Carbon nanotube-based tandem absorber with tunable spectral selectivity: transition from near-perfect blackbody absorber to solar selective absorber

N Selvakumar; S B Krupanidhi; Harish C Barshilia

doi:10.1002/adma.201305070

Carbon nanotube-based tandem absorber with tunable spectral selectivity: transition from near-perfect blackbody absorber to solar selective absorber

Adv Mater. 2014 Apr 23;26(16):2552-7. doi: 10.1002/adma.201305070. Epub 2014 Jan 28.

Authors

N Selvakumar¹, S B Krupanidhi, Harish C Barshilia

Affiliation

¹ Nanomaterials Research Laboratory, Surface Engineering Division, CSIR-National Aerospace Laboratories, Bangalore, -560 017, India; Materials Research Centre, Indian Institute of Science, Bangalore, -560 012, India.

PMID: 24474148
DOI: 10.1002/adma.201305070

Abstract

CVD grown CNT thin film with a thickness greater than 10 μm behaves like a near-perfect blackbody absorber (i.e., α/ε = 0.99/0.99). Whereas, for a thickness ≤ 0.4 µm, the CNT based tandem absorber acts as a spectrally selective coating (i.e., α/ε = 0.95/0.20). These selective coatings exhibit thermal stability up to 650 °C in vacuum, which can be used for solar thermal power generation.

Keywords: blackbody absorber; carbon nanotubes; high temperature absorber coatings; reflectance; spectral selectivity.