Sample interview questions: Describe the principles behind laser-induced breakdown spectroscopy and its applications in environmental monitoring.
Sample answer:
Laser-induced Breakdown Spectroscopy (LIBS): Principles and Environmental Monitoring Applications
1. LIBS Mechanism:
- When a high-power laser is focused on a material, it generates a plasma plume due to the absorption of laser energy by the sample’s atoms.
- This plasma formation involves the ejection of atoms, ions, and electrons from the sample into an excited state.
- The excited species then emit light at specific wavelengths corresponding to their atomic or molecular structure.
- The intensity of emitted light is proportional to the concentration of the elements present in the sample.
2. Advantages of LIBS for Environmental Monitoring:
- Rapid and Real-time Analysis: LIBS provides rapid and real-time analysis of various elements and compounds present in a sample.
- Minimal Sample Preparation: LIBS requires minimal or no sample preparation, making it a convenient technique for field measurements.
- Remote Sensing Capability: LIBS can be used for remote sensing of elements, allowing for the analysis of hazardous or inaccessible environments.
- Cost-effective and Portable: LIBS instrumentation is relatively cost-effective compared to other analytical techniques and can be made portable for field deployment.
3. LIBS Applications in Environmental Monitoring:
- Soil Analysis: LIBS helps in determining the elemental composit… Read full answer