Vibrational Profiling of La:ZnO–Graphene Micropowders
Cristina Ionela Pachiu1, Dumitru Manica1, Andreea Gabriela Marina Popescu1, Roxana Marinescu1, Cosmin Romanitan1, Oana Brincoveanu1, Emmanouel Koudoumas1,2 and Mirela Petruta Suchea1,2
1 National Institute for Research and Development in Microtechnologies—IMT Bucharest, 126A, Erou Iancu Nicolae Street, 077190 Voluntari-Bucharest, Romania;
2 Center of Materials Technology and Photonics (CEMATEP), School of Engineering and Research and Innovation Center (PEK), Hellenic Mediterranean University (HMU), 71410 Heraklion, Crete, Greece
Abstract
This study explores hierarchically organized La-doped ZnO–graphene nanostructured micropowders synthesized through an electrospinning–calcination route. Unlike traditional hydrothermal methods that yield simple nanoparticle-on-sheet structures, this approach produces complex micro-assemblies of rod-like, flower-like, and nanoparticulate elements interconnected by graphene nanoplatelet veils. While X-ray diffraction confirms the stability of the hexagonal wurtzite ZnO lattice across varying graphene concentrations, Raman spectroscopy and mapping reveal significant local vibrational heterogeneity. Graphene acts as an active modulator of the interfacial environment, with concentration-dependent shifts in the D, G, and 2D bands appearing alongside characteristic ZnO phonons. These results highlight the importance of multiscale structural organization and graphene loading in tuning the local vibrational response of La:ZnO hybrids, providing a foundation for developing advanced composite materials tailored for sensing, optoelectronic, and electromagnetic applications.
Keywords: Raman Structural characterisation; La/ZnO/graphene nanocomposites.
Acknowledgments: IMT’s contribution was partially supported by the Romanian Ministry of Research, Innovation and Digitalisation through the μNanoEl, Cod: 23 07 core Programme and partially supported by PNRR/2022/C9/MCID/I8 CF23/14/11.2022 contract 760101/23.05.2023 financed by the Ministry of Research, Innovation and Digitalization, project “Development of a program to attract highly specialized human resources from abroad in research, development, and innovation activities”.
References
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