Simulation of Infrared Extinction Characteristics of Carbon Aerogel Particles

Based on the finite-difference time-domain method, the effects of pore radius (r), porosity(P), and particle radius (R) on the infrared extinction performance of carbon aerogel particles are studied, and the extinction mechanism of carbon aerogel particles is also revealed, which can provide a guide for the development of highly efficient infrared extinction materials. Calculated results show that for infrared of 5 and 8 μm wavelengths, the mass extinction coefficients (MECs) of carbon aerogel particles show a trend of first increasing and then decreasing with the increase of r or R, while they continue to increase with the increase of P. At a specific wavelength, carbon aerogel particles have optimal r and optimal R, and at this time, the MECs have maximum values. The values of optimal r increase with the increase of P, while for different porosities, the values of optimal R are basically the same. The attenuation of infrared radiation by carbon aerogel particles is mainly absorption attenuation, which varies less with r, increases with the increase of P, and decreases with the increase of R. Under the action of an external electromagnetic field, the π-electrons in the carbon aerogel skeleton undergo a localized surface plasmon effect. With the increase of porosity, the electric field strength and the electric field enhancement region at the particle holes increase, and more light energy is converted into heat energy and dissipated.