Characterisation of rare earth selective emitters for thermophotovoltaic applications

Abstract We investigate selective radiation emitters made from rare earth oxides suitable for thermophotovoltaic (TPV) systems. Yb 2 O 3 and Er 2 O 3 emitters were fabricated and their radiation power, temperature and emissivity were measured in the entire relevant spectral range. We found temperatures of 1735 K for the Yb 2 O 3 emitter and of 1680 K for the Er 2 O 3 emitter both heated with a 1.35 kW butane burner. The maximum emissivities of the selective peaks were 0.85 at 1.27 eV, and 0.82 at 0.80 eV for the Yb 2 O 3 and the Er 2 O 3 emitter, respectively. The emission spectra show gas emission lines originating from the combustion process in addition to the selective emission bands. An estimation based on a simplified combustion model show that a TPV system with a system efficiency of about 10% can be realised using an Yb 2 O 3 emitter, silicon photocells and a perfect selective filter.