Fabrication of an Omnidirectional 2D Photonic Crystal Emitter for Thermophotovoltaics

16th International Conference on Micro and Nanotechnology for Power Generation and Energy Conversion Applications

物理学;能源学

Stelmakh, V.^1,2 ; Chan, W.R.^1 ; Ghebrebrhan, M.^3 ; Soljacic, M.^4 ; Joannopoulos, J.D.^1,4 ; Celanovic, I.^1

Institute for Soldier Nanotechnologies, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge

MA

02139, United States^1

Department of Electrical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge

MA

02139, United States^2

U.S. Army Natick Soldier Research Development and Engineering Center, 1 4th Ave., Natick

MA

01760, United States^3

Department of Physics, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge

MA

02139, United States^4

关键词: 2-D photonic crystals;    Dielectric filling;    Experimental demonstrations;    Fabrication process;    Thermal characterization;    Thermophotovoltaic systems;    Thermophotovoltaics;    Two-dimensional photonic crystals;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/773/1/012037/pdf
DOI  :  10.1088/1742-6596/773/1/012037

来源: IOP

【 摘 要 】

In a thermophotovoltaic (TPV) system, a heat source brings an emitter to incandescence and the spectrally confined thermal radiation is converted to electricity by a low-bandgap photovoltaic (PV) cell. Efficiency is dominated by the emitter's ratio of in-band emissivity (convertible by the PV cell) to out-of-band emissivity (inconvertible). Two-dimensional photonic crystals (PhCs) offer high in-band emissivity and low out-of-band emissivity at normal incidence, but have reduced in-band emissivity off-normal. According to Lambert's law, most thermal radiation occurs off-normal. An omnidirectional PhC capable of high in-band emissivity at all angles would increase total in-band power by 55% at 1200°C. In this work, we present the first experimental demonstration an omnidirectional hafnia-filled 2D tantalum PhC emitter suitable for TPV applications such as combustion, radioisotope, and solar TPV. Dielectric filling improved the hemispherical performance without sacrificing stability or ease of fabrication. The numerical simulations, fabrication processes, and optical and thermal characterizations of the PhC are presented in this paper.