An ecofriendly solventless mechano-chemical synthesis was developed for the preparation of Pd/CeO2 methane oxidation catalysts, which exhibited outstanding results in terms of catalytic activity and stability. Their enhanced reactivity coupled with their peculiar morphology prompted a systematic study of these catalysts in order to gain a better understanding of methane activation and deeper insights into the correlation between methane activation and Pd-Ce interaction, specifically at nanoscale level.