The Stable 3D Zn Electrode for High-Power Density Zn Metal Batteries

Abstract A stable Zn metal electrode can develop rechargeable zinc metal batteries (RZMBs) which have the high theoretical capacity (820 mAh/g), low redox potential, and intrinsic safety. However, the corrosion of Zn metal in aqueous electrolytes and Zn dendrite formation during the plating process leads to poor cycling and thus hinders the development of RZMBs. Here, we employed ionic liquid-based gel polymer (poly(vinylidene fluoride)-co-hexafluoropropylene, PVDF-HFP) and acetylene black (AB) to achieve a stable and flexible three-dimensional (3D) Zn/AB/PVDF-HFP film electrode with ionic and electronic conductive networks and high surface area, showing 26 times higher plating/stripping current than planar Zn plate. By developing a continuous structure between the ionic liquid-based gel polymer membrane and the flexible 3D Zn/AB/PVDF-HFP electrode, the low resistance, high rate capability and long cycle life (> 800 h) was obtained. Our work shows a flexible Zn film electrode and ionic liquid-based gel polymer electrolyte, could pave the path for rechargeable and high-cycle life thin-film RZMBs.

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Synthesis of Hierarchical Graphene-MnO2 Nanowire Composites with Enhanced Specific Capacitance

Asian Journal of Chemistry ◽

10.14233/ajchem.2019.21924 ◽

2019 ◽

Vol 31 (8) ◽

pp. 1709-1718

Author(s):

T. Veldevi ◽

K. Thileep Kumar ◽

R.A. Kalaivani ◽

S. Raghu ◽

A.M. Shanmugharaj

Keyword(s):

Surface Area ◽

Electrode Materials ◽

High Surface ◽

Specific Capacity ◽

High Surface Area ◽

Rate Capability ◽

Sulfate Solution ◽

High Rate ◽

Chemical Compositions ◽

Structure Morphology

Hierarchical nanostructured graphene–manganese dioxide nanowire (G-MnO2-NW) composites have been prepared by hydrothermal synthesis route using water/1-decanol as the medium. Synthesized materials were analyzed using various characterization tools to corroborate their chemical compositions, structure/morphology and surface area. Electrochemical measurements of the synthesized G-MnO2-NW electrode materials delivered the highest specific capacity (255 Fg-1), high rate capability and improved cycling stability at 0.5 Ag–1 in 1M sodium sulfate solution and this fact may be attributed to its high surface area and porosity. Moreover, synthesized G-MnO2-NW electrodes displayed better energy and power density, when compared to the MnO2-NW based electrodes.

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Tailoring of Aqueous-Based Carbon Nanotube–Nanocellulose Films as Self-Standing Flexible Anodes for Lithium-Ion Storage

Nanomaterials ◽

10.3390/nano9040655 ◽

2019 ◽

Vol 9 (4) ◽

pp. 655 ◽

Cited By ~ 6

Author(s):

Hoang Kha Nguyen ◽

Jaehan Bae ◽

Jaehyun Hur ◽

Sang Joon Park ◽

Min Sang Park ◽

...

Keyword(s):

Carbon Nanotube ◽

High Surface ◽

High Surface Area ◽

Composite Films ◽

Rate Capability ◽

Morphological Characteristics ◽

Lithium Ion ◽

Reversible Capacity ◽

High Rate ◽

Voltage Profile

An easy and environmentally friendly method was developed for the preparation of a stabilized carbon nanotube–crystalline nanocellulose (CNT–CNC) dispersion and for its deposition to generate self-standing CNT–CNC composite films. The composite films were carbonized at different temperatures of 70 °C, 800 °C, and 1300 °C. Structural and morphological characteristics of the CNT–CNC films were investigated by X-ray diffraction (XRD), Raman spectroscopy, and scanning electron microscopy (SEM), which revealed that the sample annealed at 800 °C (CNT–CNC800) formed nano-tree networks of CNTs with a high surface area (1180 m2·g−1) and generated a conductive CNC matrix due to the effective carbonization. The carbonized composite films were applied as anodes for lithium-ion batteries, and the battery performance was evaluated in terms of initial voltage profile, cyclic voltammetry, capacity, cycling stability, and current rate efficiency. Among them, the CNT–CNC800 anode exhibited impressive electrochemical performance by showing a reversible capacity of 443 mAh·g−1 at a current density of 232 mA·g−1 after 120 cycles with the capacity retention of 89% and high rate capability.

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Jackfruit Seed-Derived Nanoporous Carbons as the Electrode Material for Supercapacitors

C – Journal of Carbon Research ◽

10.3390/c6040073 ◽

2020 ◽

Vol 6 (4) ◽

pp. 73 ◽

Cited By ~ 1

Author(s):

Rashma Chaudhary ◽

Subrata Maji ◽

Rekha Goswami Shrestha ◽

Ram Lal Shrestha ◽

Timila Shrestha ◽

...

