Investigation on rapid solar evaporation, over 100% evaporation efficiency, and LCA of a lotus-like multi-layer PVA-based aerogel

Solar interface evaporator has been played an increasingly important role for sewage treatment and desalination, etc. due to its processability, comprehensive application. However, for instance, energy collection rate and utilization efficiency for solar interface evaporation has still an urgent need for improvement. Hence, a series of MXene/ reduced carboxylated carbon nanotubes (RCNT)/ Polyvinyl alcohol (PVA) (MCP) solution were directional frozen and then dried by low-temperature vacuum method to successfully prepare a bionic lotus-like multi-layer PVA-based aerogel. Particularly, when the component ratio of the MXene: RCNT: PVA was 6: 24: 70, the water and brine evaporation rate of M 6 /C 24 /P 70 composite aerogel reached respectively 3.35 kg·m −2 ·h −1 and 2.51 kg·m −2 ·h −1 , while for the PVA aerogel were just 0.63 kg·m −2 ·h −1 and 0.37 kg·m −2 ·h −1 . Importantly, the evaporation efficiency for the M 6 /C 24 /P 70 can achieve 132.7 %, which exceeds that of most of evaporators in the published reports and the phenomenon was defined firstly self-accelerating evaporation. This work not only explores the preparation strategy for the distinguished biomimetic solar-derived evaporator, but also broadens the functional application scope of PVA-based aerogels.