Multi-bioinspired hierarchical integrated hydrogel for passive fog harvesting and solar-driven seawater desalination

Yi Zhang; Feifei Wang; Yongtao Yu; Jiajia Wu; Yingying Cai; Jian Shi; Hideaki Morikawa; Chunhong Zhu

doi:10.1016/j.cej.2023.143330

Multi-bioinspired hierarchical integrated hydrogel for passive fog harvesting and solar-driven seawater desalination

Chem Eng J. 2023 Jun 15:466:143330. doi: 10.1016/j.cej.2023.143330. Epub 2023 May 5.

Authors

Yi Zhang¹, Feifei Wang¹, Yongtao Yu¹, Jiajia Wu¹, Yingying Cai¹, Jian Shi², Hideaki Morikawa^{3

2}, Chunhong Zhu^{3

2}

Affiliations

¹ Graduate School of Medicine, Science and Technology, Shinshu University, 3-15-1 Tokida, Ueda, Nagano 386-8567, Japan.
² Faculty of Textile Science and Technology, Shinshu University, 3-15-1 Tokida, Ueda, Nagano 386-8567, Japan.
³ Institute for Fiber Engineering (IFES), Interdisciplinary Cluster for Cutting Edge Research (ICCER), Shinshu University, 3-15-1 Tokida, Ueda, Nagano 386-8567, Japan.

Abstract

In recent years, with the outbreak and epidemic of the novel coronavirus in the world, how to obtain clean water from the limited resources has become an urgent issue of concern to all mankind. Atmospheric water harvesting technology and solar-driven interfacial evaporation technology have shown great potential in seeking clean and sustainable water resources. Here, inspired by a variety of organisms in nature, a multi-functional hydrogel matrix composed of polyvinyl alcohol (PVA), sodium alginate (SA) cross-linked by borax as well as doped with zeolitic imidazolate framework material 67 (ZIF-67) and graphene owning macro/micro/nano hierarchical structure has successfully fabricated for producing clean water. The hydrogel not only can reach the average water harvesting ratio up to 22.44 g g^-1 under the condition of fog flow after 5 h, but also be capable of desorbing the harvested water with water release efficiency of 1.67 kg m^-2 h^-1 under 1 sun. In addition to excellent performance in passive fog harvesting, the evaporation rate over 1.89 kg m^-2 h^-1 is attained under 1 sun on natural seawater during long-term. This hydrogel indicates its potential in producing clean water resources in multiple scenarios in different dry or wet states, and which holds great promise for flexible electronic materials and sustainable sewage or wastewater treatment applications.

Keywords: Bioinspiration; Desalination; Hierarchical structure; Solar evaporation; Water harvesting.