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991.
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Hu Xingjun Liu Yu Yan Wei Zhang Jinglong Wang Jingyu Lan Wei Sang Tao Yu Tianming 《Journal of Mechanical Science and Technology》2021,35(5):2035-2047
Journal of Mechanical Science and Technology - To optimize the overall heat dissipation performance of the straight channel of a cold plate for lithium battery in vehicles, we used the wavy channel... 相似文献
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995.
Xue Mi Bo Gao Xiaoyue Tan Minhui Xie Chunjuan Gao Yu Liu Jianping Gao 《International Journal of Hydrogen Energy》2021,46(7):5332-5344
In this paper, iron and nitrogen co-doped carbon material with nanotube structure (Fe/N-CCM-T) was synthesized by pyrolyzing a mixture of Fe salt, chitosan and melamine and displayed high electrocatalytic performance for oxygen reduction reaction (ORR). The structure of the Fe/N-CCM-T was characterized and their ORR performance in alkaline media was investigated by linear sweep voltammetry, cyclic voltammetry and chronoamperometry. Fe/N-CCM-T displayed better ORR performance than other carbon materials like Fe/N-CC-800. The Fe/N-CCM-800 with a large surface area (302.5 m2/g) especially exhibited the best ORR electrocatalytic performance among the prepared carbon materials, which was also proved by its similar Tafel slope (76 mV decade?1) to Pt/C catalyst (74 mV decade?1). Fe/N-CCM-800 showed similar ORR activity as commercial Pt/C catalyst, but superior tolerance to methanol and stability. Such high ORR performance of the Fe/N-CCM-T can be attributed to its nanotube structure, high specific surface area (SSA), high graphitic-N and pyridinic-N contents. 相似文献
996.
Xi Chen Zhengkun Yu Chen Yang Yao Chen Chao Jin Yuejiao Ding Wenbin Li Zhongmin Wan 《International Journal of Hydrogen Energy》2021,46(19):11127-11139
Flow field structure can largely determine the output performance of Polymer electrolyte membrane fuel cell. Excellent channel configuration accelerates electrochemical reactions in the catalytic layer, effectively avoiding flooding on the cathode side. In present study, a three-dimensional, multi-phase model of PEMFC with a 3D wave flow channel is established. CFD method is applied to optimize the geometry constructions of three-dimensional wave flow channels. The results reveal that 3D wave flow channel is overall better than straight channel in promoting reactant gases transport, removing liquid water accumulated in microporous layer and avoiding thermal stress concentration in the membrane. Moreover, results show the optimal flow channel minimum depth and wave length of the 3D wave flow channel are 0.45 mm and 2 mm, respectively. Due to the periodic geometric characteristics of the wave channel, the convective mass transfer is introduced, improving gas flow rate in through-plane direction. Furthermore, when the cell output voltage is 0.4 V, the current density in the novel channel is 23.8% higher than that of conventional channel. 相似文献
997.
E.A. Filonova E.Yu. Pikalova T.Yu. Maksimchuk A.I. Vylkov S.M. Pikalov A. Maignan 《International Journal of Hydrogen Energy》2021,46(32):17037-17050
Complex oxides Nd1.6Ca0.4Ni1-yCuyO4+δ (y = 0.0–0.4) have been prepared by a pyrolysis of glycerol-nitrate compositions. According to the X-ray diffraction analysis, the materials are single-phase up to y = 0.3 and crystallize in an orthorhombic structure (Bmab) at room temperature. High-temperature studies assert that they all undergo a phase transition from orthorhombic to tetragonal (I4/mmm) structure in a range of 300–400 °C. With Cu doping, the over-stoichiometric oxygen content δ decreases from 0.07 (y = 0.0) down to 0.00 (y = 0.3). The studies on the compact samples reveal the maximum value of total conductivity (165 S cm?1 at 420 °C) and the minimum value of the linear coefficient of thermal expansion (11.9·10?6 K?1 in a range of 400–1000 °C in air) at y = 0.2. Chemical compatibility of the Nd1.6Cа0.4Ni1-yCuyO4+δ (y = 0.0, 0.2) oxides with oxygen- and proton conducting electrolytes (Ce0.9Gd0.1O1.95, Ce0.8Sm0.2O1.9 and BaCe0.5Zr0.3Y0.1Yb0.1O3-δ) up to a temperature of 1100 °C is demonstrated. 相似文献
998.
Hang Shi Qiuyang Yu Guoliang Liu Xiaohong Hu 《International Journal of Hydrogen Energy》2021,46(33):17097-17105
Transition metal phosphides (TMPs) have been considered as cheap alternatives of precious metal platinum for electrochemical hydrogen evolution reaction (HER). In the past decades, many reports have indicated that the engineering of heterointerfaces between different components could efficiently enhance the activity of HER catalysts. Here, we report a facile method to construct Ni12P5–Ni2P heterostructure by using a low temperature phosphorization strategy. The obtained Ni12P5–Ni2P heterostructure shows high activity toward HER with an overpotential value of 166 mV at 10 mA cm?2 and a Tafel slope of 60 mV dec?1 in 0.5 M H2SO4. Compared with pure Ni2P and Ni12P5, the Ni12P5–Ni2P heterostructure has more active sites and faster HER kinetics due to the presence of the interfaces between Ni12P5 and Ni2P. Furthermore, we used the obtained Ni12P5–Ni2P as cathodic catalyst and IrO2/Ti as anodic material to set up a proton exchange membrane (PEM) electrolyzer which shows good stability after 120 h continuous constant current electrolysis at 200 mA cm?2. This work demonstrates the positive effect of heterostructure for HER catalysts and provides a feasible strategy for constructing earth-abundant electrocatalysts. 相似文献
999.
Minli Yu Ke Wang Harrie Vredenburg 《International Journal of Hydrogen Energy》2021,46(41):21261-21273
The primary aim of this study is to provide insights into different low-carbon hydrogen production methods. Low-carbon hydrogen includes green hydrogen (hydrogen from renewable electricity), blue hydrogen (hydrogen from fossil fuels with CO2 emissions reduced by the use of Carbon Capture Use and Storage) and aqua hydrogen (hydrogen from fossil fuels via the new technology). Green hydrogen is an expensive strategy compared to fossil-based hydrogen. Blue hydrogen has some attractive features, but the CCUS technology is high cost and blue hydrogen is not inherently carbon free. Therefore, engineering scientists have been focusing on developing other low-cost and low-carbon hydrogen technology. A new economical technology to extract hydrogen from oil sands (natural bitumen) and oil fields with very low cost and without carbon emissions has been developed and commercialized in Western Canada. Aqua hydrogen is a term we have coined for production of hydrogen from this new hydrogen production technology. Aqua is a color halfway between green and blue and thus represents a form of hydrogen production that does not emit CO2, like green hydrogen, yet is produced from fossil fuel energy, like blue hydrogen. Unlike CCUS, blue hydrogen, which is clearly compensatory with respect to carbon emissions as it captures, uses and stores produced CO2, the new production method is transformative in that it does not emit CO2 in the first place. In order to promote the development of the low-carbon hydrogen economy, the current challenges, future directions and policy recommendations of low-carbon hydrogen production methods including green hydrogen, blue hydrogen, and aqua hydrogen are investigated in the paper. 相似文献
1000.