A confocal-controlled Raman-LIBS hybrid microscope with high stability and spatial resolution

• Published in: Journal of analytical atomic spectrometry Vol. 38; no. 4; pp. 792 - 799
• Main Authors: Zhao, Weiqian, He, Chunjing, Li, Angze, Qiu, Lirong, Xu, Ke-Mi
• Format: Journal Article
• Language: English
• Published: London Royal Society of Chemistry 05.04.2023
• Subjects: Banded structure; Drift; High resolution; Hybrid systems; Laser ablation; Meteorites; Meteors & meteorites; Minerals; Space exploration; Spatial resolution; Structural analysis
• ISSN: 0267-9477; 1364-5544
• DOI: 10.1039/d2ja00360k

Probing elemental and molecular structural information with a high spatial resolution is a key bottleneck in determining unknown minerals in the fields of geology and space exploration. An untraditional confocal-controlled Raman-LIBS hybrid method with high spatial resolution and anti-drift properties has been developed to overcome this challenge. The method is the first to combine Rayleigh/reflected light, LIBS signal, and Raman spectrum to simultaneously measure geometrical topography and elemental and molecular structural information. The hybrid system utilizes real-time focus tracking the performance of Rayleigh/reflected light to achieve accurate spectral measurements. The axial-focusing resolution and lateral resolution for morphological imaging are improved to ∼15 nm and 600 nm, which improves the anti-drift capability and minimizes the laser ablation size, thereby achieving a high transverse resolution of ∼9 μm, and a high axial resolution of ∼10 μm. As a proof of concept, high-resolution topological and hybrid spectral maps of the Northwest Africa 13323 meteorite have been measured. The fusion of the LIBS and Raman data provides a detailed three-dimensional map of the elementary and compositional distributions of the meteorite. Further analysis of the D and G bands in the Raman map reveals structural information reflecting the thermal metamorphism of the meteorite. The proposed Raman-LIBS hybrid microscope provides valuable information for composition and structure analysis, and it is a powerful tool for studying unknown minerals in the fields of geology and space exploration. A novel confocal controlled Raman-LIBS hybrid microscope, with a high spatial resolution and antidrift property, has been developed. The microscope provides valuable compositional and structural analysis and is a powerful tool to study unknown minerals.