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Full-Text Articles in Physical Sciences and Mathematics

High Performance Pure Sulfur Honeycomb-Like Architectures Synthesized By A Cooperative Self-Assembly Strategy For Lithium Sulfur Batteries, Xin Liang, Mohammad Kaiser, Konstantin Konstantinov, Richard Tandiono, Zhaoxiang Prof Zhaoxiang Wang, Hua-Kun Liu, S X. Dou, Jiazhao Wang Oct 2014

High Performance Pure Sulfur Honeycomb-Like Architectures Synthesized By A Cooperative Self-Assembly Strategy For Lithium Sulfur Batteries, Xin Liang, Mohammad Kaiser, Konstantin Konstantinov, Richard Tandiono, Zhaoxiang Prof Zhaoxiang Wang, Hua-Kun Liu, S X. Dou, Jiazhao Wang

Shi Xue Dou

Honeycomb-like pure sulfur architectures were synthesized by a cooperative self-assembly strategy, in which a soft template is used to form the porous structure. Their electrochemical performance is significantly improved comparing with the commercial sulfur powder and the as-prepared sulfur without honeycomb morphology. There has been no report on using a soft template to prepare honeycomb-like sulfur particles.


Thermoelectric Performance Of N-Type (Pbte)0.75(Pbs)0.15(Pbse)0.1 Composites, Sima Aminorroaya Yamini, Heng Wang, Dianta Ginting, David R. G Mitchell, S X. Dou, G. Jeffrey Snyder Oct 2014

Thermoelectric Performance Of N-Type (Pbte)0.75(Pbs)0.15(Pbse)0.1 Composites, Sima Aminorroaya Yamini, Heng Wang, Dianta Ginting, David R. G Mitchell, S X. Dou, G. Jeffrey Snyder

Shi Xue Dou

Lead chalcogenides (PbQ, Q = Te, Se, S) have proved to possess high thermoelectric efficiency for both n-type and p-type compounds. Recent success in tuning of electronic band structure, including manipulating the band gap, multiple bands, or introducing resonant states, has led to a significant improvement in the thermoelectric performance of p-type lead chalcogenides compared to the n-type ones. Here, the n-type quaternary composites of (PbTe)0.75(PbS)0.15(PbSe)0.1 are studied to evaluate the effects of nanostructuring on lattice thermal conductivity, carrier mobility, and effective mass variation. The results are compared with the similar ternary systems of (PbTe)1-x(PbSe)x, (PbSe) 1-x(PbS)x, and (PbS)1-x(PbTe)x. The …


Thermoelectric Performance Of Tellurium-Reduced Quaternary P-Type Lead-Chalcogenide Composites, Sima Aminorroaya Yamini, Heng Wang, Zachary M. Gibbs, Yanzhong Pei, David R. G Mitchell, S X. Dou, G. Jeffrey Snyder Oct 2014

Thermoelectric Performance Of Tellurium-Reduced Quaternary P-Type Lead-Chalcogenide Composites, Sima Aminorroaya Yamini, Heng Wang, Zachary M. Gibbs, Yanzhong Pei, David R. G Mitchell, S X. Dou, G. Jeffrey Snyder

Shi Xue Dou

A long-standing technological challenge to the widespread application of thermoelectric generators is obtaining high-performance thermoelectric materials from abundant elements. Intensive study on PbTe alloys has resulted in a high figure of merit for the single-phase ternary PbTe-PbSe system through band structure engineering, and the low thermal conductivity achieved due to nanostructuring leads to high thermoelectric performance for ternary PbTe-PbS compounds. Recently, the single-phase p-type quaternary PbTe-PbSe-PbS alloys have been shown to provide thermoelectric performance superior to the binary and ternary lead chalcogenides. This occurs via tuning of the band structure and from an extraordinary low thermal conductivity resulting from high-contrast …


High-Performance Sodium-Ion Batteries And Sodium-Ion Pseudocapacitors Based On Mos2/Graphene Composites, Yunxiao Wang, Shulei Chou, David Wexler, Hua-Kun Liu, S X. Dou Oct 2014

