Designing energy-efficient separation membranes: Knowledge from nature for a sustainable future

Membrane separation has provided efficient solutions for addressing energy and environmental challenges over the past few decades due to its low energy consumption, convenient operation, and reduced secondary pollution. An energy-efficient membrane separation process usually requires high-performance membranes with outstanding chemical, mechanical properties, special nanostructures, and superior separation characteristics. Hence, considerable effort has been devoted to finding and designing new membrane materials with optimized membrane structures. In recent years, researchers have gained deep knowledge of learning biomimetic concepts or strategies from nature for designing energy-efficient separation membranes with favorable structures. This is because, after 4.5 billion years of evolution, the world of nature has become a natural school for scientists and engineers, which has offered astonishing solutions/inspirations for designing more sustainable separation materials. In this review, particular attention is paid to knowledge from nature for the design of separation membranes and recent advancements in their design strategies. Additionally, natural functional materials that have been utilized in the replacement of conventional fossil-based materials for membrane production are reviewed. Present challenges and directions for the development of next-generation membranes are also discussed.