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Synthesis And Characterization Of High Surface Area Molybdenum Nitride Electrodes For High Energy Density Electrochemical Storage Devices
Download Synthesis And Characterization Of High Surface Area Molybdenum Nitride Electrodes For High Energy Density Electrochemical Storage Devices full books in PDF, epub, and Kindle. Read online Synthesis And Characterization Of High Surface Area Molybdenum Nitride Electrodes For High Energy Density Electrochemical Storage Devices ebook anywhere anytime directly on your device. Fast Download speed and no annoying ads. We cannot guarantee that every ebooks is available!
Book Synopsis Synthesis and Characterization of High Surface Area Molybdenum Nitride Electrodes for High Energy Density Electrochemical Storage Devices by : Scott Lee Roberson
Download or read book Synthesis and Characterization of High Surface Area Molybdenum Nitride Electrodes for High Energy Density Electrochemical Storage Devices written by Scott Lee Roberson and published by . This book was released on 1997 with total page 394 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Synthesis and Characterization of High Surface Area Three Dimensional Mesoporous Electrodes by : Roger Campbell
Download or read book Synthesis and Characterization of High Surface Area Three Dimensional Mesoporous Electrodes written by Roger Campbell and published by . This book was released on 2008 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Dissertation Abstracts International by :
Download or read book Dissertation Abstracts International written by and published by . This book was released on 1998 with total page 716 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Fabrication and Characterization of High Surface Area Gold Electrodes by : Madhura S. Damle
Download or read book Fabrication and Characterization of High Surface Area Gold Electrodes written by Madhura S. Damle and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: High surface area gold electrodes are very good substrates for biosensors, catalysis and drug delivery. Their performance is characterized by good sensitivity, low detection limit and high signal. As a result, extensive research is being carried out in this field using different approaches of fabrication to generate high surface area porous electrodes of different morphology, pore size and structure. The morphology of the electrodes can be changed based on whether the approach involves a template or not, types of metal deposition, method and time of dealloying etc. The deposition of metal can be carried out using various approaches such as electroless deposition, electrochemical deposition, combination of electroless and electrochemical deposition, pulsed laser deposition, laser deposition etc. These electrodes can then be used in electrochemical measurements and their performance compared with an unmodified flat gold electrode. We used a template based approach, combined with electrochemical deposition, to fabricate macroporous, macro-nanoporous and nanoporous gold electrodes. To generate nanopores, in case of macro-nanoporous and nanoporous gold electrodes, we used gold-silver alloy electrochemical deposition method, followed by chemical dealloying. The morphology of electrodes was later observed under HITACHI Scanning Electron Microscope (SEM) and their elemental composition studied using HITACHI Energy Dispersion Spectroscopy (EDS). The electrodes were used in electrochemical measurements and their voltammetric data was compared. These measurements involved the determination of surface area, faradaic current using redox molecules with fast and slow electron transfer and charging current in KCl. Surface adsorption of dopamine was studied and detection of dopamine in the presence of ascorbic acid was carried out.
Book Synopsis Electrophoretic Preparation and Characterization of High Surface Area Electrodes from Diamond Nanoparticles by :
Download or read book Electrophoretic Preparation and Characterization of High Surface Area Electrodes from Diamond Nanoparticles written by and published by . This book was released on 2008 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Synthesis and Characterization of Nanostructured Electrodes for Solid State Ionic Devices by : Yuelan Zhang
Download or read book Synthesis and Characterization of Nanostructured Electrodes for Solid State Ionic Devices written by Yuelan Zhang and published by . This book was released on 2006 with total page 182 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ceria is a very important catalytic material for fuel reforming in SOFCs and CO poisoning in PEM fuel cells. Especially, the design of a new generation SOFC requires the in-situ reforming of hydrocarbon fuels. In this work, nanostructured ceria was developed via a controlled hydrothermal process in a mixed water-ethanol medium. The microstructure, formation mechanism, and their surface catalytic properties were investigated.
