Comparative analysis of voltage losses in perovskite and GaAs solar cells at low temperatures

This study presents a comparative analysis of the open circuit voltage behavior of perovskite vs gallium arsenide (GaAs) solar cells at low temperatures relevant to space applications. While GaAs solar cells demonstrate high power conversion efficiencies and superior environmental stability, their widespread adoption is limited by high manufacturing costs. In contrast, perovskite solar cells have emerged as a promising alternative due to their high efficiency, excellent optoelectronic properties, and low fabrication costs. To evaluate and compare their optoelectronic characteristics and voltage losses at low temperatures, we have characterized both devices using temperature-dependent current–voltage (J–V) and photoluminescence-based radiative efficiency measurements in the range of 300–160 K. GaAs devices exhibited a linear increase in open-circuit voltage (Voc) with decreasing temperature, consistent with theory. In contrast, perovskite devices showed suppressed Voc enhancements and an S-shaped J–V response below 240 K. Using temperature-dependent external radiative efficiency measurements, we show that temperature-dependent entropic losses related to nonradiative recombination are higher in perovskite devices compared to GaAs at high temperatures, but the gap between the two shrinks substantially at lower temperatures. These findings provide valuable insight into temperature-dependent Voc in perovskite solar cells, particularly relevant for space deployment applications.