Density functional theory studies on the mechanism of activation of methane by homonuclear bimetallic Ni-Ni

► We report the reaction mechanism of CH4 catalyzed by homonuclear bimetallic Ni-Ni. ► The reaction proceeds with isomerization and H2 elimination. ► The isomerization reaction is preferred to the H2 elimination reaction. ► The homonuclear bimetallic Ni-Ni shows superior catalytic activity.