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The increasing anthropogenic emission of greenhouse gases (GHGs) is causing global warming which is a matter of deep public concern. Dry reforming of methane (DRM) is an attractive means of reducing the emission of GHGs, because it can convert CO2 and CH4 into syngas. Non-thermal plasma has been investigated for use in DRM and the results demonstrate that plasma can convert CO2 and CH4 into syngas at a lower temperature than catalysis, but the specific energy is relatively high. Combining a catalyst with non-thermal plasma in hybrid system can produce various synergistic effects that reduce specific energy. In this work, BaZr0.05Ti0.95O3 (BZT) with a perovskite structure and ferroelectric property is packed into the plasma reactor to form a hybrid system. The syngas generation efficiency of BZT with a spark discharge reactor is investigated. The spark discharge reactor yields 49.4% conversion of CO2 and 79.0% conversion of CH4 and the BZT packed bed reactor yields 79.0% conversion of CO2 and 84.2% conversion of CH4. With respect to energy utilization, the BZT packed bed reactor has an specific energy of 0.218 MJ/mol, which is 18.7% lower than that of the spark discharge reactor without a ferroelectric (0.268 MJ/mol). Characterization of BZT reveals that the presence of BZT increases the charge density in the plasma reactor, favoring CO2 and CH4 dissociation. Also, SEM and XPS results 3 show that BZT is modified with plasma, resulting in a positive synergy between the plasma and the ferroelectric.

37A hybrid plasma catalytic system consisting of a dielectric barrier discharge (DBD) 38 reactor and relaxor ferroelectrics is investigated for syngas generation via the carbon 39 dioxide reforming of methane. The study tests three kinds of packing materials 40 including two relaxor ferroelectrics BaZr 0.75 T 0.25 O 3 (BZT, ε r = 149), BaFe 0.5 Nb 0.5 O 3 41 (BFN, ε r = 2025) and glass beads (ε r = 3 -5). The BFN and BZT packed bed DBD 42 reactors achieve higher CO 2 and CH 4 conversions and better energy efficiencies for 43 syngas production than the DBD does. On the contrary, the DBD packed with glass 44 beads achieves lower conversions and energy efficiencies than the DBD does. In 45 terms of packings filled in a DBD reactor, there is a tradeoff between an enhancement 46 of the electric field strength and a reduction of the gas retention time. It is interesting 47 that the conversions are increased with the increase of the dielectric constant of the 48 packings tested in the study. Overall speaking, a relaxor ferroelectric with high 49 dielectric constant is a good candidate for constituting the packed-bed DBDs. The 50finding is beneficial to further development of a plasma-based technique for the dry 51 reforming of methane (DRM). 52

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