Book Synopsis F-MWCNT/Mn/Co-oxide Electrodes for Use in High Energy-density Electrochemical Pseudocapacitors by : Iakiv Rozenblit
Download or read book F-MWCNT/Mn/Co-oxide Electrodes for Use in High Energy-density Electrochemical Pseudocapacitors written by Iakiv Rozenblit and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "Despite advancement in the field, energy storage technology has plateaued in recent years. With Li-ion batteries likely reaching the peak of their capability, researchers are developing new technologies such as supercapacitors and other hybrid energy storage devices. Current electrodes for supercapacitors consist primarily of carbon material, such as activated carbon, graphite, graphene, and functionalized multi-walled carbon nanotubes (f-MWCNT). f-MWCNTs are a promising nanomaterial due to their high power density, low cost, low toxicity, high stability, good electrical conductivity, and high active specific surface area (area per mass). The major disadvantage of MWCNT supercapacitors is their lower energy density relative to commercial batteries. However, the addition of metal oxides such as MnO and CoO to f-MWCNT electrodes, can provide a cost-effective energy density boost to supercapacitors through pseudocapacitive effects, while still maintaining the attractive properties of pure f-MWCNT electrodes. This thesis investigates charge storage/delivery properties of Mn/Co-oxides with the aim of using them to functionalize f-MWCNTs and increase the electrode material capacitance.It was found that by functionalizing f-MWCNT with Mn/Co-oxides, a significant increase in specific capacitance was achieved. In galvanostatic charge/discharge (GCD) tests run at 0.2 mA/cm2 the f-MWCNT yielded 288±10F/g, while the Mn0.5/Co0.5-oxide/f-MWCNT electrode yielded 430±14 F/g. Cyclic voltammetry (CV) tests yielded even higher values at low scan rate, 752±85 F/g. It was also found that pure Mn0.5/Co0.5-oxide behaves more as a battery electrode material than as a supercapacitor electrode material, yielding apparent capacitance of 4497±57 mF/cm2 (1.38mAh/cm2). The high apparent capacitance (e.g. energy storage and delivery) was due to intercalation of cations (Na+ or Li+) into the crystalline structure of the Mn0.5/Co0.5-oxide phase in order to compensate the redox transition change. However, the Mn0.5/Co0.5-oxide/f-MWCNT electrodes were not found to enable cation intercalation, and the resulting capacitance was lower (752±85 F/g). All samples showed high stability and highly porous microstructure. Metal oxides were found to consist of MnO, MnO2, CoO, Co3O4 and metal hydroxides." --
Book Synopsis Electrode Materials for Energy Storage and Conversion by : Mesfin A. Kebede
Download or read book Electrode Materials for Energy Storage and Conversion written by Mesfin A. Kebede and published by CRC Press. This book was released on 2021-11-17 with total page 518 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a comprehensive overview of the latest developments and materials used in electrochemical energy storage and conversion devices, including lithium-ion batteries, sodium-ion batteries, zinc-ion batteries, supercapacitors and conversion materials for solar and fuel cells. Chapters introduce the technologies behind each material, in addition to the fundamental principles of the devices, and their wider impact and contribution to the field. This book will be an ideal reference for researchers and individuals working in industries based on energy storage and conversion technologies across physics, chemistry and engineering. FEATURES Edited by established authorities, with chapter contributions from subject-area specialists Provides a comprehensive review of the field Up to date with the latest developments and research Editors Dr. Mesfin A. Kebede obtained his PhD in Metallurgical Engineering from Inha University, South Korea. He is now a principal research scientist at Energy Centre of Council for Scientific and Industrial Research (CSIR), South Africa. He was previously an assistant professor in the Department of Applied Physics and Materials Science at Hawassa University, Ethiopia. His extensive research experience covers the use of electrode materials for energy storage and energy conversion. Prof. Fabian I. Ezema is a professor at the University of Nigeria, Nsukka. He obtained his PhD in Physics and Astronomy from University of Nigeria, Nsukka. His research focuses on several areas of materials science with an emphasis on energy applications, specifically electrode materials for energy conversion and storage.
Book Synopsis American Doctoral Dissertations by :
Download or read book American Doctoral Dissertations written by and published by . This book was released on 1997 with total page 806 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis 2D Metal Carbides and Nitrides (MXenes) by : Babak Anasori
Download or read book 2D Metal Carbides and Nitrides (MXenes) written by Babak Anasori and published by Springer Nature. This book was released on 2019-10-30 with total page 534 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes the rapidly expanding field of two-dimensional (2D) transition metal carbides and nitrides (MXenes). It covers fundamental knowledge on synthesis, structure, and properties of these new materials, and a description of their processing, scale-up and emerging applications. The ways in which the quickly expanding family of MXenes can outperform other novel nanomaterials in a variety of applications, spanning from energy storage and conversion to electronics; from water science to transportation; and in defense and medical applications, are discussed in detail.
