Preparation of hierarchically porous ANF/CNT aerogel and its solar-driven high-efficiency desalination performance

Against the backdrop of the global shortage of freshwater resources, solar steam regeneration technology has attracted significant attention due to its great potential for efficient seawater desalination. However, the complex system architecture and high manufacturing costs have hindered its large - scale economic application. In this study, an integrated solar - driven interfacial evaporator based on aramid nanofiber (ANF) and carbon nanotube (CNT) composite nanofiber aerogel was developed. Through vacuum - assisted filtration combined with directional freezing technology, an ANF/CNT aerogel with vertical channels and a transverse layered structure was successfully constructed, achieving both efficient photothermal evaporation and mechanical extrusion desalination functions. The evaporation rate of the ANF/CNT - 30% aerogel for simulated seawater reached 2.04 kg·m −2 ·h −1 , and its net evaporation rate was 1.51 times that of dark evaporation, confirming that the directional structure significantly improves the evaporation efficiency. During the 7 – day continuous operation, the daily pure water production rate (8 h) of the device reached 19.0 L·m −2 , and the internal salt was effectively removed through cyclic extrusion, ensuring the long - term stability of the aerogel. This integrated structure design and simple preparation process endow the ANF/CNT aerogel with significant cost advantages and application potential, providing an innovative solution for high - efficiency and low - consumption seawater desalination technology.