Reduced Graphene Oxide – Silver Nanocomposite Synthesis – rGO-Ag by using Graphene Oxide, Silver Nitrate and Hydrazine Hydrate via Chemical Reduction Method

Reduced Graphene Oxide – Silver (rGO-Ag) Nanocomposite Synthesis by using Graphene Oxide as precursor, Silver Nitrate as precursor and Hydrazine Hydrate as reducing agent via Chemical Reduction Method.

1. CHECK LIST

   Graphene Oxide (GO), Silver Nitrate, Sodium Hydroxide, Hydrazine Hydrate, Deionized Water, RB Flask, Dropper, Magnetic Stirrer.

   

2. STEP 1.

   Add 500mg Graphene Oxide in 150ml deionized water and sonicate for 40 minutes.

   

3. STEP 2.

   Add 4g Sodium Hydroxide in 100ml deionized water.

   

4. STEP 3.

   Add Sodium Hydroxide solution (prepared in step-2) in GO solution (prepared in step-1) and sonicate again for 20 minutes.

   

5. STEP 4.

   Add 50mg Silver Acetate in 100ml deionized water.

   

6. STEP 5.

   Add Silver Acetate solution (prepared in step-4) in GO solution solution (prepared in step-3).

   

7. STEP 6.

   Add 3ml (of 10%) Hydrazine Hydrate and setup reflux at 80ºC for 24 hours.

   

8. STEP 7.

   After 24 hours remove the reflux; filter out the rGO/Ag composite; and wash with deionized water several times.

   

9. RESULTS

   Reduced Graphene Oxide colour would be black; Raman spectroscopy will show a peak around 440cm-1. You will also get a peak around 380nm and 420nm in UV-Vis Spectrosocpy.

   

10. Factors Affecting Synthesis

    Concentration of Graphene Oxide: The first main ingredient for the synthesis of rGO/Ag composite is Graphene Oxide. As much concentration we take initially, that much amount rGO we get at the end of the process. But much higher amount of Graphene Oxide can leads to incomplete reduction and thus bad quality final product.
    Concentration of Silver Precursor: Second main salt in this synthesis is Silver Nitrate. If concentrate of Silver Nitrate is increased, then amount of reducing agent (i.e. Hydrazine Hydrate) should also be increased. Much higher concentration of Silver Nitrate will lead to bigger particles of Silver in the final composite.
    Concentration of Hydrazine Hydrate: Hydrazine Hydrate acts as the reducing agent in synthesis method. For the optimum reduction of Graphene Oxide and Silver Nitrate, optimum quantity of Hydrazine Hydrate is properly needed.
    Effect of Temperature: Temperature plays an important role in speeding up any reaction. High temperature synthesis give us fine product quality by consuming less time.
    Why Reflux: Reflux is a very good technique, when we want to give temperature to the solvents just below their boiling point. In this synthesis method, if we do not use reflux and direct heat the solution for 24 hours. Then all the water will be evaporated within few hours and only solid non-reduced GO will be left in the RB flask.

11. NOTE: All the experiments should be done under the guidance of lab Incharge; and proper lab safety instructions.