High-Performance Sodium-Ion Batteries And Sodium-Ion Pseudocapacitors Based On Mos2/Graphene Composites, Yunxiao Wang, Shulei Chou, David Wexler, Hua-Kun Liu, S X. Dou

Shi Xue Dou

Sodium-ion energy storage, including sodium-ion batteries (NIBs) and electrochemical capacitive storage (NICs), is considered as a promising alternative to lithium-ion energy storage. It is an intriguing prospect, especially for large-scale applications, owing to its low cost and abundance. MoS2 sodiation/desodiation with Na ions is based on the conversion reaction, which is not only able to deliver higher capacity than the intercalation reaction, but can also be applied in capacitive storage owing to its typically sloping charge/discharge curves. Here, NIBs and NICs based on a graphene composite (MoS2/G) were constructed. The enlarged d-spacing, a contribution of the graphene matrix, and the …


Ultra-High Performance, High-Temperature Superconducting Wires Via Cost-Effective, Scalable, Co-Evaporation Process, Ho-Sup Kim, Sang-Soo Oh, Hong-Soo Ha, Dojun Youm, Seung-Hyun Moon, Jung Ho Kim, S X. Dou, Yoon-Uk Heo, Sung-Hun Wee, Amit Goyal Oct 2014

Ultra-High Performance, High-Temperature Superconducting Wires Via Cost-Effective, Scalable, Co-Evaporation Process, Ho-Sup Kim, Sang-Soo Oh, Hong-Soo Ha, Dojun Youm, Seung-Hyun Moon, Jung Ho Kim, S X. Dou, Yoon-Uk Heo, Sung-Hun Wee, Amit Goyal

Shi Xue Dou

Long-length, high-temperature superconducting (HTS) wires capable of carrying high critical current, Ic, are required for a wide range of applications. Here, we report extremely high performance HTS wires based on 5 μm thick SmBa2Cu3O7 − δ (SmBCO) single layer films on textured metallic templates. SmBCO layer wires over 20 meters long were deposited by a cost-effective, scalable co-evaporation process using a batch-type drum in a dual chamber. All deposition parameters influencing the composition, phase, and texture of the films were optimized via a unique combinatorial method that is broadly applicable for co-evaporation of other promising complex materials containing several cations. …


Reliable And Efficient Multithreading, Tongping Liu Aug 2014

Reliable And Efficient Multithreading, Tongping Liu

Doctoral Dissertations

The advent of multicore architecture has increased the demand for multithreaded programs. It is notoriously far more challenging to write parallel programs correctly and efficiently than sequential ones because of the wide range of concurrency errors and performance problems. In this thesis, I developed a series of runtime systems and tools to combat concurrency errors and performance problems of multithreaded programs. The first system, Dthreads, automatically ensures determinism for unmodified C/C++ applications using the pthreads library without requiring programmer intervention and hardware support. Dthreads greatly simplifies the understanding and debugging of multithreaded programs. Dthreads often matches or even exceeds the …


Aqueous Dispersions Of Reduced Graphene Oxide And Multi Wall Carbon Nanotubes For Enhanced Glucose Oxidase Bioelectrode Performance, Willo Grosse, Joffrey Champavert, Sanjeev Gambhir, Gordon G. Wallace, Simon E. Moulton Mar 2014

Aqueous Dispersions Of Reduced Graphene Oxide And Multi Wall Carbon Nanotubes For Enhanced Glucose Oxidase Bioelectrode Performance, Willo Grosse, Joffrey Champavert, Sanjeev Gambhir, Gordon G. Wallace, Simon E. Moulton

