Ag and Ni doped graphitic carbon nitride coated on wood as a highly porous and efficient photoabsorber in interfacial solar steam generation

A scalable, cost-effective, maintainable, porous, and high-efficient interfacial solar steam generation (ISSG) device is of great importance to address the challenge of water scarcity. The performance of Ag or/and Ni doped g-C3N4 as efficient photothermal materials coated on poplar wood in ISSG of seawater is evaluated. The photothermal conversion efficiency of g-C3N4 as a photothermal material improves by doping it with Ag or Ni due to the surface plasmon resonance effect of these metals. The Ag doped g-C3N4 represents more solar evaporation efficiency with respect to Ni doped g-C3N4 owing to its stronger absorption in visible and infrared regions. The highest evaporation flux of 3.72 kg m−2 h−1 is achieved for the wood coated by Ag doped g-C3N4 under 3 sun. For this photothermal material, the concentration of Na+ of Caspian seawater decreases from 3150.2 to 3.8 mg L−1. The Ag doped g-C3N4/wood evaporator device is exhibited a stable water generation ability in ten evaporation cycles.