2021 Fiscal Year Annual Research Report
Platform for atomic-order thermal probing and elucidation of wave-like heat conduction
| Project/Area Number |
20H02090
|
|---|
| Research Institution | Kyushu University |
|---|
Principal Investigator |
李 秦宜 九州大学, 工学研究院, 准教授 (60792041)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
高橋 厚史 九州大学, 工学研究院, 教授 (10243924)
|
|---|
| Project Period (FY) |
2020-04-01 – 2023-03-31
|
| Keywords | Nanoscale heat transfer / Thermal conductivity |
|---|
| Outline of Annual Research Achievements |
In FY2021, we have first established an experimental method that allows concurrently the in-situ thermal conductivity measurement and the real-time internal structure observation of a single one-dimensional (1D) material using scanning transmission electron microscopy in a scanning electron microscope (STEM-in-SEM). Using this method, we in-situ measured the thermal conductivities of individual cup-stacked carbon nanotubes and concurrently observed the internal hollow structures. We found that the sample with more structural disorders had a lower thermal conductivity. Our measurement method can pave the way to the sample by-sample elucidation of the structure-property relationship for 1D materials. This achievement has been published in Appl. Phys. Lett. Second, we have established the method to tune the thermoelectric properties of monolayer graphene by introducing gate voltage. Third, we have tested how to introduce nanoscale defects in graphene with a nano-probe and measured the temperature distribution with scanning thermal microscopy (SThM) at the same time. We have analyzed the heat transfer mechanisms and errors related with the contact SThM thermometry. Fourth, we have prepared nanoscale samples for lock-in Raman measurements. Besides, we have developed a method to measure nanoscale flow characteristics in graphene nanochannels.
|
| Current Status of Research Progress |
Current Status of Research Progress
2: Research has progressed on the whole more than it was originally planned.
Reason
This project aims to develop a platform for nanoscale thermophysical property measurement and elucidate nanoscale heat transfer mechanisms. In FY2021, in addition to the establishment of the Raman-based platform, we have set up the platform based on electron microscopy and scanning thermal microscopy. We also elucidated the relationship between the internal nanostructure and the thermal conductivity of individual 1D materials.
|
| Strategy for Future Research Activity |
In FY2022, we will first apply the lock-in Raman technique in the thermal conductivity mapping of individual low-dimensional materials. Second, we will optimize the platform based on electron microscopy and use this platform to study a variety of nanoscale heat conduction phenomena.
|
