Title: PVDF/Graphene/catalyst multifunctional intelligent composite membrane for sustainable regeneration of clean water and energy

Conference Name: 13th International Congress on Membranes and Membrane Processes 2023 (ICOM2023)

Award: Desalination/Poster

Abstract: 

Due to rapid social development and population growth, the world faces waer and energy shortages continuously. Membranes are recognized as one of the more favorable solutions, but there are still certain limitations such as fouling problems under long-term operation. Hence, in this study, a PVDF/graphene/catalyst multifunctional intelligent membrane was prepared, which has a piezoelectric effect, photothermal effect, photocatalytic effect, and good conductivity. 

The wet phase conversion process and the addition of graphene induced the PVDF crystal phase transfer from α to electroactive β phase, resulting in a membrane that has excellent piezoelectric properties which can effectively convert wave energy into electricity and generate 12 V (±6 V) under 2 Hz simulated impact. At the same time, the synergistic effect of the piezoelectric effect and photocatalytic effect greatly improves the degradation efficiency of congo red. Using solar/ultrasonic as the excitation source, the piezo-photocatalytic dye degradation efficiency was measured to be 93%. On the other hand, the good light absorption and the microporous structure formed by stacked graphene and polymer make the membrane to be an excellent solar evaporator, where the clean water production rate can reach 3.07 kgm-2 in one hour under one sun illumination. Finally, the conductivity and inverse piezoelectric property of the membrane enable it to have the ability of self-monitoring and self-cleaning, which can effectively judge the resistance change during fouling. This study prepared a composite membrane through various synergistic effects. As a water/electricity regeneration device, not only it can simultaneously obtain fresh water and electricity, degrade pollutants, and monitor pollution level, but it also proposes a new direction and possibility for the development of sustainable water and energy regeneration.