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Full-Text Articles in Engineering
Flexible Free-Standing Graphene-Silicon Composite Film For Lithium-Ion Batteries, Jiazhao Wang, Chao Zhong, Shulei Chou, Hua Liu
Flexible Free-Standing Graphene-Silicon Composite Film For Lithium-Ion Batteries, Jiazhao Wang, Chao Zhong, Shulei Chou, Hua Liu
Shulei Chou
Flexible, free-standing, paper-like, graphene-silicon composite materials have been synthesized by a simple, one-step, in-situ filtration method. The Si nanoparticles are highly encapsulated in a graphene nanosheet matrix. The electrochemical results show that graphene-Si composite film has much higher discharge capacity beyond 100 cycles (708 mAh g− 1) than that of the cell with pure graphene (304 mAh g− 1). The graphene functions as a flexible mechanical support for strain release, offering an efficient electrically conducting channel, while the nanosized silicon provides the high capacity.
Nanocrystalline Nio Hollow Spheres In Conjunction With Cmc For Lithium-Ion Batteries, Chao Zhong, Jiazhao Wang, Shulei Chou, Konstantin Konstantinov, Mokhlesur Rahman, Hua Liu
Nanocrystalline Nio Hollow Spheres In Conjunction With Cmc For Lithium-Ion Batteries, Chao Zhong, Jiazhao Wang, Shulei Chou, Konstantin Konstantinov, Mokhlesur Rahman, Hua Liu
Shulei Chou
Hollow spherical NiO particles were prepared using the spray pyrolysis method with different concentrations of precursor. The electrochemical properties of the NiO electrodes, which contained a new type of binder, carboxymethyl cellulose (CMC), were examined for comparison with NiO electrodes with polyvinylidene fluoride (PVDF) binder. The electrochemical performance of NiO electrodes using CMC binder was significantly improved. For the cell made from 0.3 mol L−1 precursor, the irreversible capacity loss between the first discharge and charge is about 43 and 24% for the electrode with PVDF and CMC binder, respectively. The cell with NiO–CMC electrode has a much higher discharge …
Silicon/Single-Walled Carbon Nanotube Composite Paper As A Flexible Anode Material For Lithium Ion Batteries, Shulei Chou, Yue Zhao, Jiazhao Wang, Zhixin Chen, Hua-Kun Liu, S. X. Dou
Silicon/Single-Walled Carbon Nanotube Composite Paper As A Flexible Anode Material For Lithium Ion Batteries, Shulei Chou, Yue Zhao, Jiazhao Wang, Zhixin Chen, Hua-Kun Liu, S. X. Dou
Shulei Chou
Flexible silicon/single-walled carbon nanotube (Si/SWCNT) composite paper was prepared using the pulsed laser deposition (PLD) method to deposit Si onto SWCNT paper. In the composite, Si mainly shows nanoworm-like morphology. Increasing deposition time results in an increased amount of Si microspheres. Electrochemical measurements show that the capacity of the composite paper is improved by the presence of Si. The Si/SWCNT composite with only 2.2% Si shows a capacity of 163 mA h g−1 at a current density of 25 mA g−1 up to 50 cycles, which is more than 60% improvement of the capacity of pristine CNT paper. The Si …
Rapid Synthesis Of Li4ti5o12 Microspheres As Anode Materials And Its Binder Effect For Lithium-Ion Battery, Shulei Chou, Jiazhao Wang, Hua Liu, S. Dou
Rapid Synthesis Of Li4ti5o12 Microspheres As Anode Materials And Its Binder Effect For Lithium-Ion Battery, Shulei Chou, Jiazhao Wang, Hua Liu, S. Dou
Shulei Chou