Keyword(s):

Carbon Materials ◽

Activated Carbons ◽

High Current Density ◽

Chemical Activation ◽

High Surface ◽

High Surface Area ◽

Rate Capability ◽

High Specific Capacitance ◽

High Rate ◽

Nanoporous Carbons

Hierarchically porous activated carbon materials from agro-waste, Jackfruit seeds are prepared by a chemical activation method involving the treatment with zinc chloride (ZnCl2) at different temperatures (600–1000 °C). The electrochemical supercapacitance performances of the prepared materials were studied in an aqueous electrolyte (1 M sulfuric acid, H2SO4) in a three-electrode system. Jackfruit seed carbons display nanoporous structures consisting of both micro- and mesopore architectures and they are amorphous in nature and also contain oxygenated surface functional groups, as confirmed by powder X-ray diffraction (pXRD), Raman scattering, and Fourier-transformed infrared (FTIR) spectroscopy, respectively. The surface areas and pore volumes were found to be 1216.0 to 1340.4 m2·g−1 and 0.804 to 1.144 cm3·g−1, respectively, demonstrating the better surface textural properties compared to the commercial activated carbons. Due to the high surface area, large pore volume, and well developed hierarchical micro- and mesoporosity, the optimal sample achieved a high specific capacitance of 292.2 F·g−1 at 5 mV·s−1 and 261.3 F·g−1 at 1 A·g−1 followed by outstanding high rate capability. The electrode sustained 71.6% capacity retention at a high current density of 20 A·g−1. Furthermore, the electrode displayed exceptional cycling stability with small capacitance loss (0.6%) even after 10,000 charging–discharging cycles, suggesting that Jackfruit seed would have potential in low-cost and scalable production of nanoporous carbon materials for supercapacitors applications.

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Efficiency Enhancement in Dye-Sensitized Solar Cell Using TiO2 /Ilmenite-Derived Nanofiber Composite as Working Electrode

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.925.600 ◽

2014 ◽

Vol 925 ◽

pp. 600-604

Author(s):

Athapon Simpraditpan ◽

Thanakorn Wirunmongkol ◽

Sorapong Pavasupree ◽

Wisanu Pecharapa

Keyword(s):

Nanocomposite Film ◽

High Surface ◽

Hydrothermal Process ◽

High Surface Area ◽

Dye Sensitized Solar Cells ◽

Nanocomposite Films ◽

Film Electrode ◽

Photoelectric Conversion ◽

Dye Sensitized ◽

Working Electrode

TiO2 nanocomposite films of calcined TiO2 nanofibers and commercial-grade TiO2 nanoparticles Degussa (P25) utilized as working electrode of dye-sensitized solar cells (DSSCs) are prepared by a doctor blade method. TiO2 nanofibers were synthesized from ilmenite mineral by hydrothermal process in combination with calcinations process. The prepared samples are characterized by XRD, XPS and TEM. The photoelectric conversion performance of the DSSC based on nanocomposite film electrode was compared to the device fabricated by pure P25 at the same film thickness. The result shows that as calcination temperature increases, the transformation of nanofibers to nanorods and nanoparticles were observed. The energy conversion efficiency (ƞ) of the device tends to with increasing calcined temperature. The greatest ƞ is 3.90% obtained from DSSC fabricated from nanocomposite film electrode of 5 wt.% nanofibers calcined at 800 oC for 2 h mixed with P25, indicating the significant enhancement in its performance by the incorporation of the nanofibers. This enhancement of DSSCs may correlate to high surface area, higher light scattering and light harvesting, low charge recombination and fast electron-transfer rate by nanofibers.

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Efficient and Reusable Silica Gel Supported Metal Ionic Liquid Catalysts for Palmitic Acid Esterification to Biodiesel

Journal of the chemical society of pakistan ◽

10.52568/000014 ◽

2021 ◽

Vol 43 (1) ◽

pp. 1-1

Author(s):

Guo Yingwei Guo Yingwei ◽

Chen Xuedan Chen Xuedan ◽

Yan Shiting Yan Shiting ◽

Zhang Zhengliang Zhang Zhengliang ◽

Chen Yuqin Chen Yuqin ◽

...

Keyword(s):

Ionic Liquid ◽

Palmitic Acid ◽

Silica Gel ◽

High Surface ◽

High Surface Area ◽

Kinetic Studies ◽

Catalytic Performance ◽

Reaction Conditions ◽

Acid Esterification ◽

Supported Metal

A series of silica gel (SG) supported metal ionic liquid catalysts (x[Bmim]Cl-CrCl3/SG) were synthesized and exploited for the esterification of palmitic acid (PA) with methanol (ML) to produce biodiesel efficiently. The 10%[Bmim]Cl-CrCl3/SG catalyst with high surface area and desirable acidity exhibited the best catalytic performance and reusability after six consecutive running cycles. Based on the response surface analysis, the optimal reaction conditions were obtained as follows: methanol/acid mole ratio = 11:1 mol/mol, catalyst amount = 5.3 wt%, reaction time = 65 min, as well as reaction temperature = 373 K, reaching to a biodiesel yield of 96.1%. Further kinetic studies demonstrated that the esterification of PA with ML obeyed 1.41 order kinetics for acid concentration with the activation energy of 16.88 kJ/mol

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