Magnesium diboride: An effective light-to-heat conversion material in solid-state

摘要

We report herein a giant light-to-heat transduction observed in bulk magnesium diboride (MgB2) on exposure to incoherent, continuous wave, broadband light-sources. The heat-flow from the sample was accurately determined using photocalorimetry, to register an ultrahigh value of 45 W/g upon irradiation with a low-pressure mercury vapour lamp (λ ~ 250-450 nm; irradiance ~800 mW/cm2) with a photo-to-thermal conversion efficiency of about 83% (with an error of ±1.86%). As a practical application, light-induced heat was used to generate electrical power using a thermoelectric generator (open voltage ~125mV, when illuminated by a solar simulator). The bulk MgB_2 powder was found to be photo-stable under different irradiation conditions, and the photothermal effect was found to be highly reproducible.