Li4Ti5O12 microspheres composed of nanoflakes were synthesized within 1 h by a combination of a microwave-assisted hydrothermal method and a microwave postannealing process. The Li4Ti5O12 microspheres were characterized by X-ray diffraction, Brunauer–Emmett–Teller N2 adsorption, scanning electron microscopy, Raman spectroscopy, and transmission electron microscopy. Sodium carboxymethyl cellulose (CMC) was also investigated as a low-cost green binder. The electrochemical tests, including constant current charge–discharge, cyclic voltammetry, and electrochemical impedance spectroscopy, demonstrated that the electrode using CMC as binder had better high-rate capability than the one with polyvinylidene fluoride (PVDF) binder. The electrode using CMC and PVDF as binder had the same lithium …
Silver-Coated Tio2 Nanostructured Anode Materials For Lithium Ion Batteries, - Md. Mokhlesur Rahman, Jiazhao Wang, David Wexler, Yuyuan Zhang, Xinjun Li, Shulei Chou, Hua Liu
Silver-Coated Tio2 Nanostructured Anode Materials For Lithium Ion Batteries, - Md. Mokhlesur Rahman, Jiazhao Wang, David Wexler, Yuyuan Zhang, Xinjun Li, Shulei Chou, Hua Liu
Shulei Chou
Anatase TiO2 nanoribbons/nanotubes (TiO2-NRTs) have been synthesised successfully via a reflux method followed by drying in a vacuum oven, and then, silver-coated TiO2 NRTs (Ag/TiO2-NRTs) were prepared by coating silver particles onto the TiO2-NRTs surface by the traditional silver mirror reaction. The physical properties of the synthesised products were examined in detail using X-ray diffraction, field emission gun scanning electron microscopy, energy-dispersive X-ray spectroscopy, and transmission electron microscopy, respectively. The results indicated that the Ag nanoparticles were uniformly deposited on the surface of the TiO2 nanoribbons/nanotubes. The electrochemical properties were investigated …
Nanocrystalline Porous A-Life02-C Composite-An Environmentally Friendly Cathode For The Lithium-Ion Battery, Md Mokhlesur Rahman, Jiazhao Wang, Mohd Faiz Hassan, Shulei Chou, Zhixin Chen, Hua Liu
Nanocrystalline Porous A-Life02-C Composite-An Environmentally Friendly Cathode For The Lithium-Ion Battery, Md Mokhlesur Rahman, Jiazhao Wang, Mohd Faiz Hassan, Shulei Chou, Zhixin Chen, Hua Liu
Shulei Chou
A novel nanocrystalline porous α-LiFeO2–C composite with a high surface area of around 115 m2 g−1 has been synthesized by a simple molten salt method, followed by a carbon coating process. The structure and morphology were confirmed by X-ray diffraction, field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). FE-SEM observations demonstrated that the morphology consists of α-LiFeO2–C nanoclusters composed of very tiny nanoparticles joined together by a porous architecture. TEM investigations revealed that amorphous carbon was incorporated into the pores among the nanoparticles and that some nanoparticles were covered by a thin layer of carbon as well. …
Electrochemical Deposition Of Porous Vox And Mno2 Nanowires On Stainless Steel Mesh For Flexible Supercapacitors, Shulei Chou, Jiazhao Wang, Hua Liu, S Dou
Electrochemical Deposition Of Porous Vox And Mno2 Nanowires On Stainless Steel Mesh For Flexible Supercapacitors, Shulei Chou, Jiazhao Wang, Hua Liu, S Dou
Shulei Chou
Porous vanadium oxide (VOx) and MnO2 nanowires were synthesized by an electrochemical deposition method using stainless steel mesh as substrate. The as-prepared porous VOx and MnO2 nanowire films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and Raman spectroscopy. The cyclic voltammetry (CV) results show that the MnO2 nanowire film shows specific capacitance of 195, 170, 158, and 91 F g-1 at scan rates of 5, 10, 20, and 50 mV s-1, respectively. The porous VOx film displays specific capacitance of 152, 124, 99, and 76 F g …
