Ni–Mg Supported Catalysts on Low-Temperature Electrocatalytic Tri-reforming of Methane with Suppressed Oxidation

10wt%Ni–10wt%Mg–La 0.1 Zr 0.9 O 2– x (LZO) catalyst shows high reforming activity of methane while suppressing methane combustion on tri-reforming of methane at low temperatures of 473 K in an electric field. On the basis of results of light-on and light-off tests for methane oxidation and temperature dependencies for catalytic methane steam reforming activity with or without the electric field, we found that Mg addition to 10wt%Ni–LZO catalyst suppresses methane combustion, while the methane steam reforming proceeds well by virtue of surface protonics in the electric field. Ni 2+ on 10wt%Ni–10wt%Mg–LZO catalyst was more cationic than that on 10wt%Ni–LZO catalyst, and NiO–MgO solid solution formed on LZO support played an important role in combustion suppression.