Organic–inorganic hybrid membrane with anodized aluminum oxide support layer for improving membrane performance in forward osmosis

摘要

In the development of thin-film composite membranes for forward osmosis, the support layer is believed to have a fundamental role, which affects the membrane performance. However, the development of the support layer containing a high surface porosity, straight morphology of pores, and hydrophilic surface has been limited. Here, we report an organic-inorganic hybrid membrane fabricated with an anodized aluminum oxide (AAO) filter as a support layer, which has a high surface porosity, straight pores (tortuosity similar to 1), and hydrophilic surface. The organic-inorganic hybrid membrane was fabricated by attaching a polyamide thin-selective layer on an AAO filter, which was coated with poly(dopamine). The polyamide thin-selective layer was separated from the polyamide-polysulfone traditional membrane by selectively melting the polysulfone support layer. The membrane performance of the fabricated hybrid membrane was significantly enhanced compared with that of the polyamide-polysulfone membrane because of the diminished salt resistivity by the high surface porosity, unity tortuosity, and surface chemistry of the support layer.