Nanotechnology can be a part of future solutions for water/wastewater treatment, which is highly complex and has to be affordable. I am always very sceptical about news of 'ground braking' 'game changing' solutions, which likely cannot cope with complexity of practical wastewater treatment like fouling and seem to be associated with huge costs.

Every research in this direction should test under real world conditions on an early stage, keep prospected cost low and search for synergy with traditional technologies.