Electrodeposition Of Mno2 Nanowires On Carbon Nanotube Paper As Free-Standing, Flexible Electrode For Supercapacitors, Shulei Chou, Jia-Zhao Wang, Sau-Yen Chew, Hua Liu, S Dou
Electrodeposition Of Mno2 Nanowires On Carbon Nanotube Paper As Free-Standing, Flexible Electrode For Supercapacitors, Shulei Chou, Jia-Zhao Wang, Sau-Yen Chew, Hua Liu, S Dou
Shulei Chou
MnO2 nanowires were electrodeposited onto carbon nanotube (CNT) paper by a cyclic voltametric technique. The as-prepared MnO2 nanowire/CNT composite paper (MNCCP) can be used as a flexible electrode for electrochemical supercapacitors. Electrochemical measurements showed that the MNCCP electrode displayed specific capacitances as high as 167.5 F g-1 at a current density of 77 mA g-1. After 3000 cycles, the composite paper can retain more than 88% of initial capacitance, showing good cyclability. The CNT paper in the composite acted as a good conductive and active substrate for flexible electrodes in supercapacitors, and the nanowire structure of the MnO2 could facilitate …
Nickel Sulfide Cathode In Combination With An Ionic Liquid-Based Electrolyte For Rechargeable Lithium Batteries, Jiazhao Wang, Shulei Chou, Sau Yen Chew, Jiazeng Sun, Maria Forsyth, Douglas Macfarlane, Hua Liu
Nickel Sulfide Cathode In Combination With An Ionic Liquid-Based Electrolyte For Rechargeable Lithium Batteries, Jiazhao Wang, Shulei Chou, Sau Yen Chew, Jiazeng Sun, Maria Forsyth, Douglas Macfarlane, Hua Liu
Shulei Chou
Nickel sulfides, pure Ni3S2 and a mixture of Ni7S6-NiS, were synthesized through a solvothermal process. The nickel sulphide powders were characterised by X-ray diffraction, scanning electron microscopy, and electrochemical testing. The results showed that the capacity of NiS-Ni7S6 is much higher than that of Ni3S2, when used as the cathode in a lithium cell with an organic solvent-based electrolyte, 1 M lithium bis (trifluoromethanesulfonyl)amide (LiNTf2) in poly(ethylene glycol) dimethyl either 500. The NiS-Ni7S6 electrodes were also tested with an ionic liquid electrolyte consisting of 1 M LiNTf2 in N-methyl-N-propyl pyrrolidinium bis(trifioromethanesulfonyl)amide ([C3mpyr][NTf2]) to compare with organic-solvent based electrolytes. The result …
Electrochemical Deposition Of Porous Co3o4 Nanostructured Thin Film For Lithium-Ion Battery, Shulei Chou, Jiazhao Wang, Hua Liu, S. Dou
Electrochemical Deposition Of Porous Co3o4 Nanostructured Thin Film For Lithium-Ion Battery, Shulei Chou, Jiazhao Wang, Hua Liu, S. Dou
Shulei Chou
Porous Co3O4 nanostructured thin films are electrodeposited by controlling the concentration of Co(NO3)2 aqueous solution on nickel sheets, and then sintered at 300C for 3 h. The as-prepared thin films are characterised by thermogravimetric analysis (TGA), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The electrochemical measurements show that the highly porous Co3O4 thin film with the highest electrochemically active specific surface area (68.64 m2 g-1) yields the best electrochemical performance compared with another, less-porous film and with a non-porous film. The highest specific capacity (513 mAh g-1 after 50 cycles) is obtained from the thinnest film with Co3O4 loaded …
The Compatibility Of Transition Metal Oxide/Carbon Composite Anode And Ionic Liquid Electrolyte For The Lithium-Ion Battery, Shulei Chou, Lin Lu, Jiazhao Wang, Md Mokhlesur Rahman, Chao Zhong, Hua Liu
The Compatibility Of Transition Metal Oxide/Carbon Composite Anode And Ionic Liquid Electrolyte For The Lithium-Ion Battery, Shulei Chou, Lin Lu, Jiazhao Wang, Md Mokhlesur Rahman, Chao Zhong, Hua Liu
Shulei Chou
