Synthesis of manganese oxide thin films deposited on different substrates via atmospheric pressure-CVD

• Published in: Surface & coatings technology 2024-10, Vol.494, p.131440, Article 131440
• Main Authors: Pérez-Diaz, P.J., Esqueda-Barrón, Y., Baas-López, J.M., Cuentas-Gallegos, A.K., Pacheco-Catalán, D.E.
• Format: Article
• Language: English
• Subjects: Atmospheric pressure CVD; MnxOy; Thin films
• ISSN: 0257-8972
• DOI: 10.1016/j.surfcoat.2024.131440

In this study, we report the synthesis of manganese oxide (MnxOy) thin films on stainless steel, silicon, and borosilicate glass substrates via atmospheric pressure chemical vapor deposition (AP-CVD) using Mn(thd)3 and O3 as precursor and reactive gas, respectively. Deposition was achieved at a low temperature of 300 °C under atmospheric pressure, offering a cost-effective and scalable alternative to traditional high-vacuum CVD methods. The films displayed excellent adhesion and reproducibility, with substrate-dependent variations in film coloration, crystal phases, and morphology. X-ray diffraction (XRD) and Raman spectroscopy confirmed the presence of Mn3O4 and Mn2O3 phases, with Mn3O4 predominating on stainless steel and silicon, while Mn2O3 was more prominent on glass. Scanning electron microscopy (SEM) revealed granular structures with uniform grain sizes, particularly on stainless steel substrates. X-ray photoelectron spectroscopy (XPS) confirmed Mn2+ and Mn3+ oxidation states, consistent with the phase distribution observed by XRD and Raman analysis. This work demonstrates the potential of AP-CVD for scalable manganese oxide thin-film synthesis, particularly for energy storage applications, where Mn3O4 and Mn2O3 can serve as precursors to δ-MnO2 in supercapacitors. The method's simplicity, combined with the high-quality films produced, makes it a promising approach for future research and industrial-scale applications. •Manganese oxides are useful in catalysis, water treatment, medicine, biosensors, energy storage.•AP-CVD can deposit Mn3O4 + Mn2O3 thin films on various substrates under scalable conditions.•Crystalline substrates (SS, Si) favor Mn3O4; amorphous substrates (glass) favor Mn2O3.•Synthesized films ranged in thickness from 50 to 80 nm.