Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

PDF

University of Wollongong

Series

2015

Energy

Articles 1 - 10 of 10

Full-Text Articles in Physical Sciences and Mathematics

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 Jan 2015

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 …


Flexible Free-Standing Graphene Paper With Interconnected Porous Structure For Energy Storage, Kewei Shu, Caiyun Wang, Sha Li, Chen Zhao, Yang Yang, Hua-Kun Liu, Gordon G. Wallace Jan 2015

Flexible Free-Standing Graphene Paper With Interconnected Porous Structure For Energy Storage, Kewei Shu, Caiyun Wang, Sha Li, Chen Zhao, Yang Yang, Hua-Kun Liu, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

A novel porous graphene paper is prepared via freeze drying a wet graphene oxide gel, followed by thermal and chemical reduction. The macroscopic structure of the formed graphene paper can be tuned by the water content in the gel precursor. With 92% water content, an interconnected macroporous network can be formed. This porous graphene (PG) paper exhibits excellent electrochemical properties. It can deliver a high discharge capacity of 420 mA h g−1 at a current density of 2000 mA g−1 when used as binder-free lithium ion battery anode. PG paper exhibits a specific capacitance of 137 F g …


3d Hierarchical Porous Graphene Aerogel With Tunable Meso-Pores On Graphene Nanosheets For High-Performance Energy Storage, Long Ren, K N. Hui, K S. Hui, Yundan Liu, Xiang Qi, Jianxin Zhong, Yi Du, Jianping Yang Jan 2015

3d Hierarchical Porous Graphene Aerogel With Tunable Meso-Pores On Graphene Nanosheets For High-Performance Energy Storage, Long Ren, K N. Hui, K S. Hui, Yundan Liu, Xiang Qi, Jianxin Zhong, Yi Du, Jianping Yang

Australian Institute for Innovative Materials - Papers

New and novel 3D hierarchical porous graphene aerogels (HPGA) with uniform and tunable mesopores (e.g., 21 and 53 nm) on graphene nanosheets (GNS) were prepared by a hydrothermal self-assembly process and an in-situ carbothermal reaction. The size and distribution of the meso-pores on the individual GNS were uniform and could be tuned by controlling the sizes of the Co3O4 NPs used in the hydrothermal reaction. This unique architecture of HPGA prevents the stacking of GNS and promises more electrochemically active sites that enhance the electrochemical storage level significantly. HPGA, as a lithium-ion battery anode, exhibited superior electrochemical performance, including a …


Flexible Electrodes And Electrolytes For Energy Storage, Caiyun Wang, Gordon G. Wallace Jan 2015

Flexible Electrodes And Electrolytes For Energy Storage, Caiyun Wang, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

The advent of flexible, wearable electronics has placed new demands on energy storage systems. The demands for high energy density achieved through the use of highly conducting materials with high surface area that enable facile electrochemical processes must now be coupled with the need for robustness and flexibility in each of the components: electrodes and electrolytes. This perspective provides an overview of materials and fabrication protocols used to produce flexible electrodes and electrolytes. We also discuss the key challenges in the development of high performance flexible energy storage devices. Only selected references are used to illustrate the myriad of developments …


Harvesting Temperature Fluctuations As Electrical Energy Using Torsional And Tensile Polymer Muscles, Shi Hyeong Kim, Marcio Dias Lima, Mikhail E. Kozlov, Carter S. Haines, Geoffrey M. Spinks, Shazed Aziz, Changsoon Choi, Hyeon Jun Sim, Xuemin Wang, Hongbing Lu, Dong Qian, John D. W Madden, Ray H. Baughman, Seon Jeong Kim Jan 2015

Harvesting Temperature Fluctuations As Electrical Energy Using Torsional And Tensile Polymer Muscles, Shi Hyeong Kim, Marcio Dias Lima, Mikhail E. Kozlov, Carter S. Haines, Geoffrey M. Spinks, Shazed Aziz, Changsoon Choi, Hyeon Jun Sim, Xuemin Wang, Hongbing Lu, Dong Qian, John D. W Madden, Ray H. Baughman, Seon Jeong Kim

Australian Institute for Innovative Materials - Papers

Diverse means have been deployed for harvesting electrical energy from mechanical actuation produced by low-grade waste heat, but cycle rate, energy-per-cycle, device size and weight, or cost have limited applications. We report the electromagnetic harvesting of thermal energy as electrical energy using thermally powered torsional and tensile artificial muscles made from inexpensive polymer fibers used for fishing line and sewing thread. We show that a coiled 27 μm-diameter nylon muscle fiber can be driven by 16.7 °C air temperature fluctuations to spin a magnetic rotor to a peak torsional rotation speed of 70 000 rpm for over 300 000 heating-cooling …


Harvesting Temperature Fluctuations As Electrical Energy Using Torsional And Tensile Polymer Muscles, Shi Hyeong Kim, Marcio Dias Lima, Mikhail E. Kozlov, Carter S. Haines, Geoffrey M. Spinks, Shazed Aziz, Changsoon Choi, Hyeon Jun Sim, Xuemin Wang, Hongbing Lu, Dong Qian, John D. W Madden, Ray H. Baughman, Seon Jeong Kim Jan 2015

