Device Engineering of a Novel Lead-Free Solar Cell Architecture Utilizing Inorganic CsSnCl3 and CsSnI3 Perovskite-Based Dual Absorbers for Sustainable Powering of Wireless Networks

As the Internet of Things (IoT) expands, the demand for reliable and autonomous power sources for small, distributed devices continues to grow. With proper integration, perovskite solar cell (PSC) architecture can ensure that wireless nodes have a continuous power supply, which is critical for the reliable operation of wireless networks, especially in remote or harsh environments. Therefore, this article proposes a novel design of cesium tin iodide (CsSnI3) and cesium tin chloride (CsSnCl3)-based dual perovskite absorber composition sandwiched between a titanium dioxide (TiO2) electron transport layer (ETL) and Spiro-OMeTAD hole transport layer (HTL) to form an indium tin oxide (ITO)/TiO2/CsSnCl3/CsSnI3/Spiro-OMeTAD/Ag heterojunction solar cell architecture. The critical device parameters, including absorber layer and carrier transport layer thickness, defect density, temperature, doping concentration, and series and shunt resistance, are thoroughly optimized and evaluated using a solar cell capacitance simulator (SCAPS-1D). Peak power conversion efficiency (PCE) of 24%, short-circuit current (J(SC)) of 28.5 mA/cm(2), open-circuit voltage (V-OC) of 0.96 V, and fill-factor (FF) of 85.87% under AM 1.5 photo illuminance at a device defect density of 10(15) cm(-3) are obtained. The proposed dual-absorber composition notably outperforms the mere 12.96% and 9.66% PCE attained with the reported CsSnI3- and CsSnCl3-based single-absorber PSC counterparts. Moreover, by implementing the proposed CsSnI3/CsSnCl3 dual-absorber composition, improved quantum efficiency (QE) of 90% is achieved across a spectral range of 400-1000 nm. The all-inorganic absorber-based PSC composition will reduce reliance on traditional power sources, promoting greener and more sustainable energy-intensive sensors and applications, such as real-time monitoring and data analytics within the network. The proposed PSC, comprising a single module with an area of 100 cm(2) and PCE of 24%, can generate 2.736 W of green power under standard test conditions. Consequently, a solar panel comprising 88 PSCs could support approximately 48 wireless sensor nodes, each consuming 5 W of power.