Quantitative Analysis of Fluorine by EDXRF: Powder and Fluorine-Containing Fil

Significance of the Topic

Fluorine-containing compounds are critical in many industries for their flame retardancy, water repellence, antifouling behavior and thermal stability. Accurate quantification of fluorine in diverse sample forms—solids, powders and thin films—is essential for quality control in manufacturing, materials research and regulatory compliance. Energy dispersive X-ray fluorescence (EDXRF) offers a direct, non-destructive approach, reducing sample preparation time compared to ion chromatography or SEM-EDS methods.

Objectives and Study Overview

The study presents two case examples using the Shimadzu EDX-8000/8100 spectrometer for fluorine analysis:

• Quantitative determination of fluorine in powder samples across a range of concentrations.
• Measurement of fluororesin (PTFE) coating weight on glass substrates using a film fundamental parameter method.

Methodology and Instrumentation

Powder analysis involved preparing briquettes of cellulose mixed with lithium fluoride standards (0, 2 500, 5 000 ppm F). Coating film samples were generated by spraying PTFE onto glass plates at three different thicknesses. Key measurement conditions:

• Instrument: Shimadzu EDX-8000/8100
• Detector: Silicon drift detector (SDD)
• X-ray tube: Rhodium target, 15 kV
• Atmosphere: Vacuum
• Integral time: 300 s
• Quantitation methods: Calibration curve and film fundamental parameter (FP)

Main Results and Discussion

For powder samples, the calibration curve demonstrated linearity down to 55 ppm accuracy, with a theoretical detection limit of 203 ppm. Repeatability on the 5 000 ppm standard yielded a coefficient of variation of 2.5 %.
Coating weight analysis achieved a detection limit of 0.13 µg/cm2. Measured weights for three PTFE samples ranged from 10.4 to 127.5 µg/cm2, with repeatability CV below 0.4 %.
Overlay profiles of FKα peaks confirmed consistent qualitative detection across standards and samples.

Benefits and Practical Applications

• Minimal sample preparation: Direct analysis of powders, solids and films without dissolution or cutting.
• Non-destructive: Samples remain intact for subsequent testing.
• High sensitivity: Quantitation of fluorine at sub-percent levels in diverse matrices.
• User-friendly operation: Simple measurement workflow suitable for users with limited experience.

Future Trends and Opportunities

Advancements in detector technology and software algorithms could further lower detection limits for light elements. Integration of automated sample handling and real-time data processing will streamline high-throughput screening in industrial settings. Expanded application of EDXRF in environmental monitoring, polymer research and semiconductor manufacturing is anticipated, driven by demand for rapid, reliable elemental analysis.

Conclusion

The Shimadzu EDX-8000/8100 spectrometer effectively quantifies fluorine in powders and thin films without chemical pretreatment. It delivers reliable detection at low concentrations, high precision and rapid, non-destructive analysis, making it a valuable tool for quality control and research applications in materials science and related fields.