Simulating and characterizing carbon based solar thermal absorbers

Abstract

The main objective of this project is to determine and characterize the optical and structural properties of carbon nanotube (CNT) coated aluminum substrates to facilitate better understanding regarding their suitability for solar absorption. In this way, it may be possible to utilize this material to produce improved and more efficient spectrally selective solar thermal absorbers in solar thermal collectors. The project started with a collaboration on characterization of Zhonghua's CNT samples and changed more to simulation of various carbon materials.

This project includes simulations for reflectance of seven different carbon materials at a variety of thickness levels in order to observe the variation of reflectance in visible and infrared wavelength regions, as well as their respective absorptance and emittance. An anti reflection coating was also added in order to increase the absorptance values. The samples prepared by Zhonghua Chen (PhD Candidate) were utilized in surface morphology by application of scanning electron microscopy to investigate the properties of an absorbing surface, such as structure, uniformity, porosity, CNT alignment and homogeneity. Energy dispersive x-ray spectroscopy was also conducted in the characterization of various elements.