Temperature Calibration for In Situ Environmental Transmission Electron Microscopy Experiments

Area of Science:

• Materials Science
• Nanotechnology
• Physical Chemistry

Background:

• In situ environmental transmission electron microscopy (ETEM) requires precise temperature control for studying material behavior under gaseous conditions.
• Accurate measurement of local sample temperature is vital for determining kinetic parameters like activation energies, especially when temperature fluctuates due to gas introduction.

Purpose of the Study:

• To develop and validate a method for accurate local sample temperature measurement in ETEM.
• To calibrate the local sample temperature using silver nanoparticles and selected-area diffraction (SAD).

Main Methods:

• Utilized in situ environmental transmission electron microscopy (ETEM).
• Employed selected-area diffraction (SAD) to measure the lattice parameter of silver (Ag) nanoparticles.
• Correlated Ag lattice expansion with temperature and hydrogen gas pressure to calibrate local sample temperature.

Main Results:

• Established a calibration method for local sample temperature measurement in ETEM using Ag nanoparticles.
• Achieved temperature measurement accuracy of ±30°C via SAD and Ag lattice expansion.
• Quantified significant sample cooling (several hundred degrees Celsius) upon introduction of hydrogen gas at achievable ETEM pressures.

Conclusions:

• Selected-area diffraction (SAD) provides a reliable method for in situ temperature calibration in ETEM.
• Gas introduction in ETEM can induce substantial, previously underestimated, sample cooling.
• Accurate temperature measurement is critical for reliable kinetic studies in gaseous environments using ETEM.