Dual Janus foam for directional thermal management
Chao Jiang1, Xingmei He1, Xinghua Zheng2,3
1Department of Chemical Engineering, Institute of Polymer Science and Engineering, Tsinghua University, Beijing, China.
Nature Communications
|February 2, 2026
Summary
This study introduces dual Janus foams for advanced directional thermal management, improving thermal energy harvesting by combining photothermal and thermal rectification properties. This dual asymmetry significantly enhances temperature control for energy applications.
Area of Science:
- Materials Science
- Thermal Engineering
- Energy Harvesting
Background:
- Passive radiative cooling and heating strategies typically focus on radiation properties, neglecting thermal conduction.
- Existing directional thermal management methods often lack integrated radiation regulation.
- Thermal rectifying materials are rare and usually not combined with radiative properties.
Purpose of the Study:
- To design dual Janus foams with dual asymmetries for enhanced directional thermal management.
- To investigate the combined effects of photothermal properties and thermal rectification.
- To improve energy harvesting and utilization through advanced thermal control.
Main Methods:
- Fabrication of dual Janus foams with asymmetric photothermal and thermal rectification properties.
- Characterization of photothermal property contrast and thermal rectification ratios.
- Evaluation of temperature difference ratio improvements using single and dual Janus structures.
Main Results:
- The dual Janus foams exhibit high photothermal property contrast.
- An excellent thermal rectification ratio of 122% was achieved.
- The temperature difference ratio improved from 3% (single Janus) to 65% (dual Janus), a 21-fold increase.
Conclusions:
- Dual Janus foams offer a novel approach to directional thermal management.
- Integrating photothermal and thermal rectification properties significantly enhances thermal energy harvesting.
- This work provides a comprehensive strategy for future directional thermal management systems.
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