Gordon Wallace

Aqueous dispersions of reduced graphene oxide (rGO) and multi walled carbon nanotubes (MWCNT) were fabricated through a modified chemical reduction method. The significant advantage of the method developed here is the omission of any stabilising compound or organic solvent to obtain stable rGO-MWCNT dispersions. Significantly biological entities, in this case the enzyme glucose oxidase (GOx), can be successfully incorporated into the dispersion. These dispersions were characterised using XPS, SEM, zeta potential and particle size measurements which showed that the dispersion stability is not sacrificed with the addition of GOx, and significantly, the electrical properties of the rGO and MWCNTs are …


Evaluation Of Encapsulating Coatings On The Performance Of Polypyrrole Actuators, Sina Naficy, Nicholas Stoboi, Philip G. Whitten, Geoffrey M. Spinks, Gordon G. Wallace Mar 2014

Evaluation Of Encapsulating Coatings On The Performance Of Polypyrrole Actuators, Sina Naficy, Nicholas Stoboi, Philip G. Whitten, Geoffrey M. Spinks, Gordon G. Wallace

Gordon Wallace

Conjugated polymer actuators are electroactive materials capable of generating force and movement in response to an applied external voltage. Many potential biomedical and industrial applications require these actuators to operate in a liquid environment. However, immersion of uncoated conducting polymer actuators in non-electrolyte liquids greatly reduces their operating lifetime. Here, we demonstrate the use of spray coating as an effective and simple method to encapsulate polypyrrole (PPy) tri-layer bending actuators. Poly(styrene-b-isobutylene-b-styrene) (SIBS) was used as an encapsulating, compliant spray coating on PPy actuators. A significant enhancement in actuator lifetime in both air and water was observed by encapsulating the actuators. …


Cation Exchange At Semiconducting Oxide Surfaces: Origin Of Light-Induced Performance Increases In Porphyrin Dye-Sensitized Solar Cells, Matthew J. Griffith, Kenji Sunahara, Akihiro Furube, Attila J. Mozer, David L. Officer, Pawel Wagner, Gordon G. Wallace, Shogo Mori Mar 2014

Cation Exchange At Semiconducting Oxide Surfaces: Origin Of Light-Induced Performance Increases In Porphyrin Dye-Sensitized Solar Cells, Matthew J. Griffith, Kenji Sunahara, Akihiro Furube, Attila J. Mozer, David L. Officer, Pawel Wagner, Gordon G. Wallace, Shogo Mori

Gordon Wallace

The origin of simultaneous improvements in the short-circuit current density (Jsc) and open-circuit voltage (Voc) of porphyrin dye-sensitized TiO2 solar cells following white light illumination was studied by systematic variation of several different device parameters. Reduction of the dye surface loading resulted in greater relative performance enhancements, suggesting open space at the TiO2 surface expedites the process. Variation of the electrolyte composition and subsequent analysis of the conduction band potential shifts suggested that a light-induced replacement of surface-adsorbed lithium (Li+) ions with dimethylpropylimidazolium (DMPIm+) ions was responsible for an increased electron lifetime by decreasing the recombination with the redox mediator. …


A Facile Route To Synthesize Transition Metal Oxide/Reduced Graphene Oxide Composites And Their Lithium Storage Performance, Chongjun Zhao, Shulei Chou, Yunxiao Wang, Cuifeng Zhou, Hua-Kun Liu, S X. Dou Mar 2014

A Facile Route To Synthesize Transition Metal Oxide/Reduced Graphene Oxide Composites And Their Lithium Storage Performance, Chongjun Zhao, Shulei Chou, Yunxiao Wang, Cuifeng Zhou, Hua-Kun Liu, S X. Dou

Shi Xue Dou

Transition metal oxide (Mn3O4, Fe2O3, Co3O4, and ZnO) and reduced graphene oxide (RGO) composites were successfully synthesized via a hydrothermal method using the direct reaction between the corresponding metal powder and graphene oxide (GO). In this process, the GO can be reduced by transition metal powder in water, and the nanosized metal oxide can be obtained, and homogeneously mixed with and wrapped by RGO to form a metal oxide/RGO composite at the same time. X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, and scanning and transmission electron microscopy were used to characterize the as-prepared materials. The different experimental parameters, including reactants, …


