Understanding and Controlling Photothermal Responses in MXenes
Burak Guzelturk1, Vladislav Kamysbayev2, Di Wang2
1X-ray Science Division, Argonne National Laboratory, Lemont, Illinois 60439, United States.
Nano Letters
|March 14, 2023
Summary
MXenes exhibit strong electron-phonon coupling for rapid light-to-heat conversion. Controlling flake size or surface termination enhances thermal boundary conductance, optimizing heat dissipation for photothermal applications.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- MXenes offer potential for efficient light-to-heat conversion.
- Understanding nonequilibrium processes like electron-phonon coupling is crucial for photothermal applications.
Purpose of the Study:
- Investigate ultrafast heating and cooling dynamics in photoexcited MXenes.
- Elucidate the role of electron-phonon and phonon-phonon couplings.
- Optimize heat dissipation for enhanced photothermal and thermoelectric applications.
Main Methods:
- Utilized transient electron and X-ray diffraction.
- Studied MXenes with varying film thicknesses, surface terminations, flake sizes, and annealing conditions.
- Analyzed thermal relaxation governed by thermal boundary conductance (TBC).
Main Results:
- Observed extremely strong electron-phonon coupling in Ti3C2-based MXenes, leading to rapid lattice heating (hundreds of femtoseconds).
- Identified TBC as the key factor in thermal relaxation for thin films.
- Achieved a 2-fold enhancement in TBC (up to 20 MW m-2 K-1) by manipulating flake size and surface termination.
Conclusions:
- Strong electron-phonon coupling in MXenes facilitates efficient photothermal energy conversion.
- Engineering TBC through material design is a viable strategy for optimizing heat dissipation.
- Enhanced TBC in MXenes holds promise for advanced photothermal and thermoelectric devices.
Keywords:
MXenesTi3C2Txphotothermal propertiestime-resolved X-ray scatteringultrafast electron diffractionMore Related Videos
Related Concept Videos
01:26Thermal and Photochemical Electrocyclic Reactions: Overview
2.4K
Electrocyclic reactions are reversible reactions. They involve an intramolecular cyclization or ring-opening of a conjugated polyene. Shown below are two examples of electrocyclic reactions. In the first reaction, the formation of the cyclic product is favored. In contrast, in the second reaction, ring-opening is favored due to the high ring strain associated with cyclobutene formation.
2.4K
01:16Thermal Sigmatropic Reactions: Overview
2.1K
Sigmatropic rearrangements are a class of pericyclic reactions in which a σ bond migrates from one part of a π system to another. These are intramolecular rearrangements where the total number of σ and π bonds remain unchanged.
Sigmatropic shifts are classified based on an order term [i, j ], where i and j indicate the number of atoms across which each end of the σ bond migrates. Below are examples of a [3,3] sigmatropic shift in...
Sigmatropic shifts are classified based on an order term [i, j ], where i and j indicate the number of atoms across which each end of the σ bond migrates. Below are examples of a [3,3] sigmatropic shift in...
2.1K
01:23Electrophilic Addition of HX to 1,3-Butadiene: Thermodynamic vs Kinetic Control
2.7K
The addition of a hydrogen halide to 1,3-butadiene gives a mixture of 1,2- and 1,4-adducts. Since more substituted alkenes are more stable, the 1,4-adduct is expected to be the major product. However, the product distribution is strongly influenced by temperature; low temperature favors the 1,2-adduct, whereas the 1,4-adduct is predominant at high temperature.
2.7K