Open Access

ARTICLE

Properties of Bi₂O₂S Thin Films Produced by Chemical Bath Deposition at Different Immersion Bath Numbers

Edgar G. Zamorano-Noriega¹, María E. Martínez-Barbosa^1,*, María L. Mota², Ana B. López-Oyama^3,4, Eugenio Rodríguez González⁵, Crescencio García-Guendulain⁶, Ramón Ochoa-Landín⁷, Fernando J. Sánchez-Rodríguez^8,*, Santos J. Castillo^3,*

1 Departamento de Investigación en Polímeros y Materiales, Universidad de Sonora, Blvd. Luis Encinas S/N, Hermosillo, Mexico
2 Secihti-InnovaBienestar de México, Ciencia y Tecnología #790, Col Saltillo 400, Saltillo, 25290, Coahuila, Mexico
3 Departamento de Investigación en Física (DIFUS), Universidad de Sonora, Blvd. Luis Encinas S/N, Hermosillo, Mexico
4 Secihti-DIFUS, Universidad de Sonora, Blvd. Luis Encinas S/N, Hermosillo, Mexico
5 Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada-Unidad Altamira, Instituto Politécnico Nacional, km 14.5 Carr. Puerto Industrial, Altamira, Mexico
6 Escuela de Ingeniería y Ciencias, Tecnológico de Monterrey, Mexico City, Mexico
7 Departamento de Física, Universidad de Sonora, Blvd. Luis Encinas S/N, Hermosillo, Mexico
8 Facultad de Ciencias Físico-Matemáticas, Universidad de Autónoma de Sinaloa, Culiacán, Mexico

* Corresponding Authors: María E. Martínez-Barbosa. Email: ; Fernando J. Sánchez-Rodríguez. Email: ; Santos J. Castillo. Email:

Chalcogenide Letters 2026, 23(6), 6 https://doi.org/10.32604/cl.2026.085590

Received 14 May 2026; Accepted 10 June 2026; Issue published 02 July 2026

Abstract

The major challenge in developing efficient photovoltaic devices is achieving highlight absorption, optimal charge transport, and low recombination losses. In this work, the effect of the immersion bath numbers in the chemical bath deposition (CBD) technique on the properties of bismuth oxysulfide (Bi₂O₂S) thin films, as emergent materials, was studied. The films were synthesized under eco-friendly conditions, using a low-concentration bismuth nitrate precursor and thioacetamide as the sulfur source, and under basic conditions at moderate temperature, with a reaction time of 3 h. X-ray diffraction demonstrated the formation of a crystalline Bi₂O₂S phase, and the morphological analysis showed a uniform film coverage with flower-like morphology, indicating anisotropic growth. XPS verified the coexistence of bismuth, oxygen, and sulfur, confirming the formation of the oxysulfide compound. Results demonstrated that absorbance increased as the number of immersion bath numbers increased. Indeed, structural analysis established that the number of immersion baths critically influences crystallite size, interlayer spacing, and crystallinity of Bi₂O₂S nanosheets. Finally, a formation mechanism is proposed for these Bi₂O₂S thin films for the one-, two-, and three-immersion bath. This study demonstrates that CBD processing parameters critically influence film quality and phase purity, offering an effective and low-cost route to produce Bi-based thin films with potential applications in photovoltaic devices.

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Keywords

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Supplementary Material

Supplementary Material File

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