The pollution of the majority of the world's water sources and the consequent looming clean drinking water free of pollutants and groundwater pollution which threatens the human and the ecosystem are some of the major concerns faced by the world. The various contaminants from different industrial, agricultural and domestic sources such as pesticides, other chemical contaminants, the heavy metal ions: Hg (II), Pb (II), Cd (II), and As (III) which pollute the water sources are highly toxic and are capable of causing life-threatening diseases to humans. Cost-effective adsorbent materials with high metal ion-removal efficiency and selectivity are considered necessary for the successful removal of these contaminants from water. Our group has studied the removal of heavy metal ions contamination from drinking water because of their high-level toxicity and the ultra-low safe level (Hg (II) ≤ 2ppb, Pb (II) ≤ 10 ppb, Cd (II) ≤ 5 ppb) in water which is very challenging to achieve. In order for this we have utilized molybdenum disulfide (MoS2)/graphene-based materials for the removal of toxic metal ions: Hg (II) and Pb (II) with very high selectivity and efficiency. One of the materials synthesized, MoS2-hollow nano roses (HNR) achieved ~ 99.99 % removal of Hg (II) from environmental water samples spiked with 10000 ppb within ≤ 5 minutes, and another material, partially reduced graphene (prGO)-MoS2 nanocomposite), decreased the [Pb (II)] to ≤ 1 ppb in and ≤ 3 minutes, respectively, with a single treatment. Figure 2 gives an overview of some of the adsorption results from our group