Green Synthesis and Characterization of Manganese Oxide Nanostructures by PL Spectroscopy
Board Location: #147
Discipline: Nanoscience or Materials Science
Session: 3
Naomy K Fontanez Rosa - Inter American University of Puerto Rico Bayamon Campus
Co-Author(s): Pedro Hidalgo, Complutense University of Madrid, Madrid Spain Dorcas Torres, Inter American University of Puerto Rico Bayamon Campus, Bayamon Puerto Rico
Green Synthesis and Characterization of Manganese Oxide Nanostructures by PL Spectroscopy
N. Fontanez1, P. Hidalgo2, and D. I. Torres1*
1Natural Science and Mathematics Department, Inter American University of Puerto Rico, Bayamon Campus
2Material Physics Department, Physic Faculty, Complutense University of Madrid, Spain
Photoluminescence (PL) is a sensitive tool for detecting deviations in atomic configurations and defects, even at low concentrations. PL spectroscopy helps determine the electronic structure and properties of materials and is widely used to characterize the optoelectronic properties of semiconductors. The advantages of fluorescence analysis are high sensitivity, strong selectivity, small sample volume, more physical parameters, and ease of use. Typical applications include band gap determination, impurity levels and defect detection, recombination mechanisms, material quality, and molecular structure and crystallinity.
Nanoparticles (NPs) exhibit unique optical, electronic, mechanical, and magnetic properties compared with their bulk materials. Several physiochemical techniques are common choices for the synthesis of nanoparticles, such as vapor phase growth, sol-gel, and thermal reflux. However, these methods involve toxic chemicals, which may create hazardous effects in biomedical applications. Instead, green synthesis has emerged as highly efficient, environmentally friendly, non-toxic, and low-cost. Manganese oxide NPs have attracted the attention of researchers due to their extensive physical and chemical properties, which offer a wide range of applications such as catalysis, ion exchange, molecular adsorption, energy storage, and chemical and biological sensing.
This work reported plant extract-based syntheses of manganese oxide nanostructures using potassium permanganate (KMnO2) as a precursor. Plant extracts of lemon peel (Citrus limon), ginger (Zingiber officinale), and the moriviví leaf (Mimosa pudica) were used as a reducing agent. The precipitate obtained was calcinated for 3 hours at 700 °C. We investigated the influence of the natural extracts on the emission (EM) spectra of the nanostructures formed. Scanning Electron Microscopy (SEM) and Raman spectroscopy were used as complementary characterization techniques for morphologies and crystalline structures.
The results indicate that the EM spectra and the size and morphology of the nanostructures produced are dependent on plant extract. PL emission indicated two coexistent type structures: Mn(II) complex in a tetrahedral environment and -MnO2. The Raman results confirm the above, demonstrating the high sensitivity of the PL technique.
Funder Acknowledgement(s): Pedro Hidalgo, Dorcas I. Torres
Faculty Advisor: Dorcas I. Torres, ditorres@bayamon.inter.edu
Role: I have been working on the synthesis of the nanoparticles used in the research. I have also been taking SEM and Raman measurements at the Complutense University of Madrid, and I have been involved in every part of the research analysis.