Related Experiment Video
Updated: Mar 17, 2026
13:29
Harvesting Solar Energy by Means of Charge-Separating Nanocrystals and Their Solids
Published on: August 23, 2012
14.8K
Large-scale cauliflower-shaped hierarchical copper nanostructures for efficient photothermal conversion
Peixun Fan1, Hui Wu, Minlin Zhong
1Laser Materials Processing Research Centre, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, PR China. fpx@tsinghua.edu.cn zhml@tsinghua.edu.cn.
Nanoscale
|July 20, 2016
Summary
Researchers developed a laser-textured copper surface with cauliflower-like nanostructures for efficient solar energy harvesting. This broadband, omnidirectional absorber achieves high photothermal conversion efficiency, promising for various applications.
Area of Science:
- Materials Science
- Nanotechnology
- Renewable Energy
Background:
- Efficient solar energy harvesting and photothermal conversion are critical for numerous applications.
- Developing advanced materials with high light absorption capabilities is essential for improving solar energy technologies.
Purpose of the Study:
- To present a novel laser-induced hierarchical nanostructure on a copper surface.
- To investigate the light absorption and photothermal conversion properties of the nanostructured surface.
Main Methods:
- Fabrication of a cauliflower-shaped hierarchical surface nanostructure on copper using femtosecond laser writing.
- Measurement of hemispherical absorptance and angle-dependent specular reflectance across a broad spectral range (UV to near-infrared).
- Evaluation of photothermal conversion efficiency through a water evaporation experiment under simulated solar illumination.
Main Results:
- The nanostructured copper surface demonstrated extremely high omnidirectional absorption efficiency (average hemispherical absorptance of 98% from 200-800 nm).
- Specular reflectance remained below 0.1% for incident angles up to 60°.
- An overall photothermal conversion efficiency exceeding 60% was achieved under solar illumination (∼1 kW m⁻²).
Conclusions:
- The laser-induced nanostructure offers a cost-effective, reliable, and scalable method for creating broadband, omnidirectional light-absorptive metal surfaces.
- This technology holds significant potential for applications in solar energy harvesting, anti-reflection coatings, and photothermal conversion.
- The femtosecond laser writing technique is suitable for mass production and large-area applications.
