PbI2 Refinement from Lead-Acid Battery as Potential Precursor for Hybrid Lead Halide Perovskite Solar Cells

BERRUET, MARIANA; CÓRDOBA, MATÍAS A.; TARETTO, KURT R.; SPERA, ENZO L.; MOLINA, NICOLÁS; PEREYRA, C. JAVIER; MAROTTI, RICARDO E.; GAU, DANIEL L; MONTI, ANALÍA V.

Mar del Plata

Encuentro; 34th Topical Meeting of the International Society of Electrochemistry; 2023

INTEMA- División Electroquímica Aplicada

Large amounts of waste lead-acid batteries are generated every year, battery waste seriously polluting the environment and constituting a persistent threat to human health. An Argentine company dedicated to the manufacture of batteries, manages the hazardous waste cycle by applying a circular economy through the recycling of used batteries [1] and generating new added value products. Here we focus on producing lead-iodide (PbI2) precursor from disused Pb-acid batteries with the aim of studying its potential use in hybrid lead halide perovskite solar cells (PSCs), following a procedure according to ref. [2].Within the framework of metalorganic perovskite semiconductors for photovoltaics, the traditional absorption material CH3NH3PbI3 is mainly synthesized by the reaction of PbI2 precursor and methylammonium iodide (CH3NH3I). The achievement of a compact and dense perovskite layer is critical for high performance PSCs devices, which is a key strategy for minimizing crystalline defects and therefore reducing carrier recombination losses in polycrystalline perovskite films. Furthermore, impurities and/or stoichiometric defects can lead recombination centers in the bulk and at the interfaces with charge collecting layers. Evidence of the consequence of low quality precursors on the output characteristics of PSCs can be seen in Figure 1. The evident strong reduction in efficiency in the device with untreated PbI2 precursor (red circles in Fig. 1) reveals that it is mandatory achieve a high precursor quality from low-grade sources to produce efficient PSCs.In this work, we adopted a method to eliminate impurities and refine the as-received PbI2 precursor based on re-crystallization [3]. Thin CH3NH3PbI3 films were deposited by spin-coating following the one-step route in an N2-filled glovebox. The obtained films were contrasted to films prepared by commercially available PbI2, as reference. The PbI2 precursor has been studied by structural, optical and opto-electrical characterization methods at different stages of refinement, as well as the resulting thin perovskite films and PSCs devices.