Simple Hierarchical Interface Design Strategy for Accelerating Solar Evaporation

Abstract

AbstractInterface design is an efficient way to improve the steam generation performance of solar evaporators. Accompanied with the formation of cellulose nanofiber/polylactic acid/polyaniline (PANI) hybrid aerogel (HA) by Pickering emulsion and in situ polymerization, this paper proposes a new perspective of hierarchical interface design strategy to accelerate the water evaporation driven by solar energy. By changing the concentration and type of doped acid, the distribution gap of different PANI forms in HA can be microscopically designed. PANI nanoclusters with smaller gaps facilitate HA to achieve an improved light absorption, photothermal conversion capability and steam generation rate. Moreover, macro interface design introduces hemispherical depression structures to the HA surface through a simple mold. These recessed surfaces not only increase the light absorption by increasing the multiple reflections and refractions of light on the recesses, but also recover part of the heat radiation loss to the environment. A higher evaporation rate of 1.65 kg m−2 h−1 with a steam generation efficiency of 94.6% is achieved under the irradiation of 1 Sun (100 mw cm−2). Finally, HAs have strong purification ability for various raw water, and are promising in terms of their application potential in the field of energy conversion.