Electrochemical Processing of Inverted Perovskite Solar Cells for Improved Morphological Uniformity and Scalable Fabrication

Sergio Reyes^1,2, Pablo Ortiz¹, María Teresa Cortès¹, Michael Saliba²

¹ Universidad de los Andes, Bogotá 111711, Colombia

² Institut für Photovoltaik (ipv), University of Stuttgart, Stuttgart 70569, Germany

*Corresponding author(s): se.reyes@uniandes.edu.co (S. Reyes)

Abstract

Inverted perovskite solar cells (PSCs) have emerged as a highly promising photovoltaic technology due to their simple device architecture, low-temperature processing, and compatibility with flexible substrates. However, fabrication of the perovskite absorber layer in inverted PSCs commonly relies on spin coating, a method that offers excellent control at laboratory scale but presents significant challenges for large-area manufacturing and process reproducibility. Developing alternative deposition strategies that enable scalable fabrication while maintaining high film quality remains essential for the commercial deployment of perovskite photovoltaics. In this work, an electrochemical deposition route was developed for the fabrication of inverted PSCs, aiming to improve morphological uniformity, enhance optoelectronic properties, and eliminate the need for controlled-atmosphere processing. Nickel oxide (NiO) and lead oxide (PbO) precursor layers were sequentially deposited onto conductive glass substrates via pulse voltammetry. These precursor films were subsequently converted into methylammonium lead iodide (MAPI) perovskite through chemical treatment with hydroiodic acid and methylammonium iodide. To complete the device architecture, PCBM and BCP were deposited as the electron transport and interfacial layers, respectively, followed by thermal evaporation of silver contacts.

Comprehensive characterization was performed using scanning electron microscopy (SEM), UV–Vis spectroscopy, photoluminescence, X-ray diffraction (XRD), contact angle analysis, and photovoltaic measurements under simulated solar illumination. The electrochemical approach enabled the formation of highly homogeneous and compact perovskite films with improved surface coverage and crystallinity, resulting in enhanced charge transport and reduced recombination losses. As a consequence, the fabricated devices achieved a power conversion efficiency (PCE) of 15%, demonstrating substantial performance improvements compared with conventional processing routes. These results establish electrochemical deposition as a scalable, low-cost, and highly controllable strategy for the fabrication of inverted perovskite solar cells. The proposed methodology provides a promising pathway toward large-area manufacturing of efficient perovskite photovoltaic devices while reducing processing complexity and environmental constraints.