A dual-function non-thermal plasma system was successfully employed for the Pd nanoparticles preparation, followed by in- plasma catalytic methane partial oxidation to liquid oxygenates and fuels. Non-thermal plasma treated catalyst (P-Pd/SBA-15) was found to possess better surface characteristics to provide the best liquid oxygenates selectivity of 70%, while it restrained to only 58% in only plasma mode. © 2020 Elsevier B.V.