Sustainable recycling of spent lead-acid batteries into perovskite thin films via inkjet printing for solar energy

Abstract The disposal of spent lead-acid batteries represents a critical environmental challenge due to their toxic waste content. This study presents a sustainable solution by recycling lead from non-reusable lead-acid batteries to synthesize lead halides (PbX 2 ), key precursors for perovskite materials in solar cells. This innovative approach minimizes environmental pollution while converting hazardous waste into high-value materials for renewable energy applications. Lead halides (PbI 2 , PbCl 2 , PbBr 2 ) were synthesized under optimized conditions and characterized comprehensively using XRD, XPS, TEM, absorption spectroscopy, optical band gap analysis, and photoluminescence (PL) spectroscopy. These materials were then employed to fabricate CH 3 NH 3 PbI 3 thin films via inkjet printing at 1.0 M and 1.3 M concentrations. Structural and optical analyses of the thin films confirmed a tetragonal perovskite phase, with a reduction in crystallite size (36.8 to 31.3 nm) and a slight decrease in band gap (1.557 to 1.546 eV) at higher concentrations, enhancing light-harvesting properties. Additionally, a lead halide recovering cost assessment highlighted the economic viability of this recycling process. This scalable, eco-friendly approach offers a cost-effective pathway for sustainable solar energy technologies. Graphical abstract