Highly enhanced infrared spectral emissivity of porous CeO2 coating

A porous CeO2 coating was prepared by electron beam physical vapor deposition technique. The microstructure and infrared spectral emissivity in wavelength range 2.5∼25 μm were investigated. The surface morphology could be tuned by deposition power density. The as-deposited coating shows (311)-preferred orientation. The great enhancement of infrared spectral emissivity in the whole wavelength range was observed in the porous CeO2 coating, compared to a dense CeO2 coating. The porous surface structure provides multiple reflection and absorption, thus improves the spectral emissivity. Moreover, the CeO2 coating also shows excellent adhesion property to nickel-based alloy substrate. These results show a potential application at high temperature.

► Porous CeO2 coating is prepared on Ni based substrate by EB-PVD.
► The infrared spectral emissivity at high temperature is studied.
► Porous CeO2 coating shows highly enhanced emssivity in the mid-infrared region.
► The emissivity enhancement mechanism is discussed for the porous CeO2 coating.