As far as I know, there is no investigation about the role of the dielectric material on the a DBD. The role of the dielectric is to avoid charge exchange with the covered electrode(s). We are investigating discharge to favor the dissociation of CO2 through vibrational excitation. The model is quite complex and still with large uncertainties. 

We have investigated the effect of vibrational excitation in hydrogen DBD, showing that non equilibrium vibration increase dissociation reducing ionization. We can suppose that a similar effect can be obtained in CO2. but it must be proved yes.

Development of gas cleaning technology for efficient power plant will contribute for reduction in emission of greenhouse gases. Therefore, non-thermal plasma technology, presently still in laboratory experimental stage., can potentially be applied for various gas-phase chemical reactions. My works and our experiences in the field of low-temperature plasma (electrical corona discharges) could be useful for your interests in cleaning environmental.

It seems to me that the gas chosen for the DBD would have a more significant impact than the dielectric chosen.  The gases present and the applied voltages would impact whether or not you form things like CO2 or ozone.

Gases, OK, however, which effective dielectric materials may be used between the discharge electrodes to be removed the emission of these greenhouse gases?

 Hi Reda,

When you choose a dielectric there are 2 main things you should consider:

1) Dielectric strength - The voltage at which the mateiral breaks down and transition to an arc occurs

2) Dielectric constant - the relative polarisability of the material

For good dielectric strength dense sintered ceramics, ruby mica, and quartz glass are seemingly effective. My preference would be quartz glass, although others use alumina as it is more durable. I don't like alumina as I have found the breakdown strength to be lower than with quartz, although this is also dependent on barrier thickness. Unfortunately, the dielectric strength specifications provide by manufacturers often do not apply when the materials are subjected to the DBD environment. I believe this is due to heating of the dielectric, migration of ions in the dielectric (this only applies to ceramics) when subjected to high frequency electric fields, and electron-ion sputtering of the dielectric. This problem is worst with ceramics.

For the dielectric constant, this modifies the breakdown voltage of the gas by magnifying local electric field strengths in the gas gap. High dielectric constant materials (such as BaTiO3) have a greater magnifying effect of the electric field. This causes electrical breakdown to occur at lower applied voltages. I think, although I am not certain, that this results in a higher than normal average electron energy. It might also mean fewer microdischarges, although I am not sure. In CO2 containing plasmas, this will mean more electron impact dissociation, caused by the higher energy electrons. Although, I think there may be a trade off between the number of microdischarges formed. Alp Ozkan has recent published a paper on dielectric effect on CO2 conversion, I haven't read it in detail but I believe it is a good paper. https://www.researchgate.net/publication/304627748_How_do_the_barrier_thickness_and_dielectric_material_influence_the_filamentary_mode_and_CO2_conversion_in_a_flowing_DBD

Also worth noting that vibrational excitation is not believed to lead to a high level of CO2 dissociation in DBD (See papers by Aerts and Bogaerts on CO2 dissociation modelling). I also suggest reading Brehmer at al for a good general overview of CO2 conversion in DBD. (https://doi.org/10.1063/1.4896132), 

I hope this helps.

Article How do the barrier thickness and dielectric material influen...

Hi Reda,

As i know, in dielectric barrier discharges, the dielectric material reduces the voltage and prevents from arc. Another main duty of dielectric is to production of secondary electron emission due to ions impact. It is evident to me that the reactions between gases or between particles in plasma is responsible to production or distraction of different particles and radiations. I have investigated the main radiation in Ar/Cl discharges and i saw that the radiations such as ArCl* is just produced or distract due to  impact of Ar and Cl ions. 

I hope this help you

Hi Reda

actually Im working on the project for six months ago , as far as my invetegates  one must reach an electron energy of glow discharge stable and well distributed via your design the electron energy you should reach for co2 dissociation around 11ev. this temperature cant be reached unless you should find a dielectric material having dielectric strength with stands 100kv per mm (if the space between the electrodes with the bariar in mm range). so I think you should try alumina thermal treated with glass coating  of 1mm thick and applying 110 kv for the dischaging to reach 11ev temperature of electron.

Hi Kamal

THANKS for your great interest. I would like to say that among the advantages of DBD, they do not need complicated power source and they are easy to build up. So, applying 110kV for the discharging somewhat is difficult. 

Dear Reda

110kv is for total co2 dissocoation to its basic atmos c+o+o 

But if you want just to reach to co+o the voltage you will need is only 3kv. This is for a scintific reason . If you want me to give you details im ready. But I think you can conclurd the reason why we need such energy for co dissociation isnt it?

Dear Kamal

Many THANKS for your greet interest. I hope contacts between us in future about the related interests.

Best Wishes

Ok. Not at all

Best wishes