Fig. 2: Surface characterization, wettability, and versatility of F-DLC coatings.

a TDTR thermal reflectivity as a function of the time delay Δt between pump and probe pulses on the F-DLC coating. The measured thermal conductivity was k = 0.46 ± 0.05 W m⁻¹ K⁻¹. The TDTR sample consisted of a 111 nm sputtered Al layer on a 1650 nm F-DLC multilayer stack. b X-ray photoelectron spectroscopy (XPS) of the C1s peak demonstrating the three components consisting of sp³ (C–C) bonds at 285.2 eV, sp² (C=C) bonds at 284.4 eV, and C–O or C=O bonds at 286.6 eV. c The XPS F1s spectrum showed the highest amount of fluorine atoms are bonded with carbon by covalent and semi-ionic C–F bonds. d Surface energy and Young’s modulus of different commonly used engineering materials, showing that F-DLC combines the merit of both low surface energy and high mechanical modulus. e Measured apparent advancing and receding contact angles of DI water droplets on a variety of substrates coated with F-DLC. Here, the error bars indicate the standard deviation, which was determined based on three spatially independent measurements conducted for each data point. f Optical microscopy top-view images of atmospheric water vapor condensation on the different F-DLC coated substrates, showing the substrate versatility with similar hydrophobicity of the F-DLC coating.