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The hydrogenation of CO 2 to methane over a 20 wt% Ir/TiO 2 catalytic coating has been investigated in a tubular dielectric barrier discharge (DBD) reactor. The 1.2 µm Ir/TiO 2 coating was deposited onto the inner wall of a quartz tube by a combustion-evaporation method from a mixture containing a Ti precursor and a colloidal suspension of Ir nanoparticles (2 nm). The catalyst was characterised by XRD, SEM, TEM/EDS and CO chemisorption. The Ir(0) state in the as-synthesised film was confirmed by XPS. The CH 4 conversion increased by 1.5 times, as compared to an empty tube. A maximum CO 2 conversion rate of 2.1 μmol s−1 was achieved at a fuel production efficiency of 3.5%. Surface reactions onto the catalyst surface are responsible for enhancement of reaction rate. The results presented in this work open up new possibilities in plasma-catalysis, whereby efficient reactions can be carried out over small volumes of catalyst. [Display omitted] • The highest CO2 conversion was observed over Ir/TiO2 at the same level of energy efficiency. • The particle size and dispersion remained essentially the same after 3 h on stream in plasma. • Methane was the main reaction product in the catalytic pathway. • IrO2 phase is responsible for high catalytic activity. [ABSTRACT FROM AUTHOR]