Tri-dimensional porous cattails carbon fiber/MoS2 composite aerogel for desalination and oil–water emulsion purification

Abstract

Solar-driven interfacial evaporation technology presents a novel strategy for tackling water shortage challenges. Nevertheless, the evaporation efficiency and long-term stability of solar interfacial evaporation materials remain critical challenges in advancing their application in desalination and wastewater treatment. In response, this research unveils an innovative aerogel-based interfacial evaporation material. This material cleverly integrates the broadband light absorption characteristics of cattail carbon fibers (CCF) and MoS₂, thereby facilitating highly efficient photothermal conversion. Additionally, polyvinyl alcohol (PVA) and chitosan (CS) serve as the structural backbone. By introducing aminopropyl trimethoxysilane (APTES) and hydroxyapatite (HAP), and employing a straightforward chemical and ionic crosslinking process, a composite aerogel with three-dimensional porous characteristics and superhydrophilicity was successfully fabricated. Under simulated one-sun intensity illumination (1 kW/m²), this aerogel exhibited exceptional evaporation rates (2.065 kg m^-2h⁻¹) and efficiency (99.54 %), surpassing the performance of some previously reported aerogel-based interfacial evaporation materials. Notably, during consecutive 20-cycle evaporation tests in 3.5 wt% saline water, the material maintained stable evaporation performance without any observable salt deposition on its surface. This advantage stems from its unique porous structure and superhydrophilicity, ensuring sufficient water supply during evaporation to dissolve and remove salts effectively. Furthermore, the aerogel demonstrates exceptional underwater superoleophobicity, exhibiting significant potential for the purification of oil-in-water emulsions. In summary, this 3D porous composite aerogel interfacial evaporation material offers a promising new approach for desalination and water purification.