Indoor bifacial perovskite photovoltaics: Efficient energy harvesting from artificial light sources

Abstract

Emerging bifacial photovoltaics (BPVs) have received tremendous attention due to their high efficacy and economical cost by harvesting more light energy in outdoor conditions. Although, the performance of BPVs in outdoor conditions is severely limited by the albedo light (light reflected from the surface, soil, clouds, etc.). Conversely, BPVs could also be utilize to efficiently harvest energy from indoor environments such as offices, homes, large gathering halls, stations, and more, where multiple artificial lighting sources are employed. In this work, we have designed an efficient indoor bifacial perovskite photovoltaics (i-BPPVs) with the capability of harvesting maximum light from both top and bottom sides. The i-BPPVs were designed and fabricated in a stack of organic–inorganic hybrid perovskite material amid a transparent bottom electrode (ITO), and top (Au/ITO) electrode. The fabricated i-BPPVs exhibited an efficiency of 30.3%, short circuit current density (JSC) of 148.3 µA cm−2, open circuit voltage (VOC) of 0.93 V, and fill factor (FF) of 71.7% when artificial LED light source of 1000 lx is exposed from the top side, whereas an efficiency of 22.1%, JSC of 116.2 µA cm−2, VOC of 0.89 V, and FF of 69.4% have been obtained from the bottom side. The champion bifacial i-BPPVs display an excellent bifaciality factor (Φ) of 0.73 and demonstrated superior operational stability when subjected to continuous illumination. Moreover, this work of designing i-BPPVs will be a pivotal step towards advancing cost-effective and efficient technology for harvesting more energy from artificial indoor light sources.