Synergetic Combination Of Limd With Chpd For The Production Of Economical And High Performance Mgb2 Wires, Minoru Maeda, Md Shahriar Ai Hossain, Ashkan Motaman, Jung Ho Kim, Anna Kario, Matt Rindfleisch, Mike Tomsic, S X. Dou Mar 2014

Synergetic Combination Of Limd With Chpd For The Production Of Economical And High Performance Mgb2 Wires, Minoru Maeda, Md Shahriar Ai Hossain, Ashkan Motaman, Jung Ho Kim, Anna Kario, Matt Rindfleisch, Mike Tomsic, S X. Dou

Shi Xue Dou

We propose an economical fabrication concept, the localized internal magnesium diffusion (IMD) method. Instead of using a single magnesium (Mg) rod in the center of a metal sheath tube, we use large-sized Mg particles (20-50 mesh) mixed well with cheap 97% crystalline boron powder to fill the metal sheath tube. After a repeated drawing process, the coarse Mg is elongated along the core wire axis of the metal sheath tube. Textured MgB2 grains are then formed during the sintering process. In the localized IMD process, however, there is still a need to improve the overall density. In order to increase …


Mesoporous Hexagonal Co3o4 For High Performance Lithium Ion Batteries, Dawei Su, Xiuqiang Xie, Paul Munroe, S X. Dou, Guoxiu Wang Jan 2014

Mesoporous Hexagonal Co3o4 For High Performance Lithium Ion Batteries, Dawei Su, Xiuqiang Xie, Paul Munroe, S X. Dou, Guoxiu Wang

Australian Institute for Innovative Materials - Papers

Mesoporous Co3O4 nanoplates were successfully prepared by the conversion of hexagonal beta-Co(OH)(2) nanoplates. TEM, HRTEM and N-2 sorption analysis confirmed the facet crystal structure and inner mesoporous architecture. When applied as anode materials for lithium storage in lithium ion batteries, mesoporous Co3O4 nanocrystals delivered a high specific capacity. At 10 degrees C current rate, as-prepared mesoporous Co3O4 nanoplates delivered a specific capacity of 1203 mAh/g at first cycle and after 200 cycles it can still maintain a satisfied value (330 mAh/g). Fromex-situ TEM, SAED and FESEM observation, it was found that mesoporous Co3O4 nanoplates were reduced to Li2O and Co …


Sulfur-Graphene Nanostructured Cathodes Via Ball-Milling For High-Performance Lithium-Sulfur Batteries, Jiantie Xu, Jianglan Shui, Jianli Wang, Min Wang, Hua-Kun Liu, S X. Dou, In-Yup Jeon, Jeong-Min Seo, Jong-Beom Baek, Liming Dai Jan 2014

Sulfur-Graphene Nanostructured Cathodes Via Ball-Milling For High-Performance Lithium-Sulfur Batteries, Jiantie Xu, Jianglan Shui, Jianli Wang, Min Wang, Hua-Kun Liu, S X. Dou, In-Yup Jeon, Jeong-Min Seo, Jong-Beom Baek, Liming Dai

Australian Institute for Innovative Materials - Papers

Although much progress has been made to develop high-performance lithium-sulfur batteries (LSBs), the reported physical or chemical routes to sulfur cathode materials are often multistep/complex and even involve environmentally hazardous reagents, and hence are infeasible for mass production. Here, we report a simple ball-milling technique to combine both the physical and chemical routes into a one-step process for low-cost, scalable, and eco-friendly production of graphene nanoplatelets (GnPs) edge-functionalized with sulfur (S-GnPs) as highly efficient LSB cathode materials of practical significance. LSBs based on the S-GnP cathode materials, produced by ball-milling 70 wt % sulfur and 30 wt % graphite, delivered …


The Synergistic Effect Between Wo3 And G-C3n4 Towards Efficient Visible-Light-Driven Photocatalytic Performance, Imran Aslam, Chuanbao Cao, M Tanveer, Waheed S. Khan, Muhammad Nawaz Tahir, Muhammad Abid, Faryal Idrees, Faheem K. Butt, Zulfiqar Ali, Nasir Mahmood Jan 2014

