer In Sewers, Xiaoyan Sun, Guangming Jiang, Philip Bond, Jurg Keller

Faculty of Engineering and Information Sciences - Papers: Part B

Sulfide induced concrete corrosion significantly reduces the service life of the sewer systems. Gaseoushydrogen sulfide (H2S) levels are a key factor affecting the corrosion rate and thesefluctuate due to thediurnalflow pattern of sewers. Currently, there is little known about how suchfluctuations, in particularthe periodic deprivation of H2S, may affect the corrosion activity. This study investigated the impact ofthe deprivation of H2S on the sulfide uptake rate (SUR) of concrete coupons incubated in laboratorycorrosion chambers. After systematic evaluation of the gaseous H2S concentration profiles of two sewersystems, two types of profiles, i.e. short- (1 h) and long- (12 h) term deprivation …


Designed Conducting Polymer Composites That Facilitate Long-Lived, Light-Driven Oxygen And Hydrogen Evolution From Water In A Photoelectrochemical Concentration Cell (Pecc), Mohammed Alsultan, Khalid Zainulabdeen, Pawel W. Wagner, Gerhard F. Swiegers, Holly Warren Jan 2019

Designed Conducting Polymer Composites That Facilitate Long-Lived, Light-Driven Oxygen And Hydrogen Evolution From Water In A Photoelectrochemical Concentration Cell (Pecc), Mohammed Alsultan, Khalid Zainulabdeen, Pawel W. Wagner, Gerhard F. Swiegers, Holly Warren

Australian Institute for Innovative Materials - Papers

Light-driven water-splitting to generate hydrogen and oxygen from water is typically carried out in an electrochemical cell with an external voltage greater than 1.23 V applied between the electrodes. In this work, we examined the use of a concentration/chemical bias as a means of facilitating water-splitting under light illumination without the need for such an externally applied voltage. Such a concentration bias was created by employing a pH differential in the liquid electrolytes within the O2-generating anode half-cell and the H2-generating cathode half-cell. A novel, stretchable, highly ion-conductive polyacrylamide CsCl hydrogel was developed to connect the two half-cells. The key …


Electrocatalytically Inactive Sns2 Promotes Water Adsorption/Dissociation On Molybdenum Dichalcogenides For Accelerated Alkaline Hydrogen Evolution, Yaping Chen, Xingyong Wang, Mengmeng Lao, Kun Rui, Xiaobo Zheng, Haibo Yu, Jing Ma, Shi Xue Dou, Wenping Sun Jan 2019

Electrocatalytically Inactive Sns2 Promotes Water Adsorption/Dissociation On Molybdenum Dichalcogenides For Accelerated Alkaline Hydrogen Evolution, Yaping Chen, Xingyong Wang, Mengmeng Lao, Kun Rui, Xiaobo Zheng, Haibo Yu, Jing Ma, Shi Xue Dou, Wenping Sun

Australian Institute for Innovative Materials - Papers

Molybdenum dichalcogenides, in particular, MoS2 and MoSe2, are very promising nonprecious metal-based electrocatalysts for hydrogen evolution reaction (HER) in acidic media. They exhibit inferior alkaline HER activity, however, due to the sluggish water dissociation process. Here, we design and synthesize new molybdenum dichalcogenide-based heterostructures with the basal planes decorated with SnS2 quantum dots towards enhanced alkaline HER activity. The electrochemical results reveal that the alkaline hydrogen evolution kinetics of molybdenum dichalcogenides is substantially accelerated after incorporation of SnS2 quantum dots. The optimal MoSe2/SnS2 heterostructure delivers a much lower overpotential of 285 mV than MoSe2 (367 mV) to reach a current …


Effect Of Storage Environment On Hydrogen Generation By The Reaction Of Al With Water, Yin-Qiang Wang, Wei-Zhuo Gai, Xia-Yu Zhang, Hong-Yi Pan, Zhenxiang Cheng, Pingguang Xu, Zhen-Yan Deng Jan 2017

Effect Of Storage Environment On Hydrogen Generation By The Reaction Of Al With Water, Yin-Qiang Wang, Wei-Zhuo Gai, Xia-Yu Zhang, Hong-Yi Pan, Zhenxiang Cheng, Pingguang Xu, Zhen-Yan Deng

