PROJECT TITLE :

Sputtered Tantalum Photonic Crystal Coatings for High-Temperature Energy Conversion Applications

ABSTRACT:

Recent advances in photonic crystals have enabled high-efficiency thermophotovoltaic (TPV) energy conversion by permitting near-perfect spectral management. During this paper, photonic crystals fabricated in thick tantalum (Ta) coatings, sputtered onto a metallic substrate, were investigated as a potential replacement for photonic crystals fabricated in bulk refractory metal substrates in TPV applications. A a pair of-D photonic crystal was fabricated in an exceedingly thirty-μm thick Ta sputtered coating using normal semiconductor processes as a symbol-of-concept for a selective emitter/solar absorber. The reflectance of the fabricated photonic crystal coating was characterized before and once one h anneals at 70zero, 90zero, and 110zero °C, and after a twenty four h anneal at 900 °C. To guard its surface throughout the anneals, a skinny conformal hafnia (HfO2) layer was deposited by atomic layer deposition on the photonic crystal. The photonic crystal showed high spectral selectivity in smart agreement with numerical simulations and sustained the anneals with minimal structural degradation or amendment in its optical properties. This study presents a promising different to bulk substrates as a comparatively low-cost and easily integrated platform for nanostructured devices in high-temperature energy conversion systems.