Description
A highly reflective rear mirror can increase the efficiency of thermophotovoltaics through the regeneration of unused photons. Based on this concept, we recently demonstrated a record 29.1% thermophotovoltaic device efficiency. We have also identified the challenges as we aim towards 50% thermophotovoltaic efficiency, mainly device sub-bandgap reflectivity, material quality, carrier collection as well as test chamber geometry. Here, we present an analysis of each of these factors, and ways to mitigate these challenges.