## Nanomaterial-Based Membrane
### Polymer Nanocomposites Membranes for the Treatment of Wastewater
The membranes were also structurally characterized. The carbon nanotube composite membrane structures expressively revealed enhanced performance when likened to pure self-supporting carbon nanotube. The best carbon nanotube composite membranes attained higher permeabilities with 95% rejection of salt with a 39 h lifespan under continuous operation, which accords them prospective candidates for direct contact membrane distillation. [PERSON] et al. synthesized a membrane from carbon nanotube-polymer composite using a polyvinyl alcohol barricade stratum for the separation of oil from wastewater [50]. The synthesis of carbon nanotubes was done via chemical vapour deposition with the employment of a phase inversion technique for mixing carbon nanotubes in a solution that is made of polymer composite, which was used for fabricating the membrane. The permeate demonstrates that concentrations of oil lower the conventional limits of 10 mgL\({}^{-1}\), with an outstanding throughput and more than 95% rejection of oil was achieved [50]. [PERSON] et al. synthesized a 1.5 nm diameter carbon nan otubes membrane with two zwitter ions at tip tails and attained ion retention of 100% [51]. [PERSON] et al. recently proposed an innovative polyphenol-metal influenced nanohybridization approach for the purpose of fabricating anti-oil-fouling carbon nanotube membranes to obtain excellent-flux, antifouling, and separation of self-cleaning oil/water [52]. The proposal was attained by taking into account facile synchronization arrangement and the strong metal ion embarkment competency of tannic-metal synchronization multiplexes. The polyphenol-metal influenced the nanohybridization approach, which falls within the arrangement of polyphenol-metal (chitosan/tannic acid-Fe\({}^{3+}\)) multifaceted primer on the carbon nanotube membranes through an in situ FeOOH nanorods mineralizing process. The carbon nanotube-chitosan/tannic-FeOOH nano-hybrid membrane attained excellent water permeability and notable high water recovery ratio [52]. In order to curtail fouling, diverse kinds of nanoparticles have been integrated into polymeric membrane matrices to reduce membrane hydrophobicity, membrane roughness, and improve surface properties [35]. Nanosilver (nAg) particles are effectual and are recognized as antibacterial agents. nAg could be integrated into membrane as a nano filler to neutralize microorganisms in the course of filtration [53], hence reducing membrane biofouling ([PERSON] et al., 2010). Nanosilver particles antimicrobial effects could be ascribed to their ability to interrupt the functions of cell membrane, disturb electron transport chains, and destroy cell protein and deoxyribonucleic acid [54]. Diverse oxidation states of silver (Ag\({}^{0}\), Ag\({}^{+}\), Ag\({}^{2+}\)) have been examined in biopolymer composite membranes [55]. The integration of nAg in membranes basically offer the capability of improving the properties of membrane anti-bifouling; however, they are usually not effective in enhancing the permeability and rejection ratio of the membrane [44]. [PERSON] et al. investigated the influence of silver-nanoparticles locality in three different forms of polymer [56]. Three different polymers--polyethersulfone, polysulfone, and cellulose acetate--were utilized for synthetizing nanocomposite membranes at three diverse silver-nanoparticles ratios. A comprehensive account of how the location of silver-nanoparticles changes was reported in the study. The comprehensive account was dependent on the forms of polymer and the subsequent impact this locality has on the antibacterial properties of the membranes. It was reported that silver-nanoparticles are homogeneously positioned alongside the membrane matrix of both skin stratum and sub-stratum; however, they bulged from the top surfaces of polysulfone and polyethersulfone membranes.