THE CHALLENGE
A major business challenge in advancing solar thermal technologies lies in developing cost-effective, durable coatings that can withstand extreme heat while maximizing efficiency. Current solar absorber materials—like traditional black oxides or multi-layer coatings—often fall short due to high infrared heat loss, poor durability under repeated thermal cycling, and expensive, complex manufacturing methods. Techniques such as nano- or micro-texturing can improve light absorption but require multi-step fabrication processes that drive up production costs and limit scalability, especially on large or curved surfaces. While electrodeposition offers a cheaper and scalable route, it typically produces smooth films with poor light-trapping capability. Without a simple, robust, and affordable way to create coatings that absorb nearly all sunlight and emit minimal heat, solar thermal systems remain too costly for widespread commercial use, limiting their potential to compete with conventional energy sources.
OUR SOLUTION
We offer a simple, scalable, and cost-effective method to produce high-performance solar-absorbing coatings that can withstand extreme temperatures and harsh conditions. Using a one-step electrodeposition process followed by low-temperature annealing, we create durable, fractal-textured surfaces that absorb over 90% of sunlight while minimizing heat loss, achieving solar-to-heat conversion efficiencies as high as 99%. Unlike traditional methods that require expensive multi-step patterning or fragile multilayer films, our approach uses readily available metals to form nano- to micro-scale structures directly on industrial substrates such as stainless steel or Inconel. This eliminates the need for complex equipment, reduces manufacturing costs, and enables large-area or curved-surface coating. The resulting coatings maintain performance after repeated thermal cycling, water exposure, and mechanical wear, making them ideally suited for commercial-scale solar thermal applications, such as power generation, industrial heating, and desalination—helping to lower the levelized cost of renewable energy.
Figure: Solar receiver tube schematic and SEM showing multiscale fractal textures of electrodeposited absorber for efficient solar absorption.
Advantages:
- Ultra-high solar-to-heat efficiency (up to 99%)
- Exceptional thermal and environmental stability (up to 750 °C, long-term durability)
- Low-cost, scalable one-step fabrication via ambient-condition electrodeposition
- Intrinsic light-trapping fractal textures eliminate need for antireflective coatings
Potential Application:
- Concentrated solar power (CSP) systems
- Industrial high-temperature process heat
- Thermochemical fuel production
- Solar desalination and water heating
