Finding a Sensitive Surface-Enhanced Raman Spectroscopic Thermometer at the Nanoscale by Examining the Functional...

Area of Science:

• Nanoscale science
• Spectroscopy
• Physical chemistry

Background:

• Temperature variations at the nanoscale are critical for thermodynamics and kinetics.
• Surface-enhanced Raman spectroscopy (SERS) shows potential for nanoscale temperature monitoring.
• Designing sensitive SERS thermometers remains an ambiguous challenge.

Purpose of the Study:

• To elucidate methods for designing highly sensitive SERS thermometers.
• To investigate the influence of molecular probe chemical bonds and substrate interactions on thermometer sensitivity.
• To provide guidelines for optimizing SERS thermometer design.

Main Methods:

• Variable-temperature SERS measurements were performed on various molecular probes.
• Quantum chemistry calculations were used to determine frequency-temperature functions.
• Analysis focused on the relationship between bond type, surface bonding, and temperature sensitivity.

Main Results:

• The sensitivity of the frequency-temperature function follows the order: triple bond > double bond > single bond.
• This sensitivity trend was observed for both aliphatic and aromatic molecules.
• Surface chemical bonding between the SERS substrate and molecular probe significantly enhances sensitivity.

Conclusions:

• Molecular probe bond type and surface chemical bonding are key factors in SERS thermometer sensitivity.
• Rational design of sensitive SERS thermometers can be achieved by analyzing molecular probe functional groups.
• The findings offer universally applicable guidelines for developing advanced nanoscale temperature sensors.