Knudsen effusion mass spectrometry: Current and future approaches

Area of Science:

• Physical Chemistry
• Materials Science
• Analytical Chemistry

Background:

• Knudsen effusion mass spectrometry (KEMS) has been a foundational technique in physical chemistry since 1954.
• Existing literature provides comprehensive reviews of KEMS basic principles.
• This review focuses on the contemporary status and future potential of KEMS.

Purpose of the Study:

• To review the current state of Knudsen effusion mass spectrometry (KEMS).
• To explore potential growth areas and novel applications of KEMS.
• To discuss advancements in KEMS instrumentation and measurement techniques.

Main Methods:

• Discussion of KEMS instrumentation, including improved heating and temperature measurement for better Knudsen cell control.
• Analysis of measurement techniques, incorporating accurate computer models for effusive beam optimization and ionizer sensitivity.
• Examination of advanced data acquisition systems for enhanced data quantity and quality.

Main Results:

• KEMS is traditionally used for thermodynamic measurements of compounds and solutions, now enhanced by computational thermochemistry.
• First principles calculations aid in determining Gibbs energy functions and comparing ab initio results with KEMS measurements.
• KEMS applications extend to phase changes, low-oxygen systems, ultrahigh-temperature ceramics, geology, nuclear science, organic compounds, and functional materials like lithium-ion batteries.

Conclusions:

• KEMS instrumentation and measurement methodologies are continually improving.
• Selected KEMS studies showcase promising future research directions.
• The review provides an overview of KEMS's current capabilities and future prospects.