Facile Hydrothermal Synthesis and Supercapacitor Performance of Mesoporous Necklace-Type ZnCo2O4 Nanowires

In this work, mesoporous ZnCo2O4 electrode material with necklace-type nanowires was synthesized by a simple hydrothermal method using water/ethylene glycol mixed solvent and subsequent calcination treatment. The ZnCo2O4 nanowires were assembled by several tiny building blocks of nanoparticles which led to the growth of necklace-type nanowires. The as-synthesized ZnCo2O4 nanowires had porous structures with a high surface area of 25.33 m2 g−1 and with an average mesopore of 23.13 nm. Due to the higher surface area and mesopores, the as-prepared necklace-type ZnCo2O4 nanowires delivered a high specific capacity of 439.6 C g−1 (1099 F g−1) at a current density of 1 A g−1, decent rate performance (47.31% retention at 20 A g−1), and good cyclic stability (84.82 % capacity retention after 5000 cycles). Moreover, a hybrid supercapacitor was fabricated with ZnCo2O4 nanowires as a positive electrode and activated carbon (AC) as a negative electrode (ZnCo2O4 nanowires//AC), which delivered an energy density of 41.87 Wh kg−1 at a power density of 800 W kg−1. The high electrochemical performance and excellent stability of the necklace-type ZnCo2O4 nanowires relate to their unique architecture, high surface area, mesoporous nature, and the synergistic effect between Zn and Co metals.

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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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Synthesis and Characterization of Flower-Like Co–La Oxide Micro/Nano Materials

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1058.25 ◽

2014 ◽

Vol 1058 ◽

pp. 25-29

Author(s):

Shi Jing Lin ◽

Wu Tong Du ◽

Ting Ting Ding ◽

Yu Zhao ◽

You Zhao ◽

...

Keyword(s):

Ethylene Glycol ◽

Surface Area ◽

High Surface ◽

High Surface Area ◽

Building Blocks ◽

Cobalt Nitrate ◽

Element Distribution ◽

Bet Surface Area ◽

Ammonium Bromide ◽

Micrometer Scale

Flower-like Co–La oxide micro/nanomaterials have been synthesized via an ethylene-glycol-mediated process, under the condition of that the mole ratio of lanthanum nitrate (La (NO3)3·6H2O) and cobalt nitrate (Co (NO3)2·6H2O) was 1:1 (based on the amount of Co (NO3)2·6H2O 0.002 mol), the dosage of urea was 2.2 g, the dosage of tetra-butyl ammonium bromide (TBAB) was 6.0 g, with magnetic stirring heating under 170 °C for 60 minutes in the 150mL ethylene glycol, the prepared precursors of Co–La oxides have regular flower-like morphology, in addition, the amount of TBAB and urea plays a significant role on the synthesis of the precursors. The flower-like Co–La oxides micro/nanomaterials were prepared after the precursors were calcinated in the muffle furnace at 800 °C for 2 h, the morphology, crystal properties and element distribution of the products were investigated by the analysis of SEM-EDX, XRD and BET, etc. The structures of these products with regular flower-like morphology are on the micrometer scale, which are hierarchically composed of nanosized building blocks, with highly polycrystalline nature, and the Brunauer–Emmett–Teller (BET) surface area of 68.5 m2/g. Therefore, those micro/nanomaterials have been developed as promising catalytic materials for their not only keeping the high surface area of nanomaterials, but effectively inhibiting aggregation.

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No More HF: Teflon-Assisted Ultrafast Removal of Silica to Generate High-Surface-Area Mesostructured Carbon for Enhanced CO2 Capture and Supercapacitor Performance

Angewandte Chemie ◽

10.1002/ange.201509054 ◽

2016 ◽

Vol 128 (6) ◽

pp. 2072-2076 ◽

Cited By ~ 5

Author(s):

Dheeraj Kumar Singh ◽

Katla Sai Krishna ◽

Srinivasan Harish ◽

Srinivasan Sampath ◽

Muthusamy Eswaramoorthy

Keyword(s):

Surface Area ◽

Co2 Capture ◽

High Surface ◽

High Surface Area ◽

Supercapacitor Performance ◽

Mesostructured Carbon

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Exploring frontiers of crystalline porous materials

Acta Crystallographica Section A Foundations and Advances ◽

10.1107/s205327331408379x ◽

2014 ◽

Vol 70 (a1) ◽

pp. C1620-C1620

Author(s):

Maciej Haranczyk ◽

Richard Martin

Keyword(s):

Porous Materials ◽

Surface Area ◽

Chemical Space ◽

High Surface ◽

3D Structure ◽

High Surface Area ◽

Combinatorial Libraries ◽

Internal Surface ◽

Building Blocks ◽

Geometrical Properties

We present a computational framework for the rapid identification and characterization of high surface area materials from within the vast chemical space of crystalline porous materials such as metal-organic frameworks (MOFs) or covalent organic frameworks (COFs). MOFs and COFs have been the subject of intense research interest due largely to their highly tunable structural properties and record-breaking internal surface areas; gravimetric surface area is one of the most addressed properties of porous materials, and has seen improvement by approximately a factor of twenty since the first reports. However, the design of MOFs with optimum chemical and geometrical properties remains a great challenge, due to the vast combinatorial space of building blocks and topologies in which they can be arranged. Efforts to identify high-performance materials have involved trial-and-error, observation-based design, computational enumeration and screening of large combinatorial libraries as well as optimization-based approaches. In our presentation, we will give an overview of techniques under development in our group, in particular, algorithms for 3D structure model assembly and material characterization. We will also present how these tools can be employed in both enumeration and optimization-based discovery of novel materials.