The Synergistic Effect Between Wo3 And G-C3n4 Towards Efficient Visible-Light-Driven Photocatalytic Performance, Imran Aslam, Chuanbao Cao, M Tanveer, Waheed S. Khan, Muhammad Nawaz Tahir, Muhammad Abid, Faryal Idrees, Faheem K. Butt, Zulfiqar Ali, Nasir Mahmood

Australian Institute for Innovative Materials - Papers

We have developed a facile, scaled up, efficient and morphology-based novel WO3-g-C3N4 photocatalyst with different mass ratios of WO3 and g-C3N4. It was used for the photodegradation of rhodamine B (RhB) under visible light irradiation and it showed excellent enhanced photocatalytic efficiency as compared to pure g-C3N4 and WO3. The apparent performance of the composite/hybrid was 3.65 times greater than pure WO3 and 3.72 times greater than pure g-C3N4 respectively, and it was also found to be much higher than the previously reported ones. Furthermore, the optical properties of composite samples were evaluated. The bandgap of composite samples lies in …


Ultra-High Performance, High-Temperature Superconducting Wires Via Cost-Effective, Scalable, Co-Evaporation Process, Ho-Sup Kim, Sang-Soo Oh, Hong-Soo Ha, Dojun Youm, Seung-Hyun Moon, Jung Ho Kim, S X. Dou, Yoon-Uk Heo, Sung-Hun Wee, Amit Goyal Jan 2014

Ultra-High Performance, High-Temperature Superconducting Wires Via Cost-Effective, Scalable, Co-Evaporation Process, Ho-Sup Kim, Sang-Soo Oh, Hong-Soo Ha, Dojun Youm, Seung-Hyun Moon, Jung Ho Kim, S X. Dou, Yoon-Uk Heo, Sung-Hun Wee, Amit Goyal

Australian Institute for Innovative Materials - Papers

Long-length, high-temperature superconducting (HTS) wires capable of carrying high critical current, Ic, are required for a wide range of applications. Here, we report extremely high performance HTS wires based on 5 μm thick SmBa2Cu3O7 − δ (SmBCO) single layer films on textured metallic templates. SmBCO layer wires over 20 meters long were deposited by a cost-effective, scalable co-evaporation process using a batch-type drum in a dual chamber. All deposition parameters influencing the composition, phase, and texture of the films were optimized via a unique combinatorial method that is broadly applicable for co-evaporation of other promising complex materials containing several cations. …


High-Performance Sodium-Ion Batteries And Sodium-Ion Pseudocapacitors Based On Mos2/Graphene Composites, Yunxiao Wang, Shulei Chou, David Wexler, Hua-Kun Liu, S X. Dou Jan 2014

High-Performance Sodium-Ion Batteries And Sodium-Ion Pseudocapacitors Based On Mos2/Graphene Composites, Yunxiao Wang, Shulei Chou, David Wexler, Hua-Kun Liu, S X. Dou

Australian Institute for Innovative Materials - Papers

Sodium-ion energy storage, including sodium-ion batteries (NIBs) and electrochemical capacitive storage (NICs), is considered as a promising alternative to lithium-ion energy storage. It is an intriguing prospect, especially for large-scale applications, owing to its low cost and abundance. MoS2 sodiation/desodiation with Na ions is based on the conversion reaction, which is not only able to deliver higher capacity than the intercalation reaction, but can also be applied in capacitive storage owing to its typically sloping charge/discharge curves. Here, NIBs and NICs based on a graphene composite (MoS2/G) were constructed. The enlarged d-spacing, a contribution of the graphene matrix, and the …


Enhanced Sodium-Ion Battery Performance By Structural Phase Transition From Two-Dimensional Hexagonal-Sns2 To Orthorhombic-Sns, Tengfei Zhou, Wei Kong Pang, Chaofeng Zhang, Jianping Yang, Zhixin Chen, Hua-Kun Liu, Zaiping Guo Jan 2014