Australian Institute for Innovative Materials - Papers

Al powder was stored in saturated water vapor, oxygen, nitrogen and drying air separately for a time period of up to six months, the degradation behavior of Al activity was characterized by the reaction of Al with water. It was found that water vapor decreased the induction time for the beginning of Al-water reaction and reduced the total hydrogen generation per unit weight of Al, while oxygen increased the induction time and retarded the Al-water reaction. In contrast, the effect of nitrogen and drying air on Al activity was weak. The mechanism analyses indicated that water vapor promoted the hydration …


Oxygen-Free Layer-By-Layer Assembly Of Lithiated Composites On Graphene For Advanced Hydrogen Storage, Guanglin Xia, Yingbin Tan, Xiaowei Chen, Fang Fang, Dalin Sun, Xingguo Li, Zaiping Guo, Xuebin Yu Jan 2016

Oxygen-Free Layer-By-Layer Assembly Of Lithiated Composites On Graphene For Advanced Hydrogen Storage, Guanglin Xia, Yingbin Tan, Xiaowei Chen, Fang Fang, Dalin Sun, Xingguo Li, Zaiping Guo, Xuebin Yu

Australian Institute for Innovative Materials - Papers

A facile hydrogenation-induced self-assembly strategy to synthesize lithium hydride (LiH) nanosheets with a thickness of 2 nm that are uniformly distributed on graphene is reported and designed. Taking advantage of LiH nanosheets with high reactivity and a homogeneous distribution on graphene support as a nanoreactor, the confined chemical synthesis of oxygen-free lithiated composites is effectively and efficiently realized.


Reduction Of Quartz To Silicon Monoxide By Methane-Hydrogen Mixtures, Xiang Li, Guangqing Zhang, Ragnar Tronstad, Oleg Ostrovski Jan 2016

Reduction Of Quartz To Silicon Monoxide By Methane-Hydrogen Mixtures, Xiang Li, Guangqing Zhang, Ragnar Tronstad, Oleg Ostrovski

Faculty of Engineering and Information Sciences - Papers: Part A

The reduction of quartz was studied isothermally in a fluidized bed reactor using continuously flowing methane-hydrogen gas mixture in the temperature range from 1623 K to 1773 K (1350 °C to 1500 °C). The CO content in the off-gas was measured online using an infrared gas analyzer. The main phases of the reduced samples identified by XRD analysis were quartz and cristobalite. Significant weight loss in the reduction process indicated that the reduction products were SiO and CO. Reduction of SiO2 to SiO by methane starts with adsorption and dissociation of CH4 on the silica surface. The high carbon activity …


Graphene-Wrapped Reversible Reaction For Advanced Hydrogen Storage, Guanglin Xia, Yingbin Tan, Feilong Wu, Fang Fang, Dalin Sun, Zaiping Guo, Zhenguo Huang, Xuebin Yu Jan 2016

Graphene-Wrapped Reversible Reaction For Advanced Hydrogen Storage, Guanglin Xia, Yingbin Tan, Feilong Wu, Fang Fang, Dalin Sun, Zaiping Guo, Zhenguo Huang, Xuebin Yu

Australian Institute for Innovative Materials - Papers

Here, we report the fabrication of a graphene-wrapped nanostructured reactive hydride composite, i.e., 2LiBH4-MgH2, made by adopting graphene-supported MgH2 nanoparticles (NPs) as the nanoreactor and heterogeneous nucleation sites. The porous structure, uniform distribution of MgH2 NPs, and the steric confinement by flexible graphene induced a homogeneous distribution of 2LiBH4-MgH2 nanocomposite on graphene with extremely high loading capacity (80 wt%) and energy density. The well-defined structural features, including even distribution, uniform particle size, excellent thermal stability, and robust architecture endow this composite with significant improvements in its hydrogen storage performance. For instance, at a temperature as low as 350 °C, a …


Manipulating Coupling State And Magnetism Of Mn-Doped Zno Nanocrystals By Changing The Coordination Environment Of Mn Via Hydrogen Annealing, Yan Cheng, W Li, Weichang Hao, Huaizhe Xu, Zhongfei Xu, Li Rong Zheng, Jing Zhang, S X. Dou, Tianmin Wang Jan 2016

Manipulating Coupling State And Magnetism Of Mn-Doped Zno Nanocrystals By Changing The Coordination Environment Of Mn Via Hydrogen Annealing, Yan Cheng, W Li, Weichang Hao, Huaizhe Xu, Zhongfei Xu, Li Rong Zheng, Jing Zhang, S X. Dou, Tianmin Wang