Three types of transition metal oxide/carbon composites including Fe2O3/C, NiO/C and CuO/Cu2O/C synthesized via spray pyrolysis were used as anode for lithium ion battery application in conjunction with two types of ionic liquid: 1 M LiN(SO2CF3)2 (LiTFSI) in 1-ethyl-3-methyl-imidazolium bis(fluorosulfonlyl)imide (EMI-FSI) or 1-methyl-1-propylpyrrolidinium bis(fluorosulfonyl)imide (Py13-FSI). From the electrochemical measurements, the composite electrodes using Py13-FSI as electrolyte show much better electrochemical performance than those using EMI-FSI as electrolyte in terms of reversibility. The Fe2O3/C composite shows the highest specific capacity and the best capacity retention (425 mAh g−1) under a current density of 50 mA g−1 for up to 50 cycles, …
Sno2-Coated Multiwall Carbon Nanotube Composite Anode Materials For Rechargeable Lithium-Ion Batteries, Lukman Noerochim, Jiazhao Wang, Shulei Chou, Huijun Li, Hua Liu
Sno2-Coated Multiwall Carbon Nanotube Composite Anode Materials For Rechargeable Lithium-Ion Batteries, Lukman Noerochim, Jiazhao Wang, Shulei Chou, Huijun Li, Hua Liu
Shulei Chou
SnO2-coated multiwall carbon nanotube (MWCNT) nanocomposites were synthesized by a facile hydrothermal method. The as-prepared nanocomposites were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), and thermogravimetric analysis (TGA). The SnO2/MWCNT composites, when combined with carboxymethyl cellulose (CMC) as a binder, show excellent cyclic retention, with the high specific capacity of 473 mAh g−1 beyond 100 cycles, much greater than that of the bare SnO2 which was also prepared by the hydrothermal method in the absence of MWCNTs. The enhanced capacity retention could be mainly attributed to …
Electrochemical Deposition Of Porous Co(Oh)2 Nanoflake Films On Stainless Steel Mesh For Flexible Supercapacitors, Shulei Chou, Jiazhao Wang, Hua-Kun Liu, S. X. Dou
Electrochemical Deposition Of Porous Co(Oh)2 Nanoflake Films On Stainless Steel Mesh For Flexible Supercapacitors, Shulei Chou, Jiazhao Wang, Hua-Kun Liu, S. X. Dou
Shulei Chou
Flexible porous Co(OH)2 nanoflake films were prepared by galvanostatic electrodeposition on lightweight and inexpensive stainless steel mesh. The as-prepared porous Co(OH)2 nanoflake films were characterized by X-ray diffraction, thermogravimetric analysis, and scanning electron microscopy. Electrochemical tests including cyclic voltammetry, constant current charge-discharge, and electrochemical impedance spectroscopy were also used to investigate the electrochemical performance. The results show that the highest capacitance is 609.4 F g-1, the specific capacitance decreases by less than 5% as the mass loading of Co(OH)2 increases by more than 340%, and the specific capacitance only decreases by less than 15% when the current densities increase up …
Highly Flexible And Bendable Free-Standing Thin Film Polymer For Battery Application, Jiazhao Wang, Shulei Chou, Hao Liu, Guoxiu Wang, Chao Zhong, Sau Yen Chew, Hua Liu
Highly Flexible And Bendable Free-Standing Thin Film Polymer For Battery Application, Jiazhao Wang, Shulei Chou, Hao Liu, Guoxiu Wang, Chao Zhong, Sau Yen Chew, Hua Liu
Shulei Chou
Highly flexible and bendable free-standing polypyrrole (PPy) films were prepared using the electrochemical polymerization method. The paper-like films are soft, lightweight, mechanically robust, and highly electrically conductive. The morphologies and electrochemical behaviour of the free-standing pure PPy films were affected by the electrochemical polymerization conditions. The free-standing films show promise as cathodes for flexible and bendable batteries.