Enhanced Sodium-Ion Battery Performance By Structural Phase Transition From Two-Dimensional Hexagonal-Sns2 To Orthorhombic-Sns, Tengfei Zhou, Wei Kong Pang, Chaofeng Zhang, Jianping Yang, Zhixin Chen, Hua-Kun Liu, Zaiping Guo

Australian Institute for Innovative Materials - Papers

Structural phase transitions can be used to alter the properties of a material without adding any additional elements and are therefore of significant technological value. It was found that the hexagonal-SnS2 phase can be transformed into the orthorhombic-SnS phase after an annealing step in an argon atmosphere, and the thus transformed SnS shows enhanced sodium-ion storage performance over that of the SnS2, which is attributed to its structural advantages. Here, we provide the first report on a SnS@graphene architecture for application as a sodium-ion battery anode, which is built from two-dimensional SnS and graphene nanosheets as complementary building blocks. The …


Thermoelectric Performance Of N-Type (Pbte)0.75(Pbs)0.15(Pbse)0.1 Composites, Sima Aminorroaya Yamini, Heng Wang, Dianta Ginting, David R. G Mitchell, S X. Dou, G. Jeffrey Snyder Jan 2014

Thermoelectric Performance Of N-Type (Pbte)0.75(Pbs)0.15(Pbse)0.1 Composites, Sima Aminorroaya Yamini, Heng Wang, Dianta Ginting, David R. G Mitchell, S X. Dou, G. Jeffrey Snyder

Australian Institute for Innovative Materials - Papers

Lead chalcogenides (PbQ, Q = Te, Se, S) have proved to possess high thermoelectric efficiency for both n-type and p-type compounds. Recent success in tuning of electronic band structure, including manipulating the band gap, multiple bands, or introducing resonant states, has led to a significant improvement in the thermoelectric performance of p-type lead chalcogenides compared to the n-type ones. Here, the n-type quaternary composites of (PbTe)0.75(PbS)0.15(PbSe)0.1 are studied to evaluate the effects of nanostructuring on lattice thermal conductivity, carrier mobility, and effective mass variation. The results are compared with the similar ternary systems of (PbTe)1-x(PbSe)x, (PbSe) 1-x(PbS)x, and (PbS)1-x(PbTe)x. The …


High Performance Pure Sulfur Honeycomb-Like Architectures Synthesized By A Cooperative Self-Assembly Strategy For Lithium Sulfur Batteries, Xin Liang, Mohammad Kaiser, Konstantin Konstantinov, Richard Tandiono, Zhaoxiang Prof Zhaoxiang Wang, Hua-Kun Liu, S X. Dou, Jiazhao Wang Jan 2014

High Performance Pure Sulfur Honeycomb-Like Architectures Synthesized By A Cooperative Self-Assembly Strategy For Lithium Sulfur Batteries, Xin Liang, Mohammad Kaiser, Konstantin Konstantinov, Richard Tandiono, Zhaoxiang Prof Zhaoxiang Wang, Hua-Kun Liu, S X. Dou, Jiazhao Wang

Australian Institute for Innovative Materials - Papers

Honeycomb-like pure sulfur architectures were synthesized by a cooperative self-assembly strategy, in which a soft template is used to form the porous structure. Their electrochemical performance is significantly improved comparing with the commercial sulfur powder and the as-prepared sulfur without honeycomb morphology. There has been no report on using a soft template to prepare honeycomb-like sulfur particles.


