Carbon Nanomaterials as Renewable Water Purification Materials

Abstract

Globally, the scarcity of pure water has been an alarming threat for the survival of ecosystem since fresh water is the necessity of every being and is one of the most important factors in a healthy ecosystem. Potable or drinking water is meant to be free from all kinds of unwanted toxic chemicals, and its pH should always lie between 6.5 to 8.5. However, even today, knowingly or unknowingly, almost 30% in the world are drinking water with a pH below 6.5, which means it is acidic and contaminated with various kinds of pollutants. Even though, in some areas, freshwater is available, it is not affordable for the poor people in need. So, in the current situation, the most essential step is to adapt new trends and technologies for water purification using nature friendly and renewable resources. Emphasis is to be given to cost-effective, easy-to-use solutions for water purification, i.e., purifying water using carbon-based materials. In the present era, nanomaterials have emerged as the most sought-after and desirable solutions for various industrial problems and domestic applications. The carbon-based nanomaterials, including single and multi-walled carbon nanotube (CNTs), graphene oxide, activated carbons, carbon dot, and fullerenes are proposed as eco-friendly option. The introduction of carbon nanoparticles in water treatment is able to enhance the properties, such as fouling-resistance, permeability, catalytic activity, and stabilized water chemically and thermally. CNTs have been established as a great solution for water purification and treatment applications in recent times. Activated nano-carbon is widely employed in water purification because of good absorbing capacity and cost-effectiveness. It can absorb contaminants, including organic, inorganic, and biological from the water. Due to this adsorption property of the activated carbon, it plays a vital role in binding chemicals. Activated carbon takes away one or more atoms, molecules, or ions of contamination, when water passes through its surface. Molecular dynamics (MD) simulation facilitates such molecular-scale interaction for further scale-up of the treatment process. All these methods of water purification are gaining huge popularity due to their control over biofouling, superior structural properties, renewable, and eco-friendly nature.