Australian Institute for Innovative Materials - Papers

Mn-doped ZnO nanocrystals are synthesized by a wet chemical route and treated in H2/Ar atmosphere with different H2/Ar ratios. It is found that hydrogen annealing could change the coordination environment of Mn in ZnO lattice and manipulate the magnetic properties of Mn-doped ZnO. Mn ions initially enter into interstitial sites and a Mn3+O6 octahedral coordination is produced in the prepared Mn-doped ZnO sample, in which the nearest neighbor Mn3+ and O2 ions could form a Mn3+-O2--Mn3+ complex. After H2 annealing, interstitial Mn ions can substitute for Zn to generate the Mn2+O4 tetrahedral coordination in the nanocrystals, in which neighboring Mn2+ …


3d Binder-Free Mose2 Nanosheets/Carbon Cloth Electrodes For Efficient And Stable Hydrogen Evolution Prepared By Simple Electrophoresis Deposition Strategy, Yundan Liu, Long Ren, Zhen Zhang, Xiang Qi, Hongxing Li, Jianxin Zhong Jan 2016

3d Binder-Free Mose2 Nanosheets/Carbon Cloth Electrodes For Efficient And Stable Hydrogen Evolution Prepared By Simple Electrophoresis Deposition Strategy, Yundan Liu, Long Ren, Zhen Zhang, Xiang Qi, Hongxing Li, Jianxin Zhong

Australian Institute for Innovative Materials - Papers

We successfully developed a simple electrophoretic deposition (EPD) method to decorate the MoSe2 nanosheets on the carbon fiber surface of carbon cloth (MoSe2/CC). With this process, MoSe2 nanosheets can be uniformly and tightly deposited on this flexible conductor to form a 3D binder-free electrode for hydrogen evolution reaction (HER). The film thickness can also be controlled by the EPD time. Directly used as binder-free electrodes for hydrogen evolution reaction, the as-prepared 3D MoSe2/CC samples exhibit excellent catalytic activity in an acidic electrolyte (21 mA/cm2 at an over-potential of 250 mV). Variation of MoSe2 nanosheets film thickness in the electrodes could …


Carbothermal Reduction Of Quartz In Methane-Hydrogen-Argon Gas Mixture, Xiang Li, Guangqing Zhang, Kai Tang, Oleg Ostrovski, Ragnar Tronstad Jan 2015

Carbothermal Reduction Of Quartz In Methane-Hydrogen-Argon Gas Mixture, Xiang Li, Guangqing Zhang, Kai Tang, Oleg Ostrovski, Ragnar Tronstad

Faculty of Engineering and Information Sciences - Papers: Part A

Synthesis of silicon carbide (SiC) by carbothermal reduction of quartz in a CH4-H2-Ar gas mixture was investigated in a laboratory fixed-bed reactor in the temperature range of 1573 K to 1823 K (1300 °C to 1550 °C). The reduction process was monitored by an infrared gas analyser, and the reduction products were characterized by LECO, XRD, and SEM. A mixture of quartz-graphite powders with C/SiO2 molar ratio of 2 was pressed into pellets and used for reduction experiments. The reduction was completed within 2 hours under the conditions of temperature at or above 1773 K (1500 °C), methane content of …


Guanidinium Octahydrotriborate: An Ionic Liquid With High Hydrogen Storage Capacity, Weidong Chen, Zhenguo Huang, Guotao Wu, Teng He, Zhao Li, Juner Chen, Zaiping Guo, Hua-Kun Liu, Ping Chen Jan 2015

Guanidinium Octahydrotriborate: An Ionic Liquid With High Hydrogen Storage Capacity, Weidong Chen, Zhenguo Huang, Guotao Wu, Teng He, Zhao Li, Juner Chen, Zaiping Guo, Hua-Kun Liu, Ping Chen

Australian Institute for Innovative Materials - Papers

For chemical hydrogen storage, capacity is one key criterion that has spurred intense efforts to investigate compounds with high hydrogen content. The guanidinium cation and the octahydrotriborate anion possess 6 H+ and 8 H-, respectively. The combination of these two ions yields guanidinium octahydrotriborate with 13.8 wt% hydrogen. This paper presents its facile synthesis, as confirmed by 11B and 1H nuclear magnetic resonance spectroscopy. The results show that guanidinium octahydrotriborate is an ionic liquid with a melting point below -10°C, which makes it a possible injectable/pumpable hydrogen carrier. It decomposes selectively to hydrogen, in stark …


Hierarchical Porous Li 2 Mg(Nh)2@C Nanowires With Long Cycle Life Towards Stable Hydrogen Storage, Guanglin Xia, Yingbin Tan, Dan Li, Zaiping Guo, Hua-Kun Liu, Zongwen Liu, Xuebin Yu Jan 2014

Hierarchical Porous Li 2 Mg(Nh)2@C Nanowires With Long Cycle Life Towards Stable Hydrogen Storage, Guanglin Xia, Yingbin Tan, Dan Li, Zaiping Guo, Hua-Kun Liu, Zongwen Liu, Xuebin Yu

Australian Institute for Innovative Materials - Papers

The hierarchical porous Li2Mg(NH)2@C nanowires full of micropores, mesopores, and macropores are successfully fabricated via a single-nozzle electrospinning technique combined with in-situ reaction between the precursors, i.e., MgCl2 and LiN3, under physical restriction upon thermal annealing. The explosive decomposition of LiN3 well dispersed in the electrospun nanowires during carbothermal treatment induces a highly porous structure, which provides a favourable way for H2 delivering in and out of Li2Mg(NH)2 nanoparticles simultaneously realized by the space-confinement of the porous carbon coating. As a result, the thus-fabricated Li2Mg(NH)2 …


Effects Of Tungsten On The Hydrogen Embrittlement Behaviour Of Microalloyed Steels, Jingwei Zhao, Zhengyi Jiang, Chong Soo Lee Jan 2014

Effects Of Tungsten On The Hydrogen Embrittlement Behaviour Of Microalloyed Steels, Jingwei Zhao, Zhengyi Jiang, Chong Soo Lee

Faculty of Engineering and Information Sciences - Papers: Part A

The effects of tungsten (W) additions (0, 0.1, 0.5 and 1 wt.%) on the hydrogen embrittlement behaviour of microalloyed steels were systematically investigated by means of slow strain rate tests on circumferentially notched cylindrical specimens, and the mechanism of hydrogen-induced embrittlement was discussed. W addition is found to increase the activation energy of hydrogen desorption. Microstructural features affect the hydrogen embrittlement behaviour and fracture modes of microalloyed steels. It is suggested that the hydrogen-induced embrittlement in the studied microalloyed steels with different W additions is caused by the combined effects of decohesion and internal pressure in the presence of hydrogen.


Role Of Microstructure In Susceptibility To Hydrogen Embrittlement Of X70 Microalloyed Steel, Daniel Hejazi, Ahmed Saleh, Ayesha Haq, Druce Dunne, Andrzej Calka, Azdiar A. Gazder, Elena V. Pereloma Jan 2014

Role Of Microstructure In Susceptibility To Hydrogen Embrittlement Of X70 Microalloyed Steel, Daniel Hejazi, Ahmed Saleh, Ayesha Haq, Druce Dunne, Andrzej Calka, Azdiar A. Gazder, Elena V. Pereloma

Faculty of Engineering and Information Sciences - Papers: Part A

The effect of phases and steel processing on hydrogen uptake (diffusible and residual), surface and internal damage were evaluated using optical and scanning electron microscopy. The results have shown the fastest formation of blisters in ferrite-pearlite microstructure of strip, followed by equaixed ferrite-pearlite microstructure in normalised condition, then by ferrite-bainite microstructure. No blistering was observed in heat affected zone samples for up to 24 hrs charging. Analysis of hydrogen-induced cracking using electron back scattering diffraction has revealed that crack propagation has predominantly intragranular character without a clear preference on {001}, {110}, {112} and {123} planes and is independent of the …


Effects Of Hydrogen On The Critical Conditions For Dynamic Recrystallization Of Titanium Alloy During Hot Deformation, Jingwei Zhao, Hua Ding, Zhengyi Jiang, Dongbin Wei, Kezhi Linghu Jan 2014

Effects Of Hydrogen On The Critical Conditions For Dynamic Recrystallization Of Titanium Alloy During Hot Deformation, Jingwei Zhao, Hua Ding, Zhengyi Jiang, Dongbin Wei, Kezhi Linghu

Faculty of Engineering and Information Sciences - Papers: Part A

Hot deformation tests were performed to study the flow behavior and microstructural evolution of a Ti600 titanium alloy with different hydrogen contents. The effects of hydrogen on the critical conditions for the initiation of dynamic recrystallization (DRX) were investigated. The DRX kinetics models of hydrogenated Ti600 alloy were developed, and the DRX volume fractions were quantified under different deformation conditions. The results indicate that the addition of proper hydrogen (no greater than 0.3 pct) benefits the decrease of both the critical stress and critical strain for the initiation of DRX. The critical stress and critical strain are dependent linearly on …


Effect Of Microstructure And Composition On Hydrogen Permeation In X70 Pipeline Steels, Ayesha J. Haq, K Muzaka, D P. Dunne, A Calka, E V. Pereloma Jan 2013

Effect Of Microstructure And Composition On Hydrogen Permeation In X70 Pipeline Steels, Ayesha J. Haq, K Muzaka, D P. Dunne, A Calka, E V. Pereloma

Faculty of Engineering and Information Sciences - Papers: Part A

The influence of microstructure and composition on permeation of hydrogen in 1.2 and 0.5 wt.% Mn X70 pipeline steels after different processing was investigated using an electrochemical permeation technique. For 1.2 wt.% Mn (standard Mn) steel, the microstructure of normalised transfer bar was coarse equiaxed ferrite grains. This sample exhibited the highest diffusivity, followed by transfer bar, with a mixed ferriteebainitic ferrite microstructure; and hot rolled strip, with fine elongated ferrite grains. The 0.5 wt.% Mn (medium Mn) strip displayed lower diffusivity than the 1.2 wt.% Mn strip, due to hydrogen trapping by finer ferrite grains and a higher density …


Mixed-Metal (Li, Al) Amidoborane: Synthesis And Enhanced Hydrogen Storage Properties, Guanglin Xia, Yingbin Tan, Xiaowei Chen, Zaiping Guo, Hua-Kun Liu, Xuebin Yu Jan 2013

Mixed-Metal (Li, Al) Amidoborane: Synthesis And Enhanced Hydrogen Storage Properties, Guanglin Xia, Yingbin Tan, Xiaowei Chen, Zaiping Guo, Hua-Kun Liu, Xuebin Yu

Faculty of Engineering and Information Sciences - Papers: Part A

Mixed-metal (Li, Al) amidoborane has been synthesized via mechanical ball milling of ammonia borane with lithium hexahydridoaluminate in different molar ratios. The reversible dehydrogenation properties of the thus-synthesized metallic amidoborane and its mixtures with ammonia borane in different ratios were systematically investigated in comparison with neat ammonia borane (AB). On the basis of thermogravimetric analysis and mass spectrometry results, the thus-synthesized mixed-metal amidoborane was shown to release around 10 wt% hydrogen below 200 degrees C, with an effective suppression of volatile side products. Furthermore, a synergistic effect between metallic amidoborane and ammonia borane has been identified, which leads to the …


Unidirectional Suppression Of Hydrogen Oxidation On Oxidized Platinum Clusters, Yu Li, Jun Xing, Zong Chen, Zhen Li, Feng Tian, Li Zheng, Hai Wang, P Hu, Huijun Zhao, Huagui Yang Jan 2013

Unidirectional Suppression Of Hydrogen Oxidation On Oxidized Platinum Clusters, Yu Li, Jun Xing, Zong Chen, Zhen Li, Feng Tian, Li Zheng, Hai Wang, P Hu, Huijun Zhao, Huagui Yang

Australian Institute for Innovative Materials - Papers

Solar-driven water splitting to produce hydrogen may be an ideal solution for global energy and environment issues. Among the various photocatalytic systems, platinum has been widely used to co-catalyse the reduction of protons in water for hydrogen evolution. However, the undesirable hydrogen oxidation reaction can also be readily catalysed by metallic platinum, which limits the solar energy conversion efficiency in artificial photosynthesis. Here we report that the unidirectional suppression of hydrogen oxidation in photocatalytic water splitting can be fulfilled by controlling the valence state of platinum; this platinum-based cocatalyst in a higher oxidation state can act as an efficient hydrogen …


An Overview - Functional Nanomaterials For Lithium Rechargeable Batteries, Supercapacitors, Hydrogen Storage, And Fuel Cells, Hua-Kun Liu Jan 2013

An Overview - Functional Nanomaterials For Lithium Rechargeable Batteries, Supercapacitors, Hydrogen Storage, And Fuel Cells, Hua-Kun Liu

Australian Institute for Innovative Materials - Papers

There is tremendous worldwide interest in functional nanostructured materials, which are the advanced nanotechnology materials with internal or external dimensions on the order of nanometers. Their extremely small dimensions make these materials unique and promising for clean energy applications such as lithium ion batteries, supercapacitors, hydrogen storage, fuel cells, and other applications. This paper will highlight the development of new approaches to study the relationships between the structure and the physical, chemical, and electrochemical properties of functional nanostructured materials. The Energy Materials Research Programme at the Institute for Superconducting and Electronic Materials, the University of Wollongong, has been focused on …


Carbothermal Reduction Of Silica In Nitrogen And Nitrogen-Hydrogen Mixture, Xiaohan Wan, Guangqing Zhang, Oleg Ostrovski, Hal Aral Jan 2013

Carbothermal Reduction Of Silica In Nitrogen And Nitrogen-Hydrogen Mixture, Xiaohan Wan, Guangqing Zhang, Oleg Ostrovski, Hal Aral

Faculty of Engineering and Information Sciences - Papers: Part A

Carbothermal reduction of silica was investigated in a fixed bed reactor at 1300-1650 °C in nitrogen at 1-11 atm pressure and in hydrogen-nitrogen mixtures at atmospheric pressure. Samples were prepared from silica-graphite mixtures in the form of pellets. CO evolution in the reduction process was monitored using an infrared sensor; oxygen, nitrogen and carbon contents in reduced samples were determined by LECO analyses. Phases formed in the reduction process were analysed by XRD. Silica was reduced to silicon nitride and silicon carbide; their ratio was dependent on reduction time, temperature and nitrogen pressure. Reduction products also included SiO which was …


Stabilization Of Nazn(Bh4)3 Via Nanoconfinement In Sba-15 Towards Enhanced Hydrogen Release, Guanglin Xia, Li Li, Zaiping Guo, Qinfen Gu, Yanhui Guo, Xuebin Yu, Hua-Kun Liu, Zongwen Liu Jan 2013

Stabilization Of Nazn(Bh4)3 Via Nanoconfinement In Sba-15 Towards Enhanced Hydrogen Release, Guanglin Xia, Li Li, Zaiping Guo, Qinfen Gu, Yanhui Guo, Xuebin Yu, Hua-Kun Liu, Zongwen Liu

Faculty of Engineering - Papers (Archive)

In the present work, the decomposition behaviour of NaZn(BH4)3 nanoconfined in mesoporous SBA-15 has been investigated in detail and compared to bulk NaZn(BH4)3 that was ball milled with SBA-15, but not nanoconfined. The successful incorporation of nanoconfined NaZn(BH4)3 into mesopores of SBA-15 was confirmed by scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectroscopy, 11B nuclear magnetic resonance, nitrogen absorption/desorption isotherms, and Fourier transform infrared spectroscopy measurements. It is demonstrated that the dehydrogenation of the space-confined NaZn(BH4)3 is free of emission of boric by-products, and significantly improved hydrogen release kinetics is also achieved, with pure hydrogen release at temperatures …


Boron-Nitrogen-Hydrogen (Bnh) Compounds: Recent Developments In Hydrogen Storage, Applications In Hydrogenation And Catalysis, And New Syntheses, Zhenguo Huang, Tom Autrey Jan 2012

Boron-Nitrogen-Hydrogen (Bnh) Compounds: Recent Developments In Hydrogen Storage, Applications In Hydrogenation And Catalysis, And New Syntheses, Zhenguo Huang, Tom Autrey

Australian Institute for Innovative Materials - Papers

The strong efforts devoted to the exploration of BNH compounds for hydrogen storage have led to impressive advances in the field of boron chemistry. This review summarizes progress in this field from three aspects. It starts with the most recent developments in using BNH compounds for hydrogen storage, covering NH3BH3, B3H8- containing compounds, and CBN compounds. The following section then highlights interesting applications of BNH compounds in hydrogenation and catalysis. The last part is focused on breakthroughs in the syntheses and discovery of new BNH organic analogues. The role of N-Hδ+ …


Effect Of Grain Size On The Hydrogen Diffusion Process In Steel Using Cellular Automaton Approach, Druce P. Dunne, E V. Pereloma, Nima Yazdipour Jan 2012

Effect Of Grain Size On The Hydrogen Diffusion Process In Steel Using Cellular Automaton Approach, Druce P. Dunne, E V. Pereloma, Nima Yazdipour

Faculty of Engineering - Papers (Archive)

The role of microstructure in susceptibility to hydrogen uptake and property degradation is being evaluated using a number of high strength pipeline steels. To do so, a cellular automaton (CA) model has been used to examine the effect of grain size, as a first step in assessing the influence of microstructure. The simulation results of hydrogen diffusion into microstructures with different grain sizes are presented.


Microstructural Evolution During Gaseous Hydrogen Charging Of Zircaloy-4 Processed By High-Pressure Torsion: A Comparative Study, Zhiyang Wang, Huijun Li, Ulf Garbe, Mark D. Callaghan, Yanbo Wang, Xiaozhou Liao Jan 2012

Microstructural Evolution During Gaseous Hydrogen Charging Of Zircaloy-4 Processed By High-Pressure Torsion: A Comparative Study, Zhiyang Wang, Huijun Li, Ulf Garbe, Mark D. Callaghan, Yanbo Wang, Xiaozhou Liao

Faculty of Engineering - Papers (Archive)

The original and high-pressure torsion (HPT) processed Zircaloy-4 materials were hydrided using gaseous hydrogen charging at different hydrogen pressures (10, 15 and 20 atm). The phase and microstructural evolutions of the samples during hydriding were characterized. It showed that when hydriding at the identical conditions, more hydrides tended to form in the HPT samples compared to that of the original ones. At a hydrogen pressure of 20 atm, the HPT sample was completely converted to ε-ZrH2 while some δ-ZrH1.66 hydrides (volume fraction ~5.73%) were present in the material without HPT preprocessing. The HPT samples exhibited high potential for the hydride …


Effect Of Manganese Content And Microstructure On The Susceptibility Of X70 Pipeline Steel To Hydrogen Cracking, D Hejazi, A J. Haq, N Yazdipour, D P. Dunne, A Calka, Frank J. Barbaro, E V. Pereloma Jan 2012

Effect Of Manganese Content And Microstructure On The Susceptibility Of X70 Pipeline Steel To Hydrogen Cracking, D Hejazi, A J. Haq, N Yazdipour, D P. Dunne, A Calka, Frank J. Barbaro, E V. Pereloma

Faculty of Engineering and Information Sciences - Papers: Part A

The influence of composition and microstructure on susceptibility to hydrogen induced cracking (HIC) was investigated in high strength pipeline steels, with Mn contents of 1.2% (standard, X70), and 0.5% (medium, MX70). The HIC resistance of the simulated coarse grained heat affected zone microstructures and normalized X70 transfer bar was also investigated. Notched and fatigue pre-cracked samples were charged with hydrogen prior to three point bend tests. The conditional fracture toughness JQ was determined. The results are discussed in relation to grain size, microstructure, composition and the type and distribution of non-metallic inclusions and precipitates.


Improved Hydrogen Storage Properties Of Mgh2 Doped With Chlorides Of Transition Metals Hf And Fe, M Ismail Ismail, Yue Zhao, Xuebin Yu, S X. Dou Jan 2012

Improved Hydrogen Storage Properties Of Mgh2 Doped With Chlorides Of Transition Metals Hf And Fe, M Ismail Ismail, Yue Zhao, Xuebin Yu, S X. Dou

Faculty of Engineering and Information Sciences - Papers: Part A

The effects of HfCl4 and FeCl3 addition on the de/rehydrogenation properties of MgH2 were investigated. Both HfCl4 and FeCl3-doped MgH2 samples started to released hydrogen at about 270 °C, a decreased of about 70 °C and about 140 °C compared to as-milled and as-received MgH2, respectively. In terms of the desorption kinetics, the HfCl4-doped MgH2 sample showed significant improvement, with 6.0 wt.% hydrogen released within 10 min at 300 °C, while the FeCl3-doped MgH2 and undoped MgH2 samples released 3.5 and 0.2 wt.% hydrogen, respectively, under the same conditions. In terms of the absorption kinetics, 5.5 wt.% hydrogen was charged …


Enhanced Hydrogen Storage Properties Of Naalh4 Co-Catalysed With Niobium Fluoride And Single-Walled Carbon Nanotubes, Jianfeng Mao, Zaiping Guo, Hua-Kun Liu Jan 2012

Enhanced Hydrogen Storage Properties Of Naalh4 Co-Catalysed With Niobium Fluoride And Single-Walled Carbon Nanotubes, Jianfeng Mao, Zaiping Guo, Hua-Kun Liu

Australian Institute for Innovative Materials - Papers

The effects of single-walled carbon nanotubes (SWCNTs) as a co-catalyst with NbF5 on the dehydrogenation and hydrogenation kinetics of NaAlH4 were investigated by X-ray diffraction, Fourier transform infrared spectroscopy, differential thermal analysis, temperature-programmed desorption, and isothermal hydrogen ab/desorption techniques. It has been revealed that there is a synergistic effect of SWCNTs and NbF5 on the de/rehydrogenation of NaAlH4, which improves the hydrogen de/absorption performance when compared to adding either SWCNTs or NbF5 alone. For example, the apparent activation energy for the first-step and the second-step dehydrogenation of the co-doped NaAlH4 sample is estimated to be 85.9 …


Hydrogen-Induced Microstructure, Texture And Mechanical Property Evolutions In A High-Pressure Torsion Processed Zirconium Alloy, Zhiyang Wang, Ulf Garbe, Huijun Li, Andrew J. Studer, Robert P. Harrison, Mark D. Callaghan, Yanbo Wang, Xiaozhou Liao Jan 2012

Hydrogen-Induced Microstructure, Texture And Mechanical Property Evolutions In A High-Pressure Torsion Processed Zirconium Alloy, Zhiyang Wang, Ulf Garbe, Huijun Li, Andrew J. Studer, Robert P. Harrison, Mark D. Callaghan, Yanbo Wang, Xiaozhou Liao

Faculty of Engineering - Papers (Archive)

The gaseous hydriding-induced evolutions of the microstructure, texture and mechanical properties of Zircaloy-4 processed by high-pressure torsion (HPT) were assessed. Much δ-ZrH1.66 precipitation at 15 atm (21%) incurred significant hardening of vacuum-annealed HPT samples, and pure ε-ZrH2 obtained at 20 atm showed a superior microhardness of 470 HV0.3 and a low fracture toughness of 0.63 MPa m1/2. The δ-hydrides presented strong (1 1 1) texture and followed the (0 0 0 1)α-Zr//{1 1 1}δ-ZrH1.66 orientation relationship with the α-Zr matrix. During hydriding, α-Zr recrystallization texture was developed from the initial deformation texture.


Investigation Of The Hydrogen Storage Mechanism Of Expanded Graphite By Measuring Electrical Resistance Changes, Ji Sun Im, Seungsoon Jang, Youngseak Lee Jan 2012

Investigation Of The Hydrogen Storage Mechanism Of Expanded Graphite By Measuring Electrical Resistance Changes, Ji Sun Im, Seungsoon Jang, Youngseak Lee

Australian Institute for Innovative Materials - Papers

The hydrogen storage mechanism of graphite was studied by measuring the electrical resistance change. Graphite was expanded and activated to allow for an easy hydrogen molecule approach and to enlarge the adsorption sites. A vanadium catalyst was simultaneously introduced on the graphite during the activation process. The hydrogen storage increased due to the effects of expansion, activation, and the catalyst. In addition, the electrical resistance of the prepared samples was measured during hydrogen molecule adsorption to investigate the hydrogen adsorption mechanism. It was found that the electrical resistance changed as a result of the easy hydrogen molecule approach, as well …


Hydrogen De-/Absorption Improvement Of Nabh4 Catalyzed By Titanium-Based Additives, Jianfeng Mao, Zaiping Guo, Ivan P. Nevirkovets, Hua-Kun Liu, S. X. Dou Jan 2012

Hydrogen De-/Absorption Improvement Of Nabh4 Catalyzed By Titanium-Based Additives, Jianfeng Mao, Zaiping Guo, Ivan P. Nevirkovets, Hua-Kun Liu, S. X. Dou

Faculty of Engineering - Papers (Archive)

NaBH4 is considered as a promising candidate material for solid-state hydrogen storage due to its high hydrogen content of 10.6 wt %. However, its practical use is hampered by its high thermodynamic stability and slow H-exchange kinetics. In the present work, the effects of Ti-based additives, including Ti, TiH2, and TiF3, on the dehydrogenation and rehydrogenation of NaBH4 (NaH+B) were investigated. It was revealed that all of the titanium-based additives were effective in improving the hydrogen desorption and absorption reactions of NaBH4, and, among them, TiF3 possessed the highest catalytic activity. The whole dehydrogenation process for the NaBH4–0.05TiF3 sample can …