Solar‐Driven Airflow‐Enhanced All‐Daytime Solar Steam Generation Based on Inverse‐Bowl‐Shaped Graphene Aerogels

Abstract

Solar steam generation (SSG) is a promising approach to solve the shortage of fresh water resources. Despite intensive research on photothermal materials, the SSG performance is still unsatisfactory for practical applications. Moreover, the actual solar trajectory is a semicircular arc, resulting in a continuous change of the incident angle, which is often ignored in previous reports. Herein, an inverse‐bowl‐shaped graphene aerogel (IBGA) is synthesized as the photothermal component for the SSG, which can always maintain a high water evaporation rate with the change of the incident angles. Furthermore, a solar‐driven airflow is introduced based on a modified Stirling engine to enhance the SSG performance. The SSG device based on IBGA with solar‐driven airflow exhibits a high evaporation rate of 2.46 kg m−2 h−1 under 1 sun irradiation. The outdoor experiments demonstrate that an SSG device with 1 m2 of IBGA can collect 15 kg freshwater on a sunny day, showing great potential for seawater desalination and wastewater treatments in practical applications.