Book Synopsis Novel Mesoporous Nano-titania/carbon Composite Electrodes for Electrochemical Energy Storage by : Micah Sussman
Download or read book Novel Mesoporous Nano-titania/carbon Composite Electrodes for Electrochemical Energy Storage written by Micah Sussman and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "The development of novel scalable nanoscale materials and fabrication techniques for high performance TiO2 Li-ion electrodes is investigated in this thesis. The development and study of the novel fabrication methods is approached from the stand point of a binder-free electrode, and its comparison to standard binder-basedelectrodes, making use of commercial P25 TiO2 product as active material. The characterization of novel titania synthesized by manipulating the parameters of anaqueous process, is performed for two phases of TiO2, namely anatase and brookite, based on comprehensive nanocrystal morphological and electrochemical property assessment. Finally all is brought together by investigating the application of the novel fabrication protocol to the aqueous synthesized anatase to engineer binderfree 3-dimensional electrodes, and studying their Li-ion intercalation performance. The fabrication of binder-free P25 nanotitania/carbon composite electrodes is pursued via formulating pastes and controlled sintering yielding enhanced electrochemical performance in comparison to standard binder-based methods using thesame active and conductive components. The new paste formulation and sintering sequence provides a significant increase in dispersion of carbon due to smaller agglomerate size resulting in enhanced inter-particle (active-conduction) mixing and packing density than standard binder-based electrodes. Cyclic voltammetry and galvanostatic charge/discharge proved that the binder-free electrodes possess improved conductivity, specific capacity, and reversibility, as compared to binderbased electrodes. Most significantly, the capacity retention of the binder-free electrode was much higher than that of the binder-based electrode at 94 and 53%, respectively. Using an aqueous solution based synthesis process, 2-dimensional brookite nanoplatelets and 6 nm anatase nanoparticles are obtained and examined for their physical and electrochemical properties as Li-ion host materials. Brookite, itself is particularly interesting, as it is the least understood of the nanoscale TiO2 phases, especially in the form of 2-D crystal structures that are deemed advantageous for Liion diffusion. This study provides insight into the lithiation mechanism of brookite, concluding that a solid-solution is formed upon lithiation corresponding to Li0.5TiO2 that is isostructural with brookite. Further, the brookite nanoplatelets are discovered to undergo unique crystal structure enhancement upon cycling that allows them to quickly relax upon delithiation in an extremely efficient (>99.7% Coulombic efficiency) reversible manner translating to excellent Li-ion intercalation stability. Anatase nanoparticle are described in terms of crystallinity and surface area. As prepared anatase has low crystallinity (70%), but high surface area (222 m2 g−1), and when annealed at 300 °C, the crystallinity increases to 90% but the surface area drops to 120 m2 g−1. Electrochemically, this allows the annealed sample with higher crystallinity to increase its diffusion-based lithium insertion capability, thus giving it high capacity at low rate, and comparable capacity at high rate to theas-prepared anatase, whose high surface area allows for increased pseudocapacitive type storage. These results point to the importance of tailoring anatase's properties (crystallinity vs. surface-area) depending on the desired performance: long-term cycling life at low rate vs. high rate capability at lower capacity retention. Finally, the novel fabrication method is combined with the aqueous synthesized anatase, and self-supporting 3-dimensional electrodes are investigated. It is demonstrated that the 3-D electrodes fabricated using the novel paste formulation and controlled sintering protocols provide a highly conducting percolating network of carbon along with inter-particle necking resulting in optimum active material/carbon/electrolyte interfacing for facile lithium insertion. Electrochemical tests show that 3-D electrodes have significantly higher capacity over their standard counterparts (180 versus 150 mA h g−1), and also good capacity retention at high rate. The newly developed 3-D electrode fabrication concept can provide a fertile platform for superior Li-ion intercalation electrodes involving other than nanotitania anode and cathode materials." --
Book Synopsis Nickel-oxide-based Electrodes for Energy Storage Applications by : Abraham Gomez Vidales