Basic Molten Salt Process-A New Route For Synthesis Of Nanocrystalline Li4ti5o12-Tio2 Anode Material For Li-Ion Batteries Using Eutectic Mixture Of Lino3-Lioh-Li2o2, Md Mokhlesur Rahman, Jiazhao Wang, Mohd Hassan, Shulei Chou, David Wexler, Hua Liu
Basic Molten Salt Process-A New Route For Synthesis Of Nanocrystalline Li4ti5o12-Tio2 Anode Material For Li-Ion Batteries Using Eutectic Mixture Of Lino3-Lioh-Li2o2, Md Mokhlesur Rahman, Jiazhao Wang, Mohd Hassan, Shulei Chou, David Wexler, Hua Liu
Shulei Chou
A nanocrystalline Li4Ti5O12–TiO2 duplex phase has been synthesized by a simple basic molten salt process (BMSP) using an eutectic mixture of LiNO3–LiOH–Li2O2 at 400–500 °C. The microstructure and morphology of the Li4Ti5O12–TiO2 product are characterized by means of X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and transmission electron microscopy (TEM). The sample prepared by heat-treating at 300 °C for 3 h (S-1) reveals dense agglomerates of ultra-fine nanocrystalline Li4Ti5O12; with heat treatment at …
Spray Pyrolyzed Nio-C Nanocomposite As An Anode Material For The Lithium-Ion Battery With Enhanced Capacity Retention, - Md. Mokhlesur Rahman, Shulei Chou, Chao Zhong, Jiazhao Wang, David Wexler, Hua Liu
Spray Pyrolyzed Nio-C Nanocomposite As An Anode Material For The Lithium-Ion Battery With Enhanced Capacity Retention, - Md. Mokhlesur Rahman, Shulei Chou, Chao Zhong, Jiazhao Wang, David Wexler, Hua Liu
Shulei Chou
NiO–C nanocomposite was prepared by a spray pyrolysis method using a mixture of Ni(NO3)2 and citric acid solution at 600 °C. The microstructure and morphology of the NiO–C composite were characterized by means of X-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS) mapping, and thermogravimetric analysis (TGA). The results showed that the NiO nanoparticles were surrounded by amorphous carbon. Electrochemical tests demonstrated that the NiO–C nanocomposites exhibited better capacity retention (382 mAh g− 1 for 50 cycles) than that of pure NiO (141 mAh g− 1 for 50 cycles), which was also prepared by spray pyrolysis using …
Rapid Synthesis Of Binary -Nisb-Nis By Microwave Autoclave For Rechargeable Lithium Batteries, Nurul Idris, - Md. Mokhlesur Rahman, Shulei Chou, Jiazhao Wang, David Wexler, Hua Liu
Rapid Synthesis Of Binary -Nisb-Nis By Microwave Autoclave For Rechargeable Lithium Batteries, Nurul Idris, - Md. Mokhlesur Rahman, Shulei Chou, Jiazhao Wang, David Wexler, Hua Liu
Shulei Chou
To reduce the reaction time, electrical energy consumption, and cost, binary α-NiS–β-NiS has been synthesized by a rapid, one-pot, hydrothermal autoclave microwave method within 15 min at temperatures of 160–180 °C. The microstructure and morphology of the α-NiS–β-NiS products were characterized by means of X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and transmission electron microscopy (TEM). At 140 °C, pure hexagonal NiAs-type α-NiS phase was identified from the XRD patterns. With increasing reaction temperature (160–180 °C), the XRD evidence indicates that an increasing fraction of rhombohedral millerite-like β-NiS is formed as a secondary phase. The α-NiS–β-NiS sample synthesized …