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Hierarchical nanosheet-based NiMoO4 nanotubes: synthesis and high supercapacitor performance

Journal of Materials Chemistry A ◽

10.1039/c4ta05468g ◽

2015 ◽

Vol 3 (2) ◽

pp. 739-745 ◽

Cited By ~ 114

Author(s):

Zhuoxun Yin ◽

Shen Zhang ◽

Yujin Chen ◽

Peng Gao ◽

Chunling Zhu ◽

...

Keyword(s):

Surface Area ◽

Hydrothermal Treatment ◽

High Surface ◽

High Surface Area ◽

Diffusion Reaction ◽

Electrochemical Performances ◽

Reaction Method ◽

Ultrathin Nanosheets ◽

Supercapacitor Performance

Hierarchical nanosheet-based NiMoO4 nanotubes with a high surface area of 128.5 m2 g−1, composed of highly ordered ultrathin nanosheets with a thickness of less than 10 nm, were synthesized by a hydrothermal treatment and a subsequent in situ diffusion reaction method, exhibiting excellent electrochemical performances.

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Synthesis of Dense Mesoporous Silica with High Surface Area by Hydrothermal Hot-Pressing (HHP) Method

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.124-126.1833 ◽

2007 ◽

Vol 124-126 ◽

pp. 1833-1836 ◽

Cited By ~ 1

Author(s):

Mari Takimura ◽

Hidezumi Nagata ◽

Yuki Yamasaki ◽

Atsushi Nakahira

Keyword(s):

Mesoporous Silica ◽

Specific Surface ◽

Surface Area ◽

Hot Pressing ◽

High Surface ◽

High Surface Area ◽

Surface Areas ◽

Mesopore Structure ◽

Subsequent Calcination ◽

Specific Surface Areas

In this study, the synthesis of the bulky and dense mesoporous silica such as FSM was attempted by a hydrothermal hot-pressing (HHP) with a surfactant as a template and a subsequent calcination. According to TEM observation, the dense bulks obtained by HHP had a hexagonal mesopore structure. Also, these dense FSM bulks possessed high specific surface areas. Furthermore, Ag-supported dense FSM bulks were successfully synthesized by HHP with Ag salt and a subsequent calcination in H2. Thus, this HHP method is useful for synthesizing dense bulks and simultaneous supporting novel metals such as Ag on bulky FSM.

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Solution-processed poly(3,4-ethylenedioxythiophene) nanocomposite paper electrodes for high-capacitance flexible supercapacitors

Journal of Materials Chemistry A ◽

10.1039/c5ta10122k ◽

2016 ◽

Vol 4 (5) ◽

pp. 1714-1722 ◽

Cited By ~ 65

Author(s):

Zhaohui Wang ◽

Petter Tammela ◽

Jinxing Huo ◽

Peng Zhang ◽

Maria Strømme ◽

...

Keyword(s):

Surface Area ◽

Sheet Resistance ◽

High Surface ◽

High Surface Area ◽

Building Blocks ◽

Solution Processed ◽

Chemical Polymerization ◽

High Capacitance ◽

Capacitive Performance ◽

Flexible Supercapacitors

Nanostructured flexible PEDOT paper can be constructed by straightforward chemical polymerization on nanocellulose building blocks, yielding a high surface area, low sheet resistance and outstanding capacitive performance.

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Temperature dependence for high electrical performance of Mn-doped high surface area activated carbon (HSAC) as additives for hybrid capacitor

Scientific Reports ◽

10.1038/s41598-020-79469-7 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Zambaga Otgonbayar ◽

Kamrun Nahar Fatema ◽

Sunhye Yang ◽

Ick-Jun Kim ◽

Minchul Kim ◽

...

Keyword(s):

Activated Carbon ◽

Surface Area ◽

High Efficiency ◽

High Surface ◽

Specific Capacity ◽

High Surface Area ◽

Carbon Composite ◽

Electrical Performance ◽

Pore Size Distributions ◽

Mn Doped

AbstractHerein, we manufactured the positive and negative electrodes for the hybrid capacitor. The Mn-doped High surface area of Activated carbon composite used for the positive electrode and as-prepared composite was calcined at 600 °C and 800 °C. The morphological structures and pore-size distributions of MnYP-600HTT and MnYP-800HTT were characterized by means of XRD, SEM, EDAX, TEM, and BET. According to the BET specific surface-area evaluation, MnYP-600HTT and MnYP-800HTT were 1272.6 and 1388.1 m2/g, respectively. Total pore volumes were 0.627 and 0.687 cm3/g, which is beneficial for forming ion-transport channels in electrochemical reactions. The MnYP-600HTT electrode had a high specific capacity of 177.2 mAh/g at 20C, and the capacity retention was 64.8%. During the entire cycling, MnYP-600HTT had excellent cyclic stability in 500 cycles along with high efficiency. The robust design of the MnYP-600HTT and MnYP-800HTT cathode materials introduced in this work pave the way for designing next-generation supercapacitors operating at ultra-high C rates. The Mn-doped high surface of activated carbon had stable energy density and superior cycling stability that were demonstrated in supercapacitor systems.

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