• IR thermography tracks the wetting front one-to-one with optical imaging. • Washburn scaling holds across all plasma activation conditions (z ∝ t 0.5 ). • Plasma activation tunes wettability: O 2 enhances hydrophilicity whereas H 2 attenuates it (time-dependent). • Heat release increases with wetting-front speed: O 2 elevates and H 2 suppresses it. • Data collapse via Eckert-number correlation with capillary number and wettability ( 1 + cos θ ).
Ushakov et al. (Mon,) studied this question.