The present work reports a simple and effective way to produce hydrophobic foams with polyvinylidene fluoride (PVDF) and TiO2 by using a phase separation technique. This method involved the phase separation during the deposition of PVDF from its DMF solution with nonsolvent water in the presence of TiO2. The surface morphology of hydrophobic surfaces was characterized by Field Emission Scanning Electron Microscope (FESEM). The maximum water contact angle of 129° was observed. The results confirm that the surface texture of polymer composite exhibits mixture of microporous and nanoporous structure. The impact of TiO2 on the wettability property of polymer composite has been studied. The proposed methodology might find applications in the preparation of hydrophobic surfaces for industrial applications. 1. Introduction The excellent water repellent surface is exhibited by the leaves of？？the lotus flower. These leaves are superhydrophobic; that is, water drops roll over, taking any impurities with it. The combination of surface roughness and water-repellent wax crystals gives superhydrophobic property. The fabrication of a superhydrophobic surface depends on the surface roughness and surface energy of materials [1]. Many artificial methods have been developed to fabricate superhydrophobic surfaces using techniques such as electrodeposition, plasma etching, laser treatment, sol-gel method, and solution immersion method. Phase separation method is an important technique for development of super hydrophobic surfaces [2, 3]. In this method, the product should be separated into a different phase from everything else that is present in the final reaction mixture. The phase separation method is the simplest method compared to the other methods mentioned above and the ease in forming large area and strong superhydrophobic coatings [4]. The process of？？harnessing and converting ambient energy sources into usable electrical energy is called energy harvesting. Piezoelectric materials can be used to harvest energy since they have the unique ability of converting mechanical strain energy into useful electrical energy [5]. Polyvinylidene fluoride (PVDF) is a piezoelectric polymer which exhibits hydrophobicity and can be employed in energy harvesting applications like sensors and actuators [6]. Compared to strain gauges, piezoelectric sensors offer superior signal-to-noise ratio and better high-frequency noise rejection. Piezoelectric sensors are, therefore, quite suitable for applications that involve measuring low strain levels [7]. They are compact and easy to embed
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