Thermal Conductivity and Nonlinear Temperature Dependent Raman Line-Shape Asymmetry in Spinel Co3O4: Inhomogeneous Laser Heating Revisited

Abstract

Inhomogeneous laser heating has been revisited here in nanocrystalline Co3O4 by means of laser flux dependent Raman scattering experiments. The exploration of microscopic phenomena in nanoscale semiconductors is pivotal for their integration into various industrial applications. Notably, the presence of laser heating effects in such systems serves as a crucial tool for investigating the quantum properties of materials. The evolution of asymmetric Raman line-shapes with increasing laser flux reveals an entirely distinct behavior of the A1g Raman band in Co3O4 nanoparticles compared to their microcrystalline and bulk counterparts. This phenomenon has been further substantiated through the estimation of the local temperature rise and the corresponding thermal conductivity across three different dimensions of Co3O4. These findings offer profound insight into the thermal and quantum dynamics of nanostructured materials. © 2025 American Chemical Society.