Mn3 O4 @C Nanoparticles Supported on Porous Carbon as Bifunctional Oxygen Electrodes and their Electrocatalytic Mechanism

2018 ◽  
Vol 6 (2) ◽  
pp. 359-368 ◽  
Author(s):  
Ms. Wanqing Li ◽  
Mr. Hongquan Fu ◽  
Yonghai Cao ◽  
Hongjuan Wang ◽  
Hao Yu ◽  
...  
Keyword(s):  
Porous Carbon ◽  
Electrocatalytic Mechanism ◽  
Oxygen Electrodes

scholarly journals Nanowrinkled Carbon Aerogels Embedded with FeNx Sites as Effective Oxygen Electrodes for Rechargeable Zinc-Air Battery

Research ◽  
2019 ◽  
Vol 2019 ◽  
pp. 1-13 ◽  
Author(s):  
Ting He ◽  
Bingzhang Lu ◽  
Yang Chen ◽  
Yong Wang ◽  
Yaqiang Zhang ◽  
...  
Keyword(s):  
Porous Carbon ◽  
High Performance ◽  
Rational Design ◽  
Single Atom ◽  
Carbon Aerogels ◽  
Highly Active ◽  
Structural Distortions ◽  
Oxygen Electrodes ◽  
A Minor ◽  
X Ray Absorption

Rational design of single-metal atom sites in carbon substrates by a flexible strategy is highly desired for the preparation of high-performance catalysts for metal-air batteries. In this study, biomass hydrogel reactors are utilized as structural templates to prepare carbon aerogels embedded with single iron atoms by controlled pyrolysis. The tortuous and interlaced hydrogel chains lead to the formation of abundant nanowrinkles in the porous carbon aerogels, and single iron atoms are dispersed and stabilized within the defective carbon skeletons. X-ray absorption spectroscopy measurements indicate that the iron centers are mostly involved in the coordination structure of FeN4, with a minor fraction (ca. 1/5) in the form of FeN3C. First-principles calculations show that the FeNx sites in the Stone-Wales configurations induced by the nanowrinkles of the hierarchically porous carbon aerogels show a much lower free energy than the normal counterparts. The resulting iron and nitrogen-codoped carbon aerogels exhibit excellent and reversible oxygen electrocatalytic activity, and can be used as bifunctional cathode catalysts in rechargeable Zn-air batteries, with a performance even better than that based on commercial Pt/C and RuO2 catalysts. Results from this study highlight the significance of structural distortions of the metal sites in carbon matrices in the design and engineering of highly active single-atom catalysts.

Ultrathin Carbon Nanosheets for Highly-efficient Capacitive K-ion and Zn-ion Storage

2020 ◽  
Author(s):  
Yamin Zhang ◽  
Zhongpu Wang ◽  
Deping Li ◽  
Qing Sun ◽  
Kangrong Lai ◽  
...  
Keyword(s):  
Energy Storage ◽  
Porous Carbon ◽  
Metal Ion ◽  
Rate Capability ◽  
Energy Storage Devices ◽  
Capacity Retention ◽  
Carbon Nanosheets ◽  
Storage Devices ◽  
High Efficient ◽  
Ion Storage

<p></p><p>Porous carbon has attracted extensive attentions as the electrode material for various energy storage devices considering its advantages like high theoretical capacitance/capacity, high conductivity, low cost and earth abundant inherence. However, there still exists some disadvantages limiting its further applications, such as the tedious fabrication process, limited metal-ion transport kinetics and undesired structure deformation at harsh electrochemical conditions. Herein, we report a facile strategy, with calcium gluconate firstly reported as the carbon source, to fabricate ultrathin porous carbon nanosheets. <a>The as-prepared Ca-900 electrode delivers excellent K-ion storage performance including high reversible capacity (430.7 mAh g<sup>-1</sup>), superior rate capability (154.8 mAh g<sup>-1</sup> at an ultrahigh current density of 5.0 A g<sup>-1</sup>) and ultra-stable long-term cycling stability (a high capacity retention ratio of ~81.2% after 4000 cycles at 1.0 A g<sup>-1</sup>). </a>Similarly, when being applied in Zn-ion capacitors, the Ca-900 electrode also exhibits an ultra-stable cycling performance with ~90.9% capacity retention after 4000 cycles at 1.0 A g<sup>-1</sup>, illuminating the applicable potentials. Moreover, the origin of the fast and smooth metal-ion storage is also revealed by carefully designed consecutive CV measurements. Overall, considering the facile preparation strategy, unique structure, application flexibility and in-depth mechanism investigations, this work will deepen the fundamental understandings and boost the commercialization of high-efficient energy storage devices like potassium-ion/sodium-ion batteries, zinc-ion batteries/capacitors and aluminum-ion batteries.</p><br><p></p>

Radar Absorbing Properties of Light Radar Absorbing Materials Based on Hollow-porous Carbon Fibers

2009 ◽  
Vol 24 (2) ◽  
pp. 320-324 ◽  
Author(s):  
Wei XIE ◽  
Hai-Feng CHENG ◽  
Zeng-Yong CHU ◽  
Zhao-Hui CHEN ◽  
Yong-Jiang ZHOU
Keyword(s):  
Carbon Fibers ◽  
Porous Carbon ◽  
Absorbing Materials

CO2 Capture & Separation in Microporous Materials: A Comparison Between Porous Carbon and Flexible MOFs

2018 ◽  
Vol 28 (7) ◽  
pp. 417-422
Author(s):  
Minji Jung ◽  
Seoha Park ◽  
Hyunchul Oh ◽  
Kwi-il Park
Keyword(s):  
Porous Carbon ◽  
Microporous Materials

An experimental dynamic method of investigation of counter-current absorption of oxygen in water in a packed bed column

1987 ◽  
Vol 52 (7) ◽  
pp. 1715-1729 ◽  
Author(s):  
Pavel Moravec ◽  
Vladimír Staněk
Keyword(s):  
Transfer Functions ◽  
Simultaneous Detection ◽  
Harmonic Component ◽  
Packed Bed ◽  
Packed Bed Column ◽  
Oxygen Electrodes ◽  
Simultaneous Evaluation ◽  
Physical Absorption ◽  
On Line ◽  
Counter Current

An experimental method and technique are described in the paper of simultaneous detection of the transfer functions outlet-gas-stream-to-inlet-gas-stream and outlet-liquid-stream-to-inlet-gas-stream for the absorption of oxygen into water in a counter-current packed bed column. Both transfer functions were simultaneously monitored by means of three oxygen electrodes operating on the polarographic principle. The signals of these electrodes were processed in three steps to yield parameters of the model of physical absorption of gas. The first step was on-line evaluation of the Fourier coefficients of the principal harmonic component in all three monitored streams. The second step was the calculation of the frequency characteristics of both transfer functions while the third step yielded parameters of the model by optimization in the frequency domain. The method permits simultaneous evaluation of the parameters of the flow of both phases in the column and the interfacial transfer of oxygen.

Single Mn atom anchored on N-doped porous carbon as highly efficient Fenton-like catalyst for the degradation of organic contaminants

2020 ◽  
Vol 279 ◽  
pp. 119363 ◽  
Author(s):  
Jingren Yang ◽  
Deqian Zeng ◽  
Qinggang Zhang ◽  
Ruofan Cui ◽  
Muhammad Hassan ◽  
...  
Keyword(s):  
Porous Carbon ◽  
Organic Contaminants ◽  
Highly Efficient
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