We present an innovative approach for reacting carbon dioxide and water to give syngas by combining heterogeneous catalysis and non-thermal plasma techniques. This approach utilizes an abundant water and nickel catalyst, and mitigates the thermodynamic penalty by using a Dielectric Barrier Discharge (DBD) plasma reactor. Argon dilution was used in the experiment to reduce the exothermic recombination of hydrogen and oxygen, which is considered as the major hurdle for H 2 O conversion. As a result, the syngas ratio was dramatically improved from 0.07 to 0.86. In addition, the conversions of CO 2 and H 2 O were improved by packing Ni/γ-Al 2 O 3 catalysts into the DBD reactor. The yields of H 2 and CO were up to 13.8% and 5.6% respectively. The conditions for plasma catalysis and the catalyst characterization are presented and discussed.

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Non-thermal plasma is a promising technology for high purity nanomaterial synthesis in a fast, flexible and controllable process. Gliding arc discharge, as one of the most efficient non-thermal plasmas, has been widely used in gas treatment but rarely studied for the nanomaterial synthesis. In this study, a comparison study for carbon nanosheets synthesis including toluene dissociation and graphite exfoliation was investigated in a 2D gliding arc reactor at atmospheric pressure. The effects of gas flow rate, precursor concentration and power input on the structures of carbon nanosheets produced through the two synthesis routes were explored and compared. Amorphous carbon nanosheets were produced in both approaches with a few crystalline structures formation in the case of toluene dissociation. The thickness of carbon nanosheets synthesized from graphite exfoliation was less than 3 nm, which was thinner and more uniform than that from toluene dissociation. The flow rate of carrier gas has direct influence on the morphology of carbon nanomaterials in the case of toluene dissociation. Carbon spheres were also produced along with nanosheets when the flow rate decreased from 2 to 0.5 L/min. However, in the case of graphite exfoliation, only carbon nanosheets were observed regardless of the change in flow rate of the carrier gas. The generated chemical species and plasma gas temperatures were measured and estimated for the mechanism study, respectively.