Download or read book Nickel-oxide-based Electrodes for Energy Storage Applications written by Abraham Gomez Vidales and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "This Ph.D. thesis presents a comprehensive study on the use of nickel-oxide-based electrodes for energy storage applications, focusing specifically on cathodes for production of hydrogen by water electrolysis and electrodes for electrochemical supercapacitors. The main objective of this research was to develop Ni-oxide-based materials (Ni-Co-oxide, Ni-Mo-oxide, and Ni-Mo-Ir-oxide) to achieve (i) high electrocatalytic activity and long-term performance stability in the hydrogen evolution reaction (HER), and (ii) high energy storage capacity under various operating conditions (i.e. metal oxide composition, electrolyte type, pH, and temperature).The Ni-oxide based coatings of various compositions were fabricated on a titanium substrate through a thermal-salt decomposition method. The coatings were characterized by several surface-characterization techniques, such as X-ray photoelectron spectroscopy (XPS), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), and scanning electron microscopy (SEM), to know their chemical composition, structure, and morphology. At the same time, electrochemical techniques such as linear Tafel polarization (LTP), cyclic voltammetry (CV), chronoamperometry (CA), chronopotentiometry (CP), and galvanostatic charge-discharge (GCD) were employed to determine their electrochemical activity, active surface area, long-term stability, and charge-discharge capacity.First, the electrocatalytic activity of Ni-Co-oxide cathodes of various compositions for HER in acidic and alkaline media was studied. The electrodes were found to be of a semi-crystalline structure, yielding a surface morphology characterized by a relatively high surface roughness factor (up to 25). The Ni0.2Co0.8-oxide was identified as the best electrode material candidate, due to the surface-area effect. Furthermore, it showed a significantly higher electrocatalytic stability compared to Ni. However, its intrinsic activity was found to be lower than that of the control sample (pure metal nickel).The electrocatalytic properties of Ni-Mo-oxides for hydrogen production in acidic, alkaline, and neutral electrolytes were studied next. These oxides showed a better performance than pure nickel, and they were stable in the whole pH scale, even during long-term electrolysis in an acidic medium. The most extrinsically active coating was found to be Ni0.6Mo0.4-oxide (in all three electrolytes), and this coating showed the highest intrinsic activity in the neutral electrolyte. In the acidic and alkaline electrolytes, the Ni0.8Mo0.2-oxide coating was found to be the most intrinsically active. This superior performance was attributed to an increase in the electrochemically active surface area, as well as the electrochemical activity of the material.Considering the excellent results obtained with the Ni-Mo-oxide electrodes (specifically the Ni0.6-Mo0.4-oxide coating, which was the best performing composition), the addition of iridium (an excellent but expensive catalyst) was investigated for hydrogen production and in the development of electrodes for supercapacitors.In all the cases, the Ni-Mo-Ir-oxide showed a better performance in an acidic medium when compared to nickel for HER. These results were attributed to both the increase of surface area and a possible modification of the electronic structure of the coatings. In addition, deactivation/re-activation experiments were done in the presence of the most common impurities found in commercial electrolytes during hydrogen production (Cu, Fe, Cu + Fe). These experiments showed that the Ni-Mo-Ir- electrodes were much more resistant to deactivation and can be, in addition, reactivated to a higher activity degree than pure nickel cathodes.Based on the results of this thesis, it was concluded that nickel-oxide-based electrodes are excellent candidates for alternative electrochemical energy storage systems (hydrogen production by water electrolysis and electricity storage in supercapacitors)." --
Book Synopsis High Surface Area Electrode Research by :
Download or read book High Surface Area Electrode Research written by and published by . This book was released on 1996 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: Molybdenum nitride (MOxN (x=l or 2)) films, 15 micron thick, have been deposited via chemical vapor deposition (CVD) on 50 micron thick polycrystalline titanium substrates using molybdenum pentachloride (MoCl5) and NH3 in a cold wall reactor with vertical pancake heaters. The surface morphology of the films was slightly porous but did not contain the large cracks typical of high surface area MOxN films prepared by conversion of MoO3. Debye-Scherrer calculations indicate that the average particle size of the films was approximately 50 nm. The CvD MOxN films had a two-phase structure which appeared to be 60% d-MoN and 40% g-Mo2N. Energy dispersive X-ray (EDX) data did not reveal the presence of oxygen and chlorine in films deposited above 6000 C. Electrode evaluation via AC impedance spectroscopy and cyclic voltammetry indicates that CVD films were capacitive with a voltage stability of 0.9 volts in 6.4M KOH.
