Bimetal oxide catalyst and methods, a method comprises: mixing and grinding to obtain a mixture comprising a manganese salt (a), at least one of other metal salt (b), and an additive (c), wherein the other metal salt comprises at least one of a copper salt, a cobalt salt, a cerium salt, an iron salt, or a nickel salt, and the additive comprises at least one of polyol or organic acid, and calcining the mixture to obtain the bimetal oxide catalyst.