The Study Of A Novel Carbon Nanotube-Based Infrared Thermal Radiation Coating

High-emissivity coatings have been widely used in diverse applications,such as stray light control,bolometric measurement of earth and solar irradiance,and black body sources,etc.In the exploration of the materials with highest emissivity,we found that the black coatings doped with carbon nanotubes have excellent infrared irradiance.In order to explore the characteristics of carbon nanotube-based infrared thermal radiation coatings,this thesis studied preparation methods of such coatings.We have proved that the infrared emissivity of the commercial black paint(VC811-21)can be greatly enhanced via theoretical calculations based on bidirectional reflectance distribution function,normalized randomly distributed roughness,geometric optics approximation and infrared emissivity measurements.The black paint was deposited on the aluminum cylindrical substrates by spraying method.The microstructure of the prepared samples were characterized by the Raman spectrometer,probe surface profiler,and scanning electron microscope.By optimizing the concentration of MWCNT to be 1‰,a coating sample with low surface roughness and free of cracks was obtained.Then,the emissivities of the coating samples in the atmosphere and vacuum environment were measured using the heat mask and the vacuum radiation temperature emissivity measurement methods.We found that in the wavelength range of 6.5-16?m,the highest averaged infrared emissivity of the optimized sample in vacuum can be as high as 0.985,which is much higher than VC811-21(0.964)and other commercial black paints.These results indicate that M WCNT-doped black paint can be a potential high-quality black paint material,which greatly promotes the design of new black bodies for the next generation of infrared remote sensing.