Book Synopsis Novel Design and Synthesis of Transition Metal Hydroxides and Oxides for Energy Storage Device Applications by : Peifeng Li
Download or read book Novel Design and Synthesis of Transition Metal Hydroxides and Oxides for Energy Storage Device Applications written by Peifeng Li and published by . This book was released on 2016 with total page 62 pages. Available in PDF, EPUB and Kindle. Book excerpt: Supercapacitors (SCs) and Li-ion batteries (LIBs) are two types of important electrical energy storage devices with high power density and high energy density respectively. However, to satisfy the increasing demand of high-performance energy storage devices, the energy density of SCs and power/energy densities of LIBs have to be further improved. The exploration, research, and development of electrode materials with high-performance for applications in SCs and LIBs are still needed to meet the ever-increasing demand on energy and power densities. Herein, the amorphous Ni-Co-Mo ternary hydroxides nanoflakes for SCs and oxides nanoflakes for LIBs with ultrathin stature, abundant open spaces, and interconnecting mesoporous were prepared via electrodeposition method and further annealing process, respectively. The as-obtained materials with unique hierarchical structures offer a large electrochemical active area, resulting in a fast ion transportation (OH- in SCs and Li+ in LIBs) electrolyte immersion, as well as provide effective pathways for electron transport. Thus, the as-prepared Ni-Mo-Co triple hydroxides and oxides electrodes exhibit a high specific capacitance /capacity (3074 F g-1 at 2 A g-1 in SCs and 1132.31 mA h g-1 at 0.2 A g-1 in LIBs), remarkable rate performance, as well as long-term cyclability in SCs and LIBs, respectively. Also, the effect of composition of trimetallic hydroxides on SCs performance have been studied, and the performance have been optimized by tuning the feeding ratio of Ni, Mo, and Co. It is found that supreme performance was achieved when feeding ratio Ni/Mo/Co (1/1/0.4).
Book Synopsis Design of Electrode for Electrochemical Energy Storage and Conversion Devices Using Multiwall Carbon Nanotubes by : Seung Woo Lee (Ph. D.)
Download or read book Design of Electrode for Electrochemical Energy Storage and Conversion Devices Using Multiwall Carbon Nanotubes written by Seung Woo Lee (Ph. D.) and published by . This book was released on 2010 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt: All-multiwall carbon nanotube (MWNT) thin films are created by layer-by-layer (LbL) assembly of surface functionalized MWNTs. Negatively and positively charged MWNTs were prepared by surface functionalization, allowing the incorporation of MWNTs into highly tunable thin films via the LbL technique. The pH dependent surface charge on the MWNTs gives this system the unique characteristics of LbL assembly of weak polyelectrolytes, controlling thickness and morphology with assembly pH conditions. We demonstrate that these MWNT thin films have randomly oriented interpenetrating network structure with well developed nanopores using SEM, which is an ideal structure of functional materials for various applications. LbL-MWNT electrodes show high electronic conductivity in comparison with polymer composites with single wall nanotubes, and high capacitive behavior in aqueous electrolyte with precise control of capacity. Of significance, additive-free LbL-MWNT electrodes with thicknesses of several microns can deliver high energy density (200 Wh/kg) at an exceptionally high power of 100 kW/kg in lithium nonaqueous cells. Utilizing the redox reactions on the surface functional groups in a wide voltage window (1.5 - 4.5 V vs. lithium) in nonaqueous electrolytes, asymmetric electrochemical capacitors consisting of LbL-MWNT and either lithium or a lithium titanium oxide negative electrode exhibit gravimetric energy density -5 times higher than conventional electrochemical capacitors with comparable gravimetric power and cycle life. Thin-film LbL-MWNT electrodes could potentially lead to breakthrough power sources for microsystems and flexible electronic devices such as smart cards and ebook readers, while thicker LbL-MWNT electrodes could expand the application of electrochemical capacitors into heavy vehicle and industrial systems, where the ability to deliver high energy at high power will be an enabling technological development. Furthermore, nanoscale pseuduocapactive oxides and electrocatalysts were incorporated into LbL-MWNT electrodes for energy storage and conversion. Inorganic oxides such as MnO2 and RuO2 are incorporated to increase volumetric capacitance in LbLMWNT electrodes using electroless deposition and square wave pulse potential deposition methods. Preliminary results show that we can increase volumetric capacitance of LbLMWNT/ MnO2 and LbL-MWNT/RuO2 composite up to 1000 F/cm3 in aqueous electrolytes. In addition, Pt and Pt/Ru alloy electrocatalysts are introduced into LbL-MWNT electrodes using square wave pulse potential deposition, which show higher CO and methanol oxidation activities. Tailored incorporation of metal and oxide nanoparticles into LbLMWNT electrodes by square wave pulse potential opens a new strategy for novel energy storage and conversion electrodes with superior electrochemical properties.
