The integration of cerium oxide nanoparticles in solid-state random laser development

This study demonstrates that CeO2 nanoparticles are effective scattering centers within a solid-state random laser (RL) composed of a rhodamine 6G-doped polymeric matrix. Introducing these nanoparticles with nanorod geometry has enabled us to achieve distinct intensity thresholds for two different excitation spot sizes, underscoring the critical role of scattering centers in RL action. Furthermore, our findings reveal a linewidth narrowing from 32 to 8 nm, indicating the transition from spontaneous to stimulated emission. A comparative analysis employing two methodologies, direct analysis and spectral decomposition, yielded consistent results across the board. Each methodology confirmed the presence of an intensity threshold and linewidth narrowing exclusively in the CeO2-doped samples, confirming the absence of such phenomena in the undoped matrix. The synthesis of CeO2 nanostructures by hydrothermal route followed by incorporation into the dye-doped polymeric matrix emphasizes the cost-effectiveness and accessibility of our approach. This practical and scalable synthesis process, coupled with the novel application of CeO2 nanoparticles as scattering centers in solid-state RL systems, is a viable alternative to TiO2, the well-known and most-used scatterer centers in RL systems. Such findings contribute to the current field of RL research and open new possibilities for exploring novel CeO2 morphologies to optimize parameters, e.g., reducing the emission intensity threshold. Such reduction is particularly relevant for creating lab-on-chip devices that can be operated with compact and affordable light sources.