3D Interconnected Gyroid Au-CuS Materials for Efficient Solar Steam Generation

Surface plasmon resonance (SPR), a promising technology, is beneficial for various applications, such as photothermal conversion, solar cells, photocatalysts, and sensing. However, the SPR performance may be restricted by the 1D- or 2D-distributed hotspots. The bicontinuous interconnected gyroid-structured materials have emerged in light energy conversion due to a high density of 3D-distributed hotspots, ultrahigh light-matter interactions and large scattering cross-section. Here, a series of bioinspired Au-CuS gyroid-structured materials are fabricated by precisely controlling the deposition time of CuS nanoparticles (NPs) and then adopted for solar steam generation. Specifically, Au-CuS/GMs-80 present the highest evaporation efficiency of 88.8% under normal 1 sun, with a suitable filling rate (57%) and a large inner surface area (∼2.72 × 10⁵ nm² per unit cell), which simultaneously achieves a dynamic balance between water absorption and evaporation as well as efficient heat conduction with water in nanochannels. Compared with other state-of-the-art devices, Au-CuS/GMs-80 steam generator requires a much lower photothermal component loading (<1 mg cm^-2) and still guarantees outstanding evaporation performance. This superior evaporation performance is attributed to broadband light absorption, continuous water supply, excellent heat generation and thermal insulation, and good light-heat-water interaction. The combination of 3D interconnected nanostructures with controllable metal-semiconductor deposition could provide a new method for the future design of high-performance plasmonic devices.