**4. Conclusion**

Membranes containing nanomaterials in the form of MMNMs or TFN, ensure outstanding features in terms of permeability, selectivity, antifouling, and selfcleaning ability for water applications due to their synergistic effects. However, there are still major challenges to developing high-performance membranes for large scale water treatments. Difficulties in dispersion of inorganic nanoparticles in a polymer matrix, the release of nanoparticles and associated environmental toxicity, long term stability, and the production cost of the nanocomposite membrane, needs to be further explored. Care should be taken that the nanoparticles selected do not sacrifice an ability of the membranes to improve another ability.
