Bismuth ferrite (BiFeO3, abbreviated as BFO) has great potential for environmental applications. It performs well in the remediation of pollutants from the environment, for example as a toxic gas sensor or a photocatalyst for the degradation of dyes. Moreover, it presents a strong photovoltaic effect [1,2]. The topography and surface area of a material significantly affect its properties. Thus, it is of significance to study the surface characteristics of the material.
In this work, we prepared a set of pure BFO nanostructred films deposited on glass via the spin-coating-assisted sol–gel method, using bismuth nitrate pentahydrate (Bi(NO3)3·5H2O) and iron nitrate nonahydrate (Fe(NO3)3·9H2O) as starting materials and ethylene glycol as solvent, with a different number of deposition cycles in order to investigate its effect on morphological properties.
The atomic force microscopy AFM confirmed this effect, and showed that the root mean square (Rq) of the surface roughness increases after increasing the number of cycles (from 3 to 10 cycles) reaching a value of ≈6 nm. Based on AFM surface topography maps, we found that the median grain sizes also increase from ≈35 nm to ≈55 nm. However, both the dislocation density and the specific surface area (SSA) decrease.
This showed that the sample with a higher number of cycles exhibits the highest median grain size and surface roughness value, as well as the lowest dislocation density and specific surface area. These results are important in order to identify the optimum layer number needed for the formation of BFO thin films exhibiting an improved SSA, which plays a key role in gas sensing.
Author Contributions
M.B., K.A.B., Y.B. and M.Z. contributed equally to this manuscript. All authors have read and agreed to the published version of the manuscript.
Funding
This research received no external funding.
Institutional Review Board Statement
Not applicable.
Informed Consent Statement
Not applicable.
Data Availability Statement
No new data were created or analyzed in this study. Data sharing is not applicable to this article.
Conflicts of Interest
The authors declare no conflict of interest.
References
- Jayanthi, G.; Sumathi, S.; Kannan, K.; Andal, V.; Murugan, S. A Review on Synthesis, Properties, and Environmental Application of Fe-Based Perovskite. Adv. Mater. Sci. Eng. 2022, 2022, 6607683. [Google Scholar] [CrossRef]
- Wang, N.; Luo, X.; Han, L.; Zhang, Z.; Zhang, R.; Olin, H.; Yang, Y. Structure, Performance, and Application of BiFeO3 Nanomaterials. Nano-Micro Lett. 2020, 12, 81. [Google Scholar] [CrossRef]
Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content. |
© 2024 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).