Structure‐Interface Synergistic Cu–Zn Hybrid Films for High‐Efficiency Thermal Management and Photothermal Conversion

Why It Matters

The ability to convert sunlight to heat rapidly while maintaining high thermal conductivity enables more efficient solar thermal collectors and photothermal devices, reducing material usage and cost. This breakthrough could accelerate deployment of renewable‑energy technologies that rely on compact, high‑performance heat management.

Key Takeaways

• Structured Cu–Zn interfaces reduce thermal resistance.
• 8 vol% loading yields 2.73 W/m·K in‑plane conductivity.
• Broadband absorption spans 200–800 nm spectrum.
• Film reaches 91.3 °C in 30 s under UV.
• Scalable electrodeposition enables mass production.

Pulse Analysis

Photothermal conversion sits at the heart of solar‑thermal power, water purification, and on‑demand heating, yet conventional materials often force a trade‑off between light capture and heat conduction. Nanoscale plasmonic fillers excel at harvesting photons but suffer from poor dispersibility and high interfacial thermal resistance, while micrometer‑scale metal particles conduct heat efficiently but reflect much of the incident spectrum. Bridging this gap requires a design that simultaneously maximizes broadband absorption and creates low‑resistance pathways for the generated heat, a challenge that has limited the efficiency of many commercial systems.

The newly reported Cu–Zn hybrid film tackles this dilemma through a multiscale interface strategy. By electrodepositing Zn onto the edges of Cu flakes, researchers generate bead‑chain‑like nanostructures that act as plasmonic antennas while forming a metallic backbone that stitches individual flakes together. At a modest 8 vol% loading, the composite achieves an in‑plane thermal conductivity of 2.73 W m⁻¹ K⁻¹ and a through‑plane value of 1.06 W m⁻¹ K⁻¹, surpassing many pure‑metal fillers. Optical measurements show continuous absorption across 200–800 nm, and under 365 nm UV light the film reaches 91.3 °C in just 30 seconds, demonstrating rapid and stable photothermal performance.

Beyond laboratory metrics, the Cu–Zn approach offers a clear path to scalable manufacturing. Electrodeposition and alloying are already established in metal‑coating industries, allowing the process to be adapted for roll‑to‑roll production of large‑area films. The resulting material can be integrated into solar collectors, thermophotovoltaic receivers, and self‑heating textiles without sacrificing mechanical flexibility. As the renewable‑energy sector seeks higher power density and lower material footprints, such interface‑engineered composites could become a cornerstone for next‑generation thermal management solutions, driving cost reductions and broader market adoption.