Efficient nano-catalysts based-on metal nanoparticles (copper, silver and iron) supported on carbohydrate polymer (cotton cellulose) nanocomposite with long-term stability and efficient hydrogen production and removal of organic pollutants has been developed. The catalytic efficiency of the developed materials was evaluated in hydrogen production and reduction of organic pollutants, where it was found that copper nanoparticles supported on cotton cellulosic nanocomposite (Cu@CC) was much more efficient in hydrogen production and catalytic reduction of organic pollutants among all the tested catalysts. Cu@CC exhibited high catalytic activity in methanolysis of sodium borohydride with H2 generation rate of 1253 mLg-1 min-1 at room temperature. Further the catalytic activity, stability and re-usability of the prepared Cu@CC nanocatalysts were optimized by varying the amount of catalyst, amount of NaBH4, and concentration. Dyes and nitrophenols (NPs) were used as reaction models to determine the efficiency of the designed nanocatalysts for application in waste-water treatment, where Cu@CC was found more efficient for 4-nitrophenol (4-NP) and completely reduced it in 4 min. Further Cu@CC displayed efficient catalytic activity for the reduction of 4-NP in real samples like milk and juices.