Shell thickness-induced thermal dependence: highly sensitive core-shell CdSe/ZnS/POSS-based temperature probes

Area of Science:

• Materials Science
• Nanotechnology
• Chemical Engineering

Background:

• Quantum dots (QDs) are crucial for non-contact temperature monitoring.
• Tuning QD properties is vital for developing advanced sensors.
• Shell thickness influences QD fluorescence and sensing characteristics.

Purpose of the Study:

• To investigate the effect of shell thickness on the temperature-sensing properties of CdSe/ZnS QDs.
• To develop QD-based temperature probe films with modulated sensing characteristics.
• To optimize QD temperature probes for enhanced performance.

Main Methods:

• Fabrication of CdSe/ZnS QD/POSS films with varying ZnS shell thicknesses.
• Characterization of fluorescence properties and temperature dependency.
• Evaluation of temperature sensitivity, linearity, range, and reversibility.

Main Results:

• ZnS shell thickness significantly regulated temperature dependency, linearity, application range, and reversibility.
• CdSe/ZnS QDs with a 4-monolayer shell exhibited superior thermal stability and a wide usable temperature range (20-80 °C).
• The optimized QD probe achieved excellent temperature sensitivity (R² > 0.994).

Conclusions:

• Shell thickness is a critical factor in optimizing QD temperature sensing performance.
• Controlling QD shell thickness offers a viable strategy for designing high-performance temperature probes.
• This work highlights the potential of shell engineering for advanced QD-based sensing applications.