Demands on superhydrophobic, self-cleaning and piezoelectric membranes have gained significantly due to their potential to overcome global shortages in clean water and energy. In this study, we have discovered a novel plasma-assisted nonsolvent induced phase separation (PANIPS) method to prepare superhydrophobic, self-cleaning and piezoelectric PVDF membranes without additional chemical modifications or post-treatments. The PANIPS membranes exhibit remarkable water contact angles ranging from 151.2° to 166.4° and sliding angles between 6.7° and 29.7°. Moreover, the PANIPS method also induces a rapid α/β → β/γ phase transition in the PVDF membranes, significantly enhancing their piezoelectric responses from 0.73 Vpp to 10 Vpp. The mechanism behind PANIPS involves the bombardment of water ion clusters that locally coarsens the membrane surface, leading to a highly porous and hierarchical micro/nanostructured morphology. The anti-wetting ability of the PANIPS membranes was confirmed by direct contact membrane distillation (DCMD) tests to treat the hypersaline solutions containing 10 wt% NaCl and a Rose Bengal dye of 1000 ppm. This study may provide valuable insights to fabricate PANIPS membranes and open up new avenues to molecularly design advanced superhydrophobic, self-cleaning, and piezoelectric membranes in the fields of clean water production, motion sensor, piezoelectric nanogenerator and CO2 capture.
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