Enhancing the efficiency of direct carbon fuel cells by bubbling Ar gas in carbon/carbonate slurry
Enhancing the efficiency of direct carbon fuel cells by bubbling Ar gas in carbon/carbonate slurry
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DOI：
10.1016/j.jpowsour.2014.09.079
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发表时间：
2015
影响因子：
9.2
通讯作者：
Hirotatsu Watanabe;T. Furuyama;K. Okazaki
中科院分区：
文献类型：
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作者：
Hirotatsu Watanabe;T. Furuyama;K. Okazaki
本研究旨在通过在碳/碳酸盐浆中鼓泡氩气来提高直接碳燃料电池（DCFC）的效率。测量了在20ma cm−2放电时的电流放电曲线和CO和co2产率。当碳酸盐中碳含量（WC/碳酸盐）为1.0 wt%时，Ar鼓泡使CO/ co2产率从0.16降低到0.051，提高了co2产率，接近于碳完全电化学氧化的理论值。在稳态下，鼓泡使电池电压提高了约0.1 V。当wc /碳酸盐= 3.0 wt%时，无鼓泡的CO/ co2产率显著提高至8.5，表明部分电化学氧化成为主导。C/O2−比值是解释碳的电化学氧化的关键。当C/O2−比较低时，如atWC/碳酸盐= 1.0 wt%，完全电化学氧化成为主导，鼓泡强化了完全电化学氧化。当C/O2−比较高时，如atWC/碳酸盐= 3.0 wt%，部分电化学氧化成为主导，鼓泡对其没有抑制作用。当wc /碳酸盐浓度为1.0 wt%时，鼓泡提高了库仑效率和电压效率，使总效率从52%提高到64%。
This study aims to enhance the direct carbon fuel cell (DCFC) efficiency by bubbling Ar gas in a carbon/carbonate slurry. The current discharge curve and CO and CO2production rates were measured during discharge at 20 mA cm−2. When carbon content in carbonates (WC/carbonate) was 1.0 wt%, Ar bubbling decreased the CO/CO2production ratio from 0.16 to 0.051, and increased the CO2production rate, which approached the theoretical value for complete electrochemical oxidation of carbon. Moreover, bubbling increased the cell voltage by about 0.1 V at steady state. AtWC/carbonate= 3.0 wt%, the CO/CO2production ratio without bubbling increased significantly to 8.5, indicating that partial electrochemical oxidation became dominant. The C/O2−ratio is key for explaining the electrochemical oxidation of the carbon. When the C/O2−ratio was low, such as atWC/carbonate= 1.0 wt%, complete electrochemical oxidation became dominant, and bubbling enhanced the complete electrochemical oxidation. When the C/O2−ratio was high, such as atWC/carbonate= 3.0 wt%, partial electrochemical oxidation became dominant, and bubbling did not inhibit it. ForWC/carbonate= 1.0 wt%, bubbling increased both coulombic and voltage efficiencies, resulting in an increase in total efficiency from 52% to 64%.