Diesel oxidation catalysts, catalytic articles, methods of making catalytic articles, emissions treatment systems and methods of treating an exhaust gas stream using the catalytic articles for the treatment of exhaust gas emissions, such as the oxidation of unburned hydrocarbons (HC) and carbon monoxide(CO) are described. Specific catalytic articles comprising a substrate with a first washcoat layer comprising greater than or equal to about 2% by weight palladium dispersed on a cerin support and a second washcoat layer comprising a platinum group metal and a refractory metal oxide are described.