Plasmonic nanoparticle-embedded poly(p-phenylene benzobisoxazole) nanofibrous composite films for solar steam generation.

High-performance floating film-based solar steam generation has received extensive attention for clean fresh water generation. Herein, we report high-strength nanoporous gold nanoparticle (AuNP)/poly(p-phenylene benzobisoxazole) nanofibre (PBONF) composite films that are capable of enhanced solar steam generation. The PBONFs were employed as building blocks to fabricate nanoporous PBONF multilayer composite films using a layer-by-layer assembly technique. These PBONF multilayer composite films then served as supports for depositing AuNPs. The resulting AuNP/PBONF composite films exhibit a high strength of 122 MPa and Young's modulus of 3.7 GPa, a broad spectrum photothermal effect, a mesoscopic structure, and a low thermal conductivity of 0.230 W m-1 K-1. Under one sun exposure, the AuNP/PBONF composite films exhibit an evaporation rate of 1.424 kg m-2 h-1 and a solar-vapor conversion efficiency of 83%. The AuNP/PBONF composite films are stable; therefore, they can be readily reused. These high-performance AuNP/PBONF composite films have potential for clean water generation under some extreme conditions such as space environments.