Biomimetic materials for efficient emulsion separation: Based on the perspective of energy

Purifying emulsified oily wastewater is particularly crucial for solving environmental pollution and water scarcity. Membrane separation shows great potential for emulsified wastewater treatment. However, realizing continued effective emulsion separation remains a significant challenge. Fortunately, various kinds of creative schemes have been proposed to overcome the current dilemma. In this paper, biomimetic emulsion separation materials with unique wettability are introduced. Besides, This article summarizes the recently advanced emulsion separation strategies. First, we analyze the typical wettability theory and explore the trade-off between separation flux and efficiency. After that, based on emulsion types, the current common emulsion separation materials are summarized and analyzed. Notably, the integration of natural biological inspiration has made separation materials full of potential. Further, from the perspective of external energy input or no-external energy input, this article provides an overview of advanced emulsion separation materials and analyzes the potential separation mechanism. Encouragingly, efficient emulsion separation can be realized by membrane characteristics (microstructure, superwettability, electrostatic interaction) or the appropriate external stimulus (photo, electricity, magnetic). Finally, the challenges and trends are summarized. We hope that this article will provide inspiration for the advancement of novel generations of separation materials.