Performance Enhancement Of Single-Walled Nanotube-Microwave Exfoliated Graphene Oxide Composite Electrodes Using A Stacked Electrode Configuration, Dennis Antiohos, Mark S. Romano, Joselito M. Razal, Stephen Beirne, Phil Aitchison, Andrew I. Minett, Gordon G. Wallace, Jun Chen Jan 2014

Performance Enhancement Of Single-Walled Nanotube-Microwave Exfoliated Graphene Oxide Composite Electrodes Using A Stacked Electrode Configuration, Dennis Antiohos, Mark S. Romano, Joselito M. Razal, Stephen Beirne, Phil Aitchison, Andrew I. Minett, Gordon G. Wallace, Jun Chen

Australian Institute for Innovative Materials - Papers

We report the development of a stacked electrode supercapacitor cell using stainless steel meshes as the current collectors and optimised single walled nanotubes (SWNT)-microwave exfoliated graphene oxide (mw rGO) composites as the electrode material. The introduction of mw rGO into a SWNT matrix creates an intertwined porous structure that enhances the electroactive surface area and capacitive performance due to the 3-D hierarchical structure that is formed. The composite structure was optimised by varying the weight ratio of the SWNTs and mw rGO. The best performing ratio was the 90% SWNT-10% mw rGO electrode which achieved a specific capacitance of 306 …


Thermoelectric Performance Of Tellurium-Reduced Quaternary P-Type Lead-Chalcogenide Composites, Sima Aminorroaya Yamini, Heng Wang, Zachary M. Gibbs, Yanzhong Pei, David R. G Mitchell, S X. Dou, G. Jeffrey Snyder Jan 2014

Thermoelectric Performance Of Tellurium-Reduced Quaternary P-Type Lead-Chalcogenide Composites, Sima Aminorroaya Yamini, Heng Wang, Zachary M. Gibbs, Yanzhong Pei, David R. G Mitchell, S X. Dou, G. Jeffrey Snyder

Australian Institute for Innovative Materials - Papers

A long-standing technological challenge to the widespread application of thermoelectric generators is obtaining high-performance thermoelectric materials from abundant elements. Intensive study on PbTe alloys has resulted in a high figure of merit for the single-phase ternary PbTe-PbSe system through band structure engineering, and the low thermal conductivity achieved due to nanostructuring leads to high thermoelectric performance for ternary PbTe-PbS compounds. Recently, the single-phase p-type quaternary PbTe-PbSe-PbS alloys have been shown to provide thermoelectric performance superior to the binary and ternary lead chalcogenides. This occurs via tuning of the band structure and from an extraordinary low thermal conductivity resulting from high-contrast …


Mechanically Strong High Performance Layered Polypyrrole Nano Fibre/Graphene Film For Flexible Solid State Supercapacitor, Sha Li, Chen Zhao, Kewei Shu, Caiyun Wang, Zaiping Guo, Gordon G. Wallace, Hua-Kun Liu Jan 2014

Mechanically Strong High Performance Layered Polypyrrole Nano Fibre/Graphene Film For Flexible Solid State Supercapacitor, Sha Li, Chen Zhao, Kewei Shu, Caiyun Wang, Zaiping Guo, Gordon G. Wallace, Hua-Kun Liu

Australian Institute for Innovative Materials - Papers

Paper like flexible electrode becomes one of the most important research objects recently in request of the fast expanding market of portable electronics. Flexible solid state supercapacitors are shortlisted as one of the most promising energy devices to power electronics with medium to high power density requirements. In this work, we developed a simple but effective way to produce a mechanically strong and electrochemically active RGO/polypyrrole (PPy) fibre paper. A well-bedded microstructure was created with interlaced polypyrrole fibres evenly distributed between the graphene layers. Such microstructure can create enormous amount of pores and therefore provides larger interfaces for charge carrier …


Enhanced Performance Of Dye-Sensitized Solar Cells Using Carbazole-Substituted Di-Chromophoric Porphyrin Dyes, Long Zhao, Pawel Wagner, Anastasia Elliott, Matthew Griffith, Tracey M. Clarke, Keith C. Gordon, Shogo Mori, Attila Mozer Jan 2014

Enhanced Performance Of Dye-Sensitized Solar Cells Using Carbazole-Substituted Di-Chromophoric Porphyrin Dyes, Long Zhao, Pawel Wagner, Anastasia Elliott, Matthew Griffith, Tracey M. Clarke, Keith C. Gordon, Shogo Mori, Attila Mozer

