Laser flash-Raman spectroscopy method for the measurement of the thermal properties of micro/nano wires

2015 ◽  
Vol 86 (1) ◽  
pp. 014901 ◽  
Author(s):  
Jinhui Liu ◽  
Haidong Wang ◽  
Yudong Hu ◽  
Weigang Ma ◽  
Xing Zhang
Keyword(s):  
Raman Spectroscopy ◽  
Thermal Properties ◽  
Laser Flash ◽  
Spectroscopy Method ◽  
Nano Wires

Laser Flash Raman Spectroscopy Method for Characterizing Thermal Diffusivity of Suspended and Supported 2D Nanomaterials

2016 ◽  
Author(s):  
Qin-Yi Li ◽  
Xing Zhang
Keyword(s):  
Thermal Conductivity ◽  
Raman Spectroscopy ◽  
Thermal Diffusivity ◽  
Laser Power ◽  
2D Materials ◽  
Laser Flash ◽  
Spectroscopy Method ◽  
Measured Temperature ◽  
Laser Absorption ◽  
2D Nanomaterials

2D nanomaterials have been attracting extensive research interests due to their superior properties and the accurate thermophysical characterization of 2D materials is very important for nanoscience and nanotechnology. Recently, a noncontact technique based on the temperature dependent Raman band shifts has been used to measure the thermal conductivity of 2D materials. However, the heat flux, i.e. the absorbed laser power, was either theoretically estimated or measured by a laser power meter with uncertainty, resulting in large errors in thermal conductivity determination. This paper presents a transient “laser flash Raman spectroscopy” method for measuring the thermal diffusivity of 2D nanomaterials in both the suspended and supported forms without knowing laser absorption. Square pulsed laser instead of continuous laser is used to heat the sample and the laser absorption can be eliminated by comparing the measured temperature rises for different laser heating time and laser spot radii. This method is sensitive for characterizing typical 2D materials and useful for nanoscale heat transfer research.

Laser Flash Raman Spectroscopy Method for Characterizing the Specific Heat of a Single Nanoparticle

2019 ◽  
Vol 19 (11) ◽  
pp. 7004-7013 ◽  
Author(s):  
Aoran Fan ◽  
Qinyi Li ◽  
Weigang Ma ◽  
Xing Zhang
Keyword(s):  
Raman Spectroscopy ◽  
Specific Heat ◽  
Thermophysical Properties ◽  
Laser Flash ◽  
Measurement Methods ◽  
Lumped Parameter Model ◽  
Spectroscopy Method ◽  
Thermal Contact Conductance ◽  
Single Nanoparticle ◽  
Suspended Substrate

Nanoparticles are widely used in composite materials, nanoscale devices, biological detectors and medical treatment. The thermophysical properties of a single nanoparticle are, therefore, important for both nanotechnology and nanoscience applications. However, property measurements are limited by the spatial resolution of conventional measurement methods, so there are not yet any effective measurement methods to characterize the thermophysical properties of a single nanoparticle. This paper describes a laser flash Raman spectroscopy method for measuring the specific heat of a single nanoparticle supported on a free-standing substrate based on a lumped parameter model for the nanoparticle coupled with a transient 2D thermal conduction model for the suspended substrate. A series of square laser pulses are assumed to be used to heat the supported single nanoparticle in a vacuum. The temperature increases in the single nanoparticle and the suspended substrate are then measured based on their Raman band shifts. The laser absorption coefficients of the nanoparticle and the substrate are then eliminated by comparing the temperature increases measured using different laser pulse widths. The specific heat of the nanoparticle and the thermal contact conductance between the nanoparticle and the substrate can then be extracted by fitting the temperatures of both the nanoparticle and the substrate. Case studies show that the method can accurately measure the specific heat of a single nanoparticle about 100 nm in diameter using ~1 ns pulse widths. The influence of the nanoparticle geometry and the thermophysical properties of the substrate are also discussed.

Application of Raman spectroscopy method for analysis of biopolymer materials

2016 ◽  
Author(s):  
Elena V. Timchenko ◽  
Pavel E. Timchenko ◽  
S. E. Volchkov ◽  
Alexsandra O. Mahortova ◽  
Anna A. Asadova ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Spectroscopy Method
Sign in / Sign up

Export Citation Format

Share Document