In this work, nitrogen and phosphorus co-doped reduced graphene oxide (N, P-rGO) nanohybrids has been synthesized using one pot greener in situ method using cytidine monophosphate as a dopant/reducing agent. This material has been characterized by various techniques such as UV-Vis, Raman, FE-SEM, TEM and thermal methods (TGA). The stability of N, P-rGO as an electrode material and the high operational potential window of 2.7 V (from -1.4 to 1.3 V) was achieved in three-electrode setup after running 150 electrochemical cyclic voltammetry (CV) cycles in neutral WIS 17 m NaClO4 electrolyte. Two-electrode aqueous symmetric supercapacitor (SSC) (N, P-rGO//N, P-rGO), designed by using CMP-mediated N, P-rGO as electrode material in neutral WIS 17 m NaClO4 electrolyte provided a fairly high energy density of 42.2 Wh Kg-1 at a power density of 315.2 W Kg-1 at 0.7 Ag-1 with superior cyclic stability, making it sustainable for energy storage applications. The ClO4- anion has been suggested to act as an effective H-bond net-work breaker for the bulk water, thereby, enhