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Comparative Evaluation Of The Structural And Other Features Governing Photo-Electrochemical Oxygen Evolution By Ca/Mn Oxides, Ankita Gagrani, Mohammed Alsultan, Gerhard F. Swiegers, Takuya Tsuzuki
Comparative Evaluation Of The Structural And Other Features Governing Photo-Electrochemical Oxygen Evolution By Ca/Mn Oxides, Ankita Gagrani, Mohammed Alsultan, Gerhard F. Swiegers, Takuya Tsuzuki
Australian Institute for Innovative Materials - Papers
Mn-Based oxides, particularly CaMn oxides, have recently attracted significant practical interest as a new class of catalyst due to their elemental and structural similarity to the natural oxygen evolving cluster (OEC) in photosynthetic plant cells. However, their performance as oxygen-generating anodes in photoelectrochemical cells has not been studied in detail. In this work, ultra-fine particles of amorphous MnO2, crystalline MnO2 nanorods, Ca2Mn3O8, CaMn2O4 and CaMnO3 were synthesised using a green and scalable mechanochemical method. The particles were comparatively studied as water oxidation photocatalysts in a photo-electrochemical cell at near-neutral pH. The oxides were immobilized on the anode surface using an …
Electronic Structure Engineering Of Licoo2 Toward Enhanced Oxygen Electrocatalysis, Xiaobo Zheng, Yaping Chen, Xusheng Zheng, Guoqiang Zhao, Kun Rui, Peng Li, Xun Xu, Zhenxiang Cheng, Shi Xue Dou, Wenping Sun
Electronic Structure Engineering Of Licoo2 Toward Enhanced Oxygen Electrocatalysis, Xiaobo Zheng, Yaping Chen, Xusheng Zheng, Guoqiang Zhao, Kun Rui, Peng Li, Xun Xu, Zhenxiang Cheng, Shi Xue Dou, Wenping Sun
Australian Institute for Innovative Materials - Papers
Developing low-cost and efficient electrocatalysts for the oxygen evolution reaction and oxygen reduction reaction is of critical significance to the practical application of some emerging energy storage and conversion devices (e.g., metal-air batteries, water electrolyzers, and fuel cells). Lithium cobalt oxide is a promising nonprecious metal-based electrocatalyst for oxygen electrocatalysis; its activity, however, is still far from the requirements of practical applications. Here, a new LiCoO 2 -based electrocatalyst with nanosheet morphology is developed by a combination of Mg doping and shear force-assisted exfoliation strategies toward enhanced oxygen reduction and evolution reaction kinetics. It is demonstrated that the coupling effect …
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
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 …
Exfoliation Of Amorphous Phthalocyanine Conjugated Polymers Into Ultrathin Nanosheets For Highly Efficient Oxygen Reduction, Wenping Liu, Chiming Wang, Lijie Zhang, Houhe Pan, Wenbo Liu, Jun Chen, Dongjiang Yang, Yanjuan Xiang, Kang Wang, Jianzhuang Jiang, Xiangdong Yao
Exfoliation Of Amorphous Phthalocyanine Conjugated Polymers Into Ultrathin Nanosheets For Highly Efficient Oxygen Reduction, Wenping Liu, Chiming Wang, Lijie Zhang, Houhe Pan, Wenbo Liu, Jun Chen, Dongjiang Yang, Yanjuan Xiang, Kang Wang, Jianzhuang Jiang, Xiangdong Yao
Australian Institute for Innovative Materials - Papers
It is a significant challenge to develop a high-efficiency synthetic methodology to access fully conjugated 2D conjugated polymer (CP)/covalent organic framework (COF) nanosheets (NSs) that have great application potential for electronics and energy. Herein, we report the exfoliation of a series of amorphous ethynyl-linked phthalocyanine (Pc) CPs (MPc-CPs, M = Fe, Co, Fe0.5Co0.5) into ultrathin MPc-CP NSs. Random coupling between the four regioisomers (with D4h, D2h, C2v and Cs symmetry) of the two tetra-β-substituted phthalocyanine precursors endows the resulting phthalocyanine conjugated polymers MPc-CPs with intrinsic structural defects and a disordered framework on individual layers. This in turn induces a diminished …
Active-Site-Enriched Iron-Doped Nickel/Cobalt Hydroxide Nanosheets For Enhanced Oxygen Evolution Reaction, Qian Zhou, Yaping Chen, Guoqiang Zhao, Yue Lin, Zhenwei Yu, Xun Xu, Xiaolin Wang, Hua-Kun Liu, Wenping Sun, Shi Xue Dou
Active-Site-Enriched Iron-Doped Nickel/Cobalt Hydroxide Nanosheets For Enhanced Oxygen Evolution Reaction, Qian Zhou, Yaping Chen, Guoqiang Zhao, Yue Lin, Zhenwei Yu, Xun Xu, Xiaolin Wang, Hua-Kun Liu, Wenping Sun, Shi Xue Dou
Australian Institute for Innovative Materials - Papers
Highly active, durable, and inexpensive nanostructured catalysts are crucial for achieving efficient and economical electrochemical water splitting. However, developing efficient approaches to further improve the catalytic ability of the well-defined nanostructured catalysts is still a big challenge. Herein, we report a facile and universal cation-exchange process for synthesizing Fe-doped Ni(OH)2 and Co(OH)2 nanosheets with enriched active sites toward enhanced oxygen evolution reaction (OER). In comparison with typical NiFe layered double hydroxide (LDH) nanosteets prepared by the conventional one-pot method, Fe-doped Ni(OH)2 nanosheets evolving from Ni(OH)2 via an Fe3+/Ni2+ cation-exchange process possess nanoporous surfaces with abundant defects. Accordingly, Fe-doped Ni(OH)2 nanosheets …
Investigation On The Catalytic Performance Of Reduced‐Graphene‐Oxide‐Interpolated Fes2 And Fes For Oxygen Reduction Reaction, Hengyi Fang, Taizhong Huang, Jianfeng Mao, Shuo Yao, M Dinesh, Yue Sun, Dong Liang, Lei Qi, Jiemei Yu, Zhankun Jiang
Investigation On The Catalytic Performance Of Reduced‐Graphene‐Oxide‐Interpolated Fes2 And Fes For Oxygen Reduction Reaction, Hengyi Fang, Taizhong Huang, Jianfeng Mao, Shuo Yao, M Dinesh, Yue Sun, Dong Liang, Lei Qi, Jiemei Yu, Zhankun Jiang
Australian Institute for Innovative Materials - Papers
The oxygen reduction reaction (ORR) plays a key role in many kinds of energy conversion and energy storage devices, especially in fuel cells. Developing low-cost, easily prepared, and high-efficiency catalysts is a crucial factor for the large-scale applications of fuel cells. Herein, we report the reduced graphene oxide (rGO) interpolated FeS2and FeS as low cost and high performance electrocatalyst for ORR in the alkaline electrolyte. Cyclic voltammetry tests indicate that the onset potential of the ORR for FeS2@rGO is −0.142 V, which is close to the state-of-the-art commercial Pt/C (-0.114 V) catalyst. A low Tafel slope of ∼ 98 mV/decade …
Iron And Nickel Doped Cose2 As Efficient Non Precious Metal Catalysts For Oxygen Reduction, Beibei Yu, Jiayi Jin, Huimin Wu, Shengfu Wang, Qinghua Xia, Hua-Kun Liu
Iron And Nickel Doped Cose2 As Efficient Non Precious Metal Catalysts For Oxygen Reduction, Beibei Yu, Jiayi Jin, Huimin Wu, Shengfu Wang, Qinghua Xia, Hua-Kun Liu
Australian Institute for Innovative Materials - Papers
Iron and nickel doped CoSe2 were prepared by solvothermal method, and they were proved to be ternary chalcogenides by series of physical characterization. The effects of the iron and nickel contents on the oxygen reduction reaction were investigated by electrochemical measurements, and the highest activities were obtained on Co0.7Fe0.3Se2 and Co0.7Ni0.3Se2, respectively. Both Co0.7Fe0.3Se2 and Co0.7Ni0.3Se2 presented four-electron pathway. Furthermore, Co0.7Fe0.3Se2 exhibited more positive cathodic peak potential (0.564 V) and onset potential (0.759 V) than these of Co0.7Ni0.3Se2 (0.558 V and 0.741 V). And Co0.7Fe0.3Se2 displayed even superior stability and better tolerance to methanol, ethanol and ethylene glycol crossover effects …
Short Oxygen Plasma Treatment Leading To Long-Term Hydrophilicity Of Conductive Pcl-Ppy Nanofiber Scaffolds, Sajjad Shafei, Javad Foroughi, Zhiqiang Chen, Cynthia S. Wong, Minoo Naebe
Short Oxygen Plasma Treatment Leading To Long-Term Hydrophilicity Of Conductive Pcl-Ppy Nanofiber Scaffolds, Sajjad Shafei, Javad Foroughi, Zhiqiang Chen, Cynthia S. Wong, Minoo Naebe
Australian Institute for Innovative Materials - Papers
No abstract provided.
Self-Assembled 3d Foam-Like Nico2o4 As Efficient Catalyst For Lithium Oxygen Batteries, Lili Liu, Jun Wang, Yuyang Hou, Jun Chen, Hua-Kun Liu, Jiazhao Wang, Yu-Ping Wu
Self-Assembled 3d Foam-Like Nico2o4 As Efficient Catalyst For Lithium Oxygen Batteries, Lili Liu, Jun Wang, Yuyang Hou, Jun Chen, Hua-Kun Liu, Jiazhao Wang, Yu-Ping Wu
Australian Institute for Innovative Materials - Papers
A self-assembled 3D foam-like NiCo2O4 catalyst has been synthesized via a simple and environmental friendly approach, wherein starch acts as the template to form the unique 3D architecture. Interestingly, when employed as a cathode for lithium oxygen batteries, it demonstrates superior bifunctional electrocatalytic activities toward both the oxygen reduction reaction and the oxygen evolution reaction, with a relatively high round-trip efficiency of 70% and high discharge capacity of 10 137 mAh g-1 at a current density of 200 mA g-1, which is much higher than those in previously reported results. Meanwhile, rotating disk electrode measurements in both aqueous and nonaqueous …
Size-Dependent Chemical Reactivity Of Silicon Nanocrystals With Water And Oxygen, Melanie L. Mastronardi, Kenneth K. Chen, Kristine Liao, Gilberto Casillas, Geoffrey A. Ozin
Size-Dependent Chemical Reactivity Of Silicon Nanocrystals With Water And Oxygen, Melanie L. Mastronardi, Kenneth K. Chen, Kristine Liao, Gilberto Casillas, Geoffrey A. Ozin
Australian Institute for Innovative Materials - Papers
A detailed investigation examines how the size of allylbenzene-capped silicon nanocrystals (ncSi:AB) affects their chemical reactivity with gaseous O2, H2O, and O2/H2O as probed by in situ luminescence spectroscopy. Specifically, changes in the photoluminescence (PL) of size-separated ncSi:AB are monitored through alterations of their PL absolute quantum yield (AQY) as well as the wavelength and intensity of their PL spectra over time. These experiments, conducted under both continuous and intermittent illumination, help elucidate the roles of O2, H2O, and mixtures of O2/H2O, with respect …
A Facile Approach To Synthesize Stable Cnts@Mno Electrocatalyst For High Energy Lithium Oxygen Batteries, Wenbin Luo, Shulei Chou, Jiazhao Wang, Yu-Chun Zhai, Hua-Kun Liu
A Facile Approach To Synthesize Stable Cnts@Mno Electrocatalyst For High Energy Lithium Oxygen Batteries, Wenbin Luo, Shulei Chou, Jiazhao Wang, Yu-Chun Zhai, Hua-Kun Liu
Australian Institute for Innovative Materials - Papers
A composite of manganese monoxide loaded onto carbon nanotubes (CNTs@MnO) has been synthesized by a facile approach, in which the CNTs form a continuous conductive network connecting the electrocatalyst MnO nanoparticles together to facilitate good electrochemical performance. The electrocatalyst MnO shows favourable rechargeability, and good phase and morphology stability in lithium oxygen batteries. Excellent cycling performance is also demonstrated, in which the terminal voltage is higher than 2.4 V after 100 cycles at 0.4 mA cm-2, with 1000 mAh g-1 (composite) capacity. Therefore, this hybrid material is promising for use as a cathode material for lithium oxygen …
N-Doped Crumpled Graphene Derived From Vapor Phase Deposition Of Ppy On Graphene Aerogel As An Efficient Oxygen Reduction Reaction Electrocatalyst, Meng Wang, Jiazhao Wang, Yuyang Hou, Dongqi Shi, David Wexler, Simon D. Poynton, Robert C.T. Slade, Weimin Zhang, Hua-Kun Liu, Jun Chen
N-Doped Crumpled Graphene Derived From Vapor Phase Deposition Of Ppy On Graphene Aerogel As An Efficient Oxygen Reduction Reaction Electrocatalyst, Meng Wang, Jiazhao Wang, Yuyang Hou, Dongqi Shi, David Wexler, Simon D. Poynton, Robert C.T. Slade, Weimin Zhang, Hua-Kun Liu, Jun Chen
Australian Institute for Innovative Materials - Papers
Nitrogen-doped crumpled graphene (NCG) is successfully synthesized via vapor phase deposition of polypyrrole onto graphene aerogel followed by thermal treatment. The NCG was explored as an electrocatalyst for the oxygen reduction reaction, showing comparable electrocatalytic performance with the commercial Pt/C in alkaline membrane exchange fuel cells because of the well-regulated nitrogen doping and the robust micro-3D crumpled porous nanostructure.
One Dimensional Graphitic Carbon Nitrides As Effective Metal-Free Oxygen Reduction Catalysts, Muhammad Nawaz Tahir, Nasir Mahmood, Jinghan Zhu, Asif Mahmood, Faheem K. Butt, Syed Rizwan, Imran Aslam, M Tanveer, Faryal Idrees, Imran Shakir, Chuanbao Cao, Yanglong Hou
One Dimensional Graphitic Carbon Nitrides As Effective Metal-Free Oxygen Reduction Catalysts, Muhammad Nawaz Tahir, Nasir Mahmood, Jinghan Zhu, Asif Mahmood, Faheem K. Butt, Syed Rizwan, Imran Aslam, M Tanveer, Faryal Idrees, Imran Shakir, Chuanbao Cao, Yanglong Hou
Australian Institute for Innovative Materials - Papers
To explore the effect of morphology on catalytic properties of graphitic carbon nitride (GCN), we have studied oxygen reduction reaction (ORR) performance of two different morphologies of GCN in alkaline media. Among both, tubular GCN react with dissolved oxygen in the ORR with an onset potential close to commercial Pt/C. Furthermore, the higher stability and excellent methanol tolerance of tubular GCN compared to Pt/C emphasizes its suitability for fuel cells.
Porous Agpd-Pd Composite Nanotubes As Highly Efficient Electrocatalysts For Lithium-Oxygen Batteries, Wenbin Luo, Xuanwen Gao, Shulei Chou, Jiazhao Wang, Hua-Kun Liu
Porous Agpd-Pd Composite Nanotubes As Highly Efficient Electrocatalysts For Lithium-Oxygen Batteries, Wenbin Luo, Xuanwen Gao, Shulei Chou, Jiazhao Wang, Hua-Kun Liu
Australian Institute for Innovative Materials - Papers
Porous AgPd-Pd composite nanotubes (NTs) are used as an efficient bifunctional catalyst for the oxygen reduction and evolution reactions in lithium-oxygen batteries. The porous NT structure can facilitate rapid O2 and electrolyte diffusion through the NTs and provide abundant catalytic sites, forming a continuous conductive network throughout the entire energy conversion process, with excellent cycling performance.
Gold Nanocrystals With Variable Index Facets As Highly Effective Cathode Catalysts For Lithium-Oxygen Batteries, Dawei Su, S X. Dou, Guoxiu Wang
Gold Nanocrystals With Variable Index Facets As Highly Effective Cathode Catalysts For Lithium-Oxygen Batteries, Dawei Su, S X. Dou, Guoxiu Wang
Australian Institute for Innovative Materials - Papers
Cathode catalysts are the key factor in improving the electrochemical performance of lithium-oxygen (Li-O2) batteries via their promotion of the oxygen reduction and oxygen evolution reactions (ORR and OER). Generally, the catalytic performance of nanocrystals (NCs) toward ORR and OER depends on both composition and shape. Herein, we report the synthesis of polyhedral Au NCs enclosed by a variety of index facets: cubic gold (Au) NCs enclosed by {100} facets; truncated octahedral Au NCs enclosed by {100} and {110} facets; and trisoctahedral (TOH) Au NCs enclosed by 24 high-index {441} facets, as effective cathode catalysts for Li-O2 batteries. All Au …
Conductivity And Oxygen Reduction Activity Changes In Lanthanum Strontium Manganite Upon Low-Level Chromium Substitution, George Tsekouras, Artur Braun
Conductivity And Oxygen Reduction Activity Changes In Lanthanum Strontium Manganite Upon Low-Level Chromium Substitution, George Tsekouras, Artur Braun
Australian Institute for Innovative Materials - Papers
On the timescale of solid oxide fuel cell (SOFC) system lifetime requirements, the thermodynamically predicted low-level substitution of chromium on the B-site of (La,Sr)MnO3 could be a source of cathode degradation underlying more overt and well-known chromium poisoning mechanisms. To study this phenomenon in isolation, electronic conductivity (σ) and electrochemical oxygen reduction activity of the (La0.8Sr0.2)0.98CrxMn1−xO3 model series (x = 0, 0.02, 0.05 or 0.1) were measured in air between 850 and 650 °C. Depending on the extent of chromium substitution and the measurement temperature, electrochemical …
A New Strategy For Integrating Abundant Oxygen Functional Groups Into Carbon Felt Electrode For Vanadium Redox Flow Batteries, Ki Jae Kim, Seung-Wook Lee, Taeeun Yim, Jae-Geun Kim, Jang Wook Choi, Jung Ho Kim, Min-Sik Park, Young-Jun Kim
A New Strategy For Integrating Abundant Oxygen Functional Groups Into Carbon Felt Electrode For Vanadium Redox Flow Batteries, Ki Jae Kim, Seung-Wook Lee, Taeeun Yim, Jae-Geun Kim, Jang Wook Choi, Jung Ho Kim, Min-Sik Park, Young-Jun Kim
Australian Institute for Innovative Materials - Papers
The effects of surface treatment combining corona discharge and hydrogen peroxide (H2O2) on the electrochemical performance of carbon felt electrodes for vanadium redox flow batteries (VRFBs) have been thoroughly investigated. A high concentration of oxygen functional groups has been successfully introduced onto the surface of the carbon felt electrodes by a specially designed surface treatment, which is mainly responsible for improving the energy efficiency of VRFBs. In addition, the wettability of the carbon felt electrodes also can be significantly improved. The energy efficiency of the VRFB cell employing the surface modified carbon felt electrodes is improved by 7% at high …
Effects Of Oxygen Adsorption On The Surface State Of Epitaxial Silicene On Ag(111), Xun Xu, Jincheng Zhuang, Yi Du, Haifeng Feng, N Zhang, Chen Liu, Tao Lei, Jiaou Wang, M Spencer, Tetsuya Morishita, Xiaolin Wang, S X. Dou
Effects Of Oxygen Adsorption On The Surface State Of Epitaxial Silicene On Ag(111), Xun Xu, Jincheng Zhuang, Yi Du, Haifeng Feng, N Zhang, Chen Liu, Tao Lei, Jiaou Wang, M Spencer, Tetsuya Morishita, Xiaolin Wang, S X. Dou
Australian Institute for Innovative Materials - Papers
Epitaxial silicene, which is one single layer of silicon atoms packed in a honeycomb structure, demonstrates a strong interaction with the substrate that dramatically affects its electronic structure. The role of electronic coupling in the chemical reactivity between the silicene and the substrate is still unclear so far, which is of great importance for functionalization of silicene layers. Here, we report the reconstructions and hybridized electronic structures of epitaxial 4 3 4 silicene on Ag(111), which are revealed by scanning tunneling microscopy and angle-resolved photoemission spectroscopy. The hybridization between Si and Ag results in a metallic surface state, which can …
Co3o4 Nanorods Decorated Reduced Graphene Oxide Composite For Oxygen Reduction Reaction In Alkaline Electrolyte, Mingyan Wang, Junrao Huang, Meng Wang, Dongen Zhang, Weimin Zhang, Weihua Li, Jun Chen
Co3o4 Nanorods Decorated Reduced Graphene Oxide Composite For Oxygen Reduction Reaction In Alkaline Electrolyte, Mingyan Wang, Junrao Huang, Meng Wang, Dongen Zhang, Weimin Zhang, Weihua Li, Jun Chen
Australian Institute for Innovative Materials - Papers
Highly uniform Co3O4 nanorods decorated on reduced graphene oxide (rGO) were prepared by a one-pot hydrothermal procedure. During the hydrothermal process, Co2+ ions were crystallized to Co3O4 nanorods and simultaneously GO was reduced to rGO to form the Co3O4/rGO hybrid. The Co3O4/rGO hybrid was characterized by scanning electron micrographs, X-ray diffraction, X-ray photoelectron spectroscopy, and Raman spectroscopy. The obtained Co3O4/rGO hybrid exhibits excellent electrocatalytic performance for oxygen reduction reaction.
Pdni Hollow Nanoparticles For Improved Electrocatalytic Oxygen Reduction In Alkaline Environments, Meng Wang, Weimin Zhang, Jiazhao Wang, David Wexler, Simon D. Poynton, Robert C.T Slade, Hua-Kun Liu, Bjorn Winther-Jensen, Robert Kerr, Dongqi Shi, Jun Chen
Pdni Hollow Nanoparticles For Improved Electrocatalytic Oxygen Reduction In Alkaline Environments, Meng Wang, Weimin Zhang, Jiazhao Wang, David Wexler, Simon D. Poynton, Robert C.T Slade, Hua-Kun Liu, Bjorn Winther-Jensen, Robert Kerr, Dongqi Shi, Jun Chen
Australian Institute for Innovative Materials - Papers
Palladium-Nickel (Pd-Ni) hollow nanoparticles were synthesized via a modified galvanic replacement method using Ni nanoparticles as sacrificial templates in an aqueous medium. X-ray diffraction and transmission electron microscopy show that the as-synthesized nanoparticles are alloyed nanostructures and have hollow interiors with an average particle size of 30 nm and shell thickness of 5 nm. Compared with the commercially available Pt/C or Pd/C catalysts, the synthesized PdNi/C has superior electrocatalytic performance towards the oxygen reduction reaction, which makes it a promising electrocatalyst for alkaline anion exchange membrane fuel cells and alkali-based air-batteries. The electrocatalyst is finally examined in an H2/O2 alkaline …
Atomic And Electronic Structures Of Single-Layer Fese On Srtio3(001): The Role Of Oxygen Deficiency, Junhyeok Bang, Zhi Li, Y Y. Sun, Amit Samanta, Y Y. Zhang, Wenhao Zhang, Lili Wang, Xi Chen, Xu-Cun Ma, Qi-Kun Xue, S B. Zhang
Atomic And Electronic Structures Of Single-Layer Fese On Srtio3(001): The Role Of Oxygen Deficiency, Junhyeok Bang, Zhi Li, Y Y. Sun, Amit Samanta, Y Y. Zhang, Wenhao Zhang, Lili Wang, Xi Chen, Xu-Cun Ma, Qi-Kun Xue, S B. Zhang
Australian Institute for Innovative Materials - Papers
Using first-principles calculation, we propose an interface structure for single triple-layer FeSe on the SrTiO3(001) surface, a high-Tc superconductor found recently. The key component of this structure is the oxygen deficiency on the top layer of the SrTiO3 substrate, as a result of Se etching used in preparing the high-Tc samples. The O vacancies strongly bind the FeSe triple layer to the substrate giving rise to a (2 x 1) reconstruction, as observed by scanning tunneling microscopy. The enhanced binding correlates to the significant increase of Tc observed in experiment. The O vacancies also serve as the source of electron …
In-Field Jc Improvement By Oxygen-Free Pyrene Gas Diffusion Into Highly Dense Mgb2 Superconductor, Minoru Maeda, Jung Ho Kim, Y Zhao, Yoon-Uk Heo, K Takase, Y Kubota, C Moriyoshi, F Yoshida, Y Kuroiwa, S X. Dou
In-Field Jc Improvement By Oxygen-Free Pyrene Gas Diffusion Into Highly Dense Mgb2 Superconductor, Minoru Maeda, Jung Ho Kim, Y Zhao, Yoon-Uk Heo, K Takase, Y Kubota, C Moriyoshi, F Yoshida, Y Kuroiwa, S X. Dou
Australian Institute for Innovative Materials - Papers
Oxygen-free pyrene gas as a carbon (C) dopant was delinked and incorporated into highly dense MgB2 structure via a gas phase diffusion method. The technique offers the advantages that molecular C is homogeneously distributed into MgB2 and substituted at the boron sites without any severe deterioration of grain connectivity. The C substitution causes a significant shrinkage of the a-lattice parameter and an increase in the lattice strain, resulting in high disorder. The introduction of structural disorder as a result of C doping leads to a considerable enhancement of the in-field critical current density (Jc) and upper critical …
Position Preference And Diffusion Path Of An Oxygen Ion In Apatite-Type Lanthanum Silicate La9.33si6o26: A Density Functional Study, Ting Liao, Taizo Sasaki, Shigeru Suehara, Ziqi Sun
Position Preference And Diffusion Path Of An Oxygen Ion In Apatite-Type Lanthanum Silicate La9.33si6o26: A Density Functional Study, Ting Liao, Taizo Sasaki, Shigeru Suehara, Ziqi Sun
Australian Institute for Innovative Materials - Papers
Using density functional theory, we investigated the position preference and diffusion mechanisms of interstitial oxygen ions in lanthanum silicate La9.33Si6O26, which is an apatite-structured oxide and a promising candidate electrolyte material for solid oxide fuel cells. The reported lanthanum vacancies were explicitly taken into account by theoretically determining their arrangement with a supercell model. The most stable structures and the formation energies of oxygen interstitials were determined for each charged state. It was found that the double-negatively charged state is stable over a wide range of the Fermi level, and that the excess oxygen …