Temperature–humidity wireless sensor powered by a wide-bandgap perovskite solar cell

In this work, we present a self-powered temperature–humidity sensor prototype based on a wide-bandgap perovskite solar cell (PSC) integrated with a supercapacitor for indoor applications. The device utilizes a 12 cm2 perovskite solar cell based on Cs0.17FA0.83Pb(I0.6Br0.4)3 absorber material with a bandgap of 1.75 eV, optimized for low-intensity artificial light and achieving a power conversion efficiency of 22.1% under 800 lux LED illumination. The sensor operates under the ZigBee 3.0 protocol and is capable of wireless communication with a hub gateway. A custom-designed energy management circuit enables stable power delivery by regulating voltage from the PSC-charged supercapacitor, ensuring uninterrupted sensor operation. The prototype demonstrated up to 87 h of autonomous functionality under 1000 lux and stable long-term operation at ≥ 3000 lux. Comparative studies show superior or comparable performance of PSCs over commercial Si solar cells of the same active area under indoor lighting. This work highlights a viable, battery-free energy solution for sustainable, long-term indoor IoT device operation.