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Electromagnetic-Thermal Coupling Competition in Ag@TiO2 Core-Shell Nanorods Under Distance-Dependent Interaction
Bojun Pu1, Paerhatijiang Tuersun1, Jingxian Wang1
1Xinjiang Key Laboratory of Luminescence Minerals and Optical Functional Materials, School of Physics and Electronic Engineering, Xinjiang Normal University, Urumqi 830054, China.
Nanomaterials (Basel, Switzerland)
|July 27, 2026
Summary
The photothermal response of silver-titanium dioxide (Ag@TiO2) core-shell nanorods depends non-monotonically on particle spacing. Near-field coupling and thermal effects compete, influencing heat accumulation and optical properties for plasmonic nanomaterials.
Area of Science:
- Nanomaterials Science
- Plasmonics
- Photothermal Therapy
Background:
- Plasmonic nanomaterials exhibit significant photothermal responses.
- Inter-particle electromagnetic and thermal interactions critically influence this response.
Purpose of the Study:
- Investigate the distance-dependent photothermal behavior of Ag@TiO2 core-shell nanorods.
- Analyze the interplay between electromagnetic and thermal fields in coupled nanorod systems.
Main Methods:
- Finite element method (FEM) simulations.
- Modeling of single and dual Ag@TiO2 core-shell nanorod systems.
- Analysis of optical absorption and temperature distribution under 808 nm laser irradiation.
Main Results:
- Reduced inter-particle distance leads to competing effects: enhanced heat accumulation via thermal-field superposition and weakened heat generation due to plasmonic coupling.
- Plasmonic coupling at small separations shifts resonance and reduces effective absorption cross-section.
- Photothermal response shows non-monotonic dependence on inter-particle distance.
Conclusions:
- Clarified the electromagnetic-thermal coupling mechanism in Ag@TiO2 core-shell nanorods.
- Provided a theoretical framework for understanding distance-dependent photothermal effects in plasmonic nanostructures.
- Offers insights for designing nanomaterials for applications sensitive to particle arrangement.
Keywords:
core-shell nanoparticlesfinite element methodlocalized surface plasmon resonancephotothermal coupling effectphotothermal field distributionMore Related Videos
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