scholarly journals Low-Surface-Area Hard Carbon Anode for Na-Ion Batteries via Graphene Oxide as a Dehydration Agent

2015 ◽  
Vol 7 (4) ◽  
pp. 2626-2631 ◽  
Author(s):  
Wei Luo ◽  
Clement Bommier ◽  
Zelang Jian ◽  
Xin Li ◽  
Rich Carter ◽  
...  
2021 ◽  
Vol 45 (10) ◽  
pp. 4854-4859
Author(s):  
Shao-Fang Li ◽  
Xian-Kun Hou ◽  
Zhen-Yi Gu ◽  
Yun-Feng Meng ◽  
Chen-De Zhao ◽  
...  

Sponge-like NaFe2PO4(SO4)2@reduced graphene oxide composite is prepared as cathode material for sodium-ion batteries. The corresponding full cells matched with hard carbon anode exhibit favorable rate and cyclic performance.


Catalysts ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 256
Author(s):  
Irina V. Pushkareva ◽  
Artem S. Pushkarev ◽  
Valery N. Kalinichenko ◽  
Ratibor G. Chumakov ◽  
Maksim A. Soloviev ◽  
...  

Platinum (Pt)-based electrocatalysts supported by reduced graphene oxide (RGO) were synthesized using two different methods, namely: (i) a conventional two-step polyol process using RGO as the substrate, and (ii) a modified polyol process implicating the simultaneous reduction of a Pt nanoparticle precursor and graphene oxide (GO). The structure, morphology, and electrochemical performances of the obtained Pt/RGO catalysts were studied and compared with a reference Pt/carbon black Vulcan XC-72 (C) sample. It was shown that the Pt/RGO obtained by the optimized simultaneous reduction process had higher Pt utilization and electrochemically active surface area (EASA) values, and a better performance stability. The use of this catalyst at the cathode of a proton exchange membrane fuel cell (PEMFC) led to an increase in its maximum power density of up to 17%, and significantly enhanced its performance especially at high current densities. It is possible to conclude that the optimized synthesis procedure allows for a more uniform distribution of the Pt nanoparticles and ensures better binding of the particles to the surface of the support. The advantages of Pt/RGO synthesized in this way over conventional Pt/C are the high electrical conductivity and specific surface area provided by RGO, as well as a reduction in the percolation limit of the components of the electrocatalytic layer due to the high aspect ratio of RGO.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jeongpil Kim ◽  
Jeong-Hyun Eum ◽  
Junhyeok Kang ◽  
Ohchan Kwon ◽  
Hansung Kim ◽  
...  

AbstractHerein, we introduce a simple method to prepare hierarchical graphene with a tunable pore structure by activating graphene oxide (GO) with a two-step thermal annealing process. First, GO was treated at 600 °C by rapid thermal annealing in air, followed by subsequent thermal annealing in N2. The prepared graphene powder comprised abundant slit nanopores and micropores, showing a large specific surface area of 653.2 m2/g with a microporous surface area of 367.2 m2/g under optimized conditions. The pore structure was easily tunable by controlling the oxidation degree of GO and by the second annealing process. When the graphene powder was used as the supercapacitor electrode, a specific capacitance of 372.1 F/g was achieved at 0.5 A/g in 1 M H2SO4 electrolyte, which is a significantly enhanced value compared to that obtained using activated carbon and commercial reduced GO. The performance of the supercapacitor was highly stable, showing 103.8% retention of specific capacitance after 10,000 cycles at 10 A/g. The influence of pore structure on the supercapacitor performance was systematically investigated by varying the ratio of micro- and external surface areas of graphene.


2020 ◽  
Vol 354 ◽  
pp. 136647 ◽  
Author(s):  
Zoia V. Bobyleva ◽  
Oleg A. Drozhzhin ◽  
Kirill A. Dosaev ◽  
Azusa Kamiyama ◽  
Sergey V. Ryazantsev ◽  
...  

1994 ◽  
Vol 354 ◽  
Author(s):  
K.C. Walter ◽  
H. Kung ◽  
T. Levine ◽  
J.T. Tesmer ◽  
P. Kodali ◽  
...  

AbstractPlasma and ion beam based techniques have been used to deposit carbon-based films. The ion beam based method, a cathodic arc process, used a magnetically mass analyzed beam and is inherently a line-of-sight process. Two hydrocarbon plasma-based, non-line-of-sight techniques were also used and have the advantage of being capable of coating complicated geometries. The self-bias technique can produce hard carbon films, but is dependent on rf power and the surface area of the target. The pulsed-bias technique can also produce hard carbon films but has the additional advantage of being independent of rf power and target surface area. Tribological results indicated the coefficient of friction is nearly the same for carbon films from each deposition process, but the wear rate of the cathodic arc film was five times less than for the self-bias or pulsed-bias films. Although the cathodic arc film was the hardest, contained the highest fraction of sp3 bonds and exhibited the lowest wear rate, the cathodic arc film also produced the highest wear on the 440C stainless steel counterface during tribological testing. Thus, for tribological applications requiring low wear rates for both counterfaces, coating one surface with a very hard, wear resistant film may detrimentally affect the tribological behavior of the counterface.


2021 ◽  
Vol 1044 ◽  
pp. 25-39
Author(s):  
Hafid Khusyaeri ◽  
Dewi Pratiwi ◽  
Haris Ade Kurniawan ◽  
Anisa Raditya Nurohmah ◽  
Cornelius Satria Yudha ◽  
...  

The battery is a storage medium for electrical energy for electronic devices developed effectively and efficiently. Sodium ion battery provide large-scale energy storage systems attributed to the natural existence of the sodium element on earth. The relatively inexpensive production costs and abundant sodium resources in nature make sodium ion batteries attractive to research. Currently, sodium ion batteries electrochemical performance is still less than lithium-ion batteries. The electrochemical performance of a sodium ion battery depends on the type of electrode material used in the manufacture of the batteries.. The main problem is to find a suitable electrode material with a high specific capacity and is stable. It is a struggle to increase the performance of sodium ion batteries. This literature study studied how to prepare high-performance sodium battery anodes through salt doping. The doping method is chosen to increase conductivity and electron transfer. Besides, this method still takes into account the factors of production costs and safety. The abundant coffee waste biomass in Indonesia was chosen as a precursor to preparing a sodium ion battery hard carbon anode to overcome environmental problems and increase the economic value of coffee grounds waste. Utilization of coffee grounds waste as hard carbon is an innovative solution to the accumulation of biomass waste and supports environmentally friendly renewable energy sources in Indonesia.


ChemSusChem ◽  
2019 ◽  
Vol 12 (2) ◽  
pp. 480-486 ◽  
Author(s):  
Dan Thien Nguyen ◽  
Alexander Hoefling ◽  
Minha Yee ◽  
Giang Thi Huong Nguyen ◽  
Patrick Theato ◽  
...  

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