Harvesting Temperature Fluctuations As Electrical Energy Using Torsional And Tensile Polymer Muscles, Shi Hyeong Kim, Marcio Dias Lima, Mikhail E. Kozlov, Carter S. Haines, Geoffrey M. Spinks, Shazed Aziz, Changsoon Choi, Hyeon Jun Sim, Xuemin Wang, Hongbing Lu, Dong Qian, John D. W Madden, Ray H. Baughman, Seon Jeong Kim

Australian Institute for Innovative Materials - Papers

Diverse means have been deployed for harvesting electrical energy from mechanical actuation produced by low-grade waste heat, but cycle rate, energy-per-cycle, device size and weight, or cost have limited applications. We report the electromagnetic harvesting of thermal energy as electrical energy using thermally powered torsional and tensile artificial muscles made from inexpensive polymer fibers used for fishing line and sewing thread. We show that a coiled 27 μm-diameter nylon muscle fiber can be driven by 16.7 °C air temperature fluctuations to spin a magnetic rotor to a peak torsional rotation speed of 70 000 rpm for over 300 000 heating-cooling …


Effects Of Nanostructure On Clean Energy: Big Solutions Gained From Small Features, Jinyan Xiong, Chao Han, Zhen Li, S X. Dou Jan 2015

Effects Of Nanostructure On Clean Energy: Big Solutions Gained From Small Features, Jinyan Xiong, Chao Han, Zhen Li, S X. Dou

Australian Institute for Innovative Materials - Papers

The increasing energy consumption and environmental concerns have driven the development of cost-effective, high-efficiency clean energy. Advanced functional nanomaterials and relevant nanotechnologies are playing a crucial role and showing promise in resolving some energy issues. In this view, we focus on recent advances of functional nanomaterials in clean energy applications, including solar energy conversion, water splitting, photodegradation, electrochemical energy conversion and storage, and thermoelectric conversion, which have attracted considerable interests in the regime of clean energy.


Nanocomposite Hydrogels: Fracture Toughness And Energy Dissipation Mechanisms, Andrea Klein, Philip G. Whitten, Katharina Resch, Gerald Pinter Jan 2015

Nanocomposite Hydrogels: Fracture Toughness And Energy Dissipation Mechanisms, Andrea Klein, Philip G. Whitten, Katharina Resch, Gerald Pinter

Australian Institute for Innovative Materials - Papers

In this study, fracture toughness of nanocomposite hydrogels is quantified, and active mechanisms for dissipation of energy of nanocomposite hydrogels are ascertained. Poly(N,N-dimethylacrylamide) nanocomposite hydrogels are prepared by in situ free radical polymerization with the incorporation of Laponite, a hectorite synthetic clay. Transmission electron microscopy proves exfoliation of clay platelets that serve as multifunctional crosslinkers in the created physical network. Extraordinary high fracture energies of up to 6800 J m-2 are determined by the pure shear test approach, which shows that these soft and stretchable hydrogels are insensitive to notches. In contrast to single- and double-network hydrogels, dynamic mechanic analysis …


Porous Nanoarchitectures Of Spinel-Type Transition Metal Oxides For Electrochemical Energy Storage Systems, Min-Sik Park, Jeonghun Kim, Ki Jae Kim, Jongwon Lee, Jung Ho Kim, Yusuke Yamauchi Jan 2015

Porous Nanoarchitectures Of Spinel-Type Transition Metal Oxides For Electrochemical Energy Storage Systems, Min-Sik Park, Jeonghun Kim, Ki Jae Kim, Jongwon Lee, Jung Ho Kim, Yusuke Yamauchi

Australian Institute for Innovative Materials - Papers

Transition metal oxides possessing two kinds of metals (denoted as AxB3-xO4, which is generally defined as a spinel structure; A, B = Co, Ni, Zn, Mn, Fe, etc.), with stoichiometric or even non-stoichiometric compositions, have recently attracted great interest in electrochemical energy storage systems (ESSs). The spinel-type transition metal oxides exhibit outstanding electrochemical activity and stability, and thus, they can play a key role in realising cost-effective and environmentally friendly ESSs. Moreover, porous nanoarchitectures can offer a large number of electrochemically active sites and, at the same time, facilitate transport of charge carriers (electrons and ions) during energy storage reactions. …


Nano-Carbon Electrodes For Thermal Energy Harvesting, Mark S. Romano, Joselito M. Razal, Dennis Antiohos, Gordon G. Wallace, Jun Chen Jan 2015

Nano-Carbon Electrodes For Thermal Energy Harvesting, Mark S. Romano, Joselito M. Razal, Dennis Antiohos, Gordon G. Wallace, Jun Chen

Australian Institute for Innovative Materials - Papers

Thermogalvanic cells are capable of converting waste heat (generated as a by-product of almost all human activity) to electricity. These devices may alleviate the problems associated with the use of fossil fuels to meet the world's current demand for energy. This review discusses the developments in thermogalvanic systems attained through the use of nano-carbons as the electrode materials. Advances in cell design and electrode configuration that improve performance of these thermo converters and make them applicable in a variety of environments are also summarized. It is the aim of this review to act as a channel for further developments in …