Stoichiometric early transition metal oxide cations (TiO(2))(1-5)(+), (ZrO(2))(1-4)(+), (HfO(2))(1-2)(+), (V(2)O(5))(1-5)(+), (Nb(2)O(5))(1-3)(+), (Ta(2)O(5))(1-2)(+), (MoO(3))(1-2)(+), (WO(3))(1-3)(+), and Re(2)O(7)(+) are able to activate the C-H bond of methane under near room temperature conditions.