Open AccessSpectrally shaping high-temperature radiators for thermophotovoltaics using Mo-HfO2 trilayer-on-substrate structures
Author(s) -
Etienne Blandre,
Makoto Shimizu,
Asaka Kohiyama,
Hiroo Yugami,
PierreOlivier Chapuis,
Rodolphe Vaillon
Publication year - 2018
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.26.004346
Subject(s) - thermophotovoltaic , materials science , optoelectronics , optics , substrate (aquarium) , thin film , hafnia , molybdenum , layer (electronics) , nanotechnology , ceramic , composite material , cubic zirconia , common emitter , oceanography , physics , metallurgy , geology
Easy-to-fabricate, high-temperature, thermally-stable radiators are critical elements for developing efficient and sustainable thermophotovoltaic energy conversion devices. In this frame, a trilayer-on-substrate structure is selected. It is composed of a refractory metal -molybdenum - constituting the substrate and an intermediate thin film sandwiched between two hafnia transparent layers. An in-depth analysis shows that two spectrally distinct interference regimes take place in the hafnia layer-molybdenum thin film substructure, and that backward and forward thermally-emitted waves by the thin film are selected in two distinct interferential resonating cavities. The interference regimes within and between these cavities are key to the spectral shaping of thermal emission. The radiative performances of the structures are evaluated by introducing a figure of merit. Using the example of a GaSb cell, it is shown that the structure can be optimized for providing the broadband large emission with a steep cutoff required for mitigating photoconversion losses.