Australian Institute for Innovative Materials - Papers

The purpose of this work is to investigate the origin of improved photovoltaic performance of a series of di-chromophoric carbazole-substituted porphyrin dyes employed as sensitizers in dye-sensitized solar cells. Five di-chromophoric zinc porphyrin dyes with the same porphyrin core, a carbazole unit attached in the meso-position through a phenylethenyl linkage, and substituents spanning a range of electron affinities, in an attempt to tune the electronic level of the carbazole unit, have been synthesized (CZPs). Density functional theory (DFT) calculations predicted the nature of the electronic transitions observed in the CZP systems, showing a large degree of orbital mixing. In contrast, …


A Novel Codoping Approach For Enhancing The Performance Of Polypyrrole Cathode In A Bioelectric Battery, Yang Yang, Caiyun Wang, Chunming Zhang, Dan Wang, Dannong He, Gordon G. Wallace Jan 2014

A Novel Codoping Approach For Enhancing The Performance Of Polypyrrole Cathode In A Bioelectric Battery, Yang Yang, Caiyun Wang, Chunming Zhang, Dan Wang, Dannong He, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

A conducting polymer (CP) based bioelectric battery provides a promising alternative to commercial lithium batteries to drive biomedical devices. However, the low power density limits practical application. Here, we synthesize a polypyrrole (PPy)/anthraquinone sulfonate (AQS)/reduced graphene oxide (r-GO) composite via a facile electrochemical route, and use this as a novel cathode material for bioelectric batteries. The presence of r-GO significantly enhanced the electrochemical properties of PPy and led to greatly improved cell performance compared to that of PPy/AQS. The resultant PPy/AQS/r-GO composite delivered a maximum power density of 6240.5 mW m(-2), 14.2 times higher than that of PPy/p-toluenesulfonate (pTS) as …


Fabrication Of Graphene Foam Supported Carbon Nanotube/Polyaniline Hybrids For High-Performance Supercapacitor Applications, Hongxia Yang, Nan Wang, Qun Xu, Zhimin Chen, Yumei Ren, Joselito M. Razal, Jun Chen Jan 2014

Fabrication Of Graphene Foam Supported Carbon Nanotube/Polyaniline Hybrids For High-Performance Supercapacitor Applications, Hongxia Yang, Nan Wang, Qun Xu, Zhimin Chen, Yumei Ren, Joselito M. Razal, Jun Chen

Australian Institute for Innovative Materials - Papers

A large-scale, high-powered energy storage system is crucial for addressing the energy problem. The development of high-performance materials is a key issue in realizing the grid-scale applications of energy-storage devices. In this work, we describe a simple and scalable method for fabricating hybrids (graphenepyrrole/ carbon nanotube-polyaniline (GPCP)) using graphene foam as the supporting template. Graphene-pyrrole (G-Py) aerogels are prepared via a green hydrothermal route from two-dimensional materials such as graphene sheets, while a carbon nanotube/polyaniline (CNT/PANI) composite dispersion is obtained via the in situ polymerization method. The functional nanohybrid materials of GPCP can be assembled by simply dipping the prepared …


Star-Crossed Cube: An Alternative To Star Graph, Nibedita Adhikari, Chitta Ranjan Tripathy Jan 2014

Star-Crossed Cube: An Alternative To Star Graph, Nibedita Adhikari, Chitta Ranjan Tripathy

Turkish Journal of Electrical Engineering and Computer Sciences

This paper introduces a new interconnection network topology called the star-crossed cube (SCQ). The SCQ is observed to be superior to other contemporary networks in terms of various topological parameters such as diameter, cost, average distance, and message traffic density. The various performance metrics of the proposed network, including cost effectiveness and time-cost effectiveness, are found to be better. The optimal routing and broadcasting algorithms for the new network are also presented. Embedding properties for the proposed network are also studied.