Ga filled nanothermometers with high sensitivity and wide measuring range

Area of Science:

• Materials Science
• Nanotechnology
• Physical Chemistry

Background:

• Accurate temperature measurement at the nanoscale is crucial for understanding various microphysical and chemical processes.
• Existing nanothermometry methods often face limitations in sensitivity, range, or applicability in diverse microenvironments.
• Gallium (Ga) exhibits unique thermal expansion properties suitable for thermometry applications.

Purpose of the Study:

• To develop and characterize novel gallium-filled nanotube nanothermometers.
• To evaluate the temperature-sensing capabilities of magnesium oxide (MgO) and silica nanotubes filled with gallium.
• To assess the sensitivity and temperature range of these nanothermometers for potential microenvironment applications.

Main Methods:

• Fabrication of gallium-filled MgO and silica nanotubes using a one-step method.
• In situ heating and cooling experiments within a transmission electron microscope (TEM).
• Measurement of gallium column height changes as a function of temperature.

Main Results:

• Both Ga-filled MgO and silica nanotubes demonstrated a linear and reproducible relationship between gallium column height and temperature.
• The Ga-filled MgO nanothermometer exhibited high sensitivity (6.02 nm/°C) within the 30-450 °C range.
• The Ga-filled silica nanothermometer showed moderate sensitivity (1.15 nm/°C) over a broader temperature range (30-900 °C).

Conclusions:

• Gallium-filled nanotubes are effective nanothermometers with tunable sensitivity and temperature range.
• The Ga-filled MgO nanothermometer is among the most sensitive nanothermometers reported to date.
• These nanothermometers offer a promising solution for temperature monitoring in various microenvironments.