Can plasma be formed in catalyst pores? A modeling investigation
Can plasma be formed in catalyst pores? A modeling investigation
复制标题
催化剂孔隙中可以形成等离子体吗？
DOI：
10.1016/j.apcatb.2015.12.009
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发表时间：
2016-05
影响因子：
22.1
通讯作者：
Bogaerts Annemie
中科院分区：
文献类型：
--
作者：
Zhang Yu-Ru;Van Laer Koen;Neyts Erik C.;Bogaerts Annemie
我们用二维流体模型研究了在μm范围内不同孔径和不同外加电压下催化剂孔内微放电的形成。事实上，这在等离子体催化中是一个鲜为人知的现象。计算的对象是大气压下氦气中的介质阻挡放电。为了更好地了解孔内等离子体的特性，我们考察了电子和离子密度、电子温度、电场和电势，以及电子碰撞电离和激发速率以及激发等离子体物种的密度。结果表明，孔径和外加电压是孔内微放电形成的关键参数。当外加电压为20kV时，电离主要发生在孔内，当孔径大于200kVm时，孔附近和孔内的电子密度显著增加，而孔对总离子密度的影响即使在10kVμm孔时也很明显。当孔径固定在30μm时，在2kV的外加电压下，孔的存在对等离子体性质没有显著影响。随着电压的升高，由于较强的电场和较高的电子温度，电离过程增强，在10千伏以上的电压孔附近和孔内离子密度显著增加。这些结果表明，等离子体物种可以在结构化催化剂的孔内(μm范围内)形成，它们可能与催化剂表面相互作用，影响等离子体催化过程。
We investigate microdischarge formation inside catalyst pores by a two-dimensional fluid model for various pore sizes in the μm-range and for various applied voltages. Indeed, this is a poorly understood phenomenon in plasma catalysis. The calculations are performed for a dielectric barrier discharge in helium, at atmospheric pressure. The electron and ion densities, electron temperature, electric field and potential, as well as the electron impact ionization and excitation rate and the densities of excited plasma species, are examined for a better understanding of the characteristics of the plasma inside a pore. The results indicate that the pore size and the applied voltage are critical parameters for the formation of a microdischarge inside a pore. At an applied voltage of 20 kV, our calculations reveal that the ionization mainly takes place inside the pore, and the electron density shows a significant increase near and in the pore for pore sizes larger than 200 μm, whereas the effect of the pore on the total ion density is evident even for 10 μm pores. When the pore size is fixed at 30 μm, the presence of the pore has no significant influence on the plasma properties at an applied voltage of 2 kV. Upon increasing the voltage, the ionization process is enhanced due to the strong electric field and high electron temperature, and the ion density shows a remarkable increase near and in the pore for voltages above 10 kV. These results indicate that the plasma species can be formed inside pores of structured catalysts (in the μm range), and they may interact with the catalyst surface, and affect the plasma catalytic process.
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DOI：
10.1088/0022-3727/44/27/274007
发表时间：
2011-07
期刊：
Journal of Physics D: Applied Physics
影响因子：
--
作者：
X. Tu;H. J. Gallon;Bernard Nisol;Sven Stauss;V. Gibalov;G. Pietsch
通讯作者：
X. Tu;H. J. Gallon;Bernard Nisol;Sven Stauss;V. Gibalov;G. Pietsch
影响因子：
5.3
作者：
Kim, Hyun-Ha;Teramoto, Yoshiyuki;Ogata, Atsushi
通讯作者：
Ogata, Atsushi
影响因子：
22.1
作者：
Subrahmanyam, Ch.;Magureanu, A.;Kiwi-Minsker, L.
通讯作者：
Kiwi-Minsker, L.
影响因子：
22.1
作者：
U. Roland;F. Holzer;F. Kopinke
通讯作者：
U. Roland;F. Holzer;F. Kopinke
影响因子：
5.3
作者：
H. Song;Jae-wook Choi;S. Yue;Hwaung Lee;B. Na
通讯作者：
H. Song;Jae-wook Choi;S. Yue;Hwaung Lee;B. Na