RGOs-AgNPs/PVA composite sponges for efficient solar saltwater evaporation

• Published in: Diamond and related materials Vol. 145; p. 111099
• Main Authors: Liu, Yuanyuan, Yang, Zhaohua, Lao, Yongjie, Fu, Huili, Zhang, Qiao, Du, Feipeng, Zhang, Yunfei
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.05.2024
• Subjects: PVA sponge; Reduced graphene oxide nanosheets; Silver nanoparticles; Solar evaporation; Synergistic enhancement; Solar evaporation; Synergistic enhancement; Reduced graphene oxide nanosheets; Silver nanoparticles; PVA sponge
• ISSN: 0925-9635; 1879-0062
• DOI: 10.1016/j.diamond.2024.111099

With an increasing demand for seawater desalination, fabricating photothermal materials with low cost, high photothermal conversion efficiency, and excellent mechanical stability is necessary but remains challenging. In this work, reduced graphene oxide nanosheets (RGOs) and silver nanoparticles (AgNPs) doped polyvinyl alcohol (PVA) sponges (RGOs-AgNPs/PVA) are fabricated by the mechanical foaming and impregnation reduction method, which combine the flexible porous structure of PVA sponges with the photothermal properties of RGOs-AgNPs. The incorporation of RGOs-AgNPs enhances the surficial hydrophobicity and reduces the accumulation of water on the surface, and the photothermal synergistic effect of RGOs-AgNPs enhances the water evaporation rate. The results showed that the evaporation rate of RGOs-AgNPs/PVA was 2.09 kg m−2 h−1 and the photothermal conversion efficiency was 94.2 % under standard sunlight intensity of 1 sun (1.0 kW m−2). Furthermore, the long-term stability and effective desalination capability of the RGOs-AgNPs/PVA solar evaporation device offer a potential opportunity for massive seawater desalination. Therefore, this work shows the prospect of combining flexible porous sponges with photothermal materials for practical solar evaporation. [Display omitted] •The prepared composite sponge has abundant porous structure for transporting water.•RGOs-AgNPs enhances the surficial hydrophobicity and reduces the accumulation of water on the surface.•The photothermal synergistic effect of RGOs-AgNPs enhances the water evaporation.•The prepared RGO-AgNPs/PVA displays a maximum evaporation rate of 2.09 kg m−2 h−1 under 1.0 sun.•The prepared RGOs-AgNPs/PVA has potential application in seawater desalination.