Book Synopsis Microstructured Electrodes for Electrochemical Energy Storage by : Leland Cramer Smith
Download or read book Microstructured Electrodes for Electrochemical Energy Storage written by Leland Cramer Smith and published by . This book was released on 2015 with total page 202 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lithium-ion batteries and electric double-layer capacitors are two types of electrochemical energy storage devices that are characterized by high energy density and high power density, respectively. While these technologies have been successfully applied in applications such as personal electronics and electric vehicles, the potential for microscale energy storage devices remains unrealized. In this dissertation novel materials and processing methods are introduced for the fabrication of microscale lithium-ion batteries and electric double-layer capacitors. In the area of electric double-layer capacitors, carbon electrodes are fabricated by electrophoretic deposition and self-assembly and paired with a novel solid-state ionogel electrolyte. We successfully fabricate an on-chip electric double-layer capacitor that is just 0.14 mm2 in electrode area, which is about 40 times smaller than any device so far reported in the literature. Microscale lithium-ion battery electrodes are prepared by micro-molding techniques. The composition of the anode and cathode are tuned to maximize mechanical durability, electronic and ionic conductivity. SU-8 photoresist is presented as a novel electrolyte material for conformally patterning 3D anode arrays. Both 2D and 3D lithium-ion batteries using SU-8 are presented. Initial results suggest that a working 3D microbattery based on SU-8 electrolyte is feasible. Finally, more fundamental research is presented on the sol-gel encapsulation of lithium-polysulfide liquid catholytes. By carefully tuning the non-hydrolytic sol-gel reaction, water-reactive lithium-polysulfides are successfully encapsulated to form a polysulfide gel that retains its lithium storage activity. This polysulfide gel is used to fabricate a fully solid-state lithium-sulfur battery.
Book Synopsis Nanostructured Electrodes for High-performance Electrochemical Capacitors by : Qi Lu
Download or read book Nanostructured Electrodes for High-performance Electrochemical Capacitors written by Qi Lu and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Despite significant progresses in the development for high-performance electrochemical capacitors (also called supercapacitor), it lacks techniques to realize the full potential of electrode material by achieving simultaneously tailored pore structure, electrode conductivity, and crystallinity. Moreover, the problem of being difficult for industrial scale manufacture still exists. For an attempt to address all these issues, the scientific properties of nickel oxide as a candidate electrode material were first investigated. The surface and bulk contributions of nickel oxide to charge storage were differentiated and studied. After the scientific principles for designing high-performance supercapacitor electrodes were understood, a simple and cost-effective process, which is also scalable, was developed for achieving supercapacitor electrodes with both high energy and power densities. In the process, metal nanoparticles (Ni and Fe) are first fabricated using a modified polyol method. A simple mechanical compaction of nanoparticles and a followed thermal treatment result in compact, stable, highly porous metal/metal oxide electrodes that do not require a support. During the charging process, OH - electrolytic ions are bound to the oxides, giving off electrons. The process is reversed when the stored electrical energy is drawn off as current. The high granularity oxides provide a large inner surface area, and the conductive network of the metal particles is maintained. As in NiO/Ni nanocomposite electrodes, high energy density of about 60 Wh/kg and power density of 10 kW/kg were simultaneous achieved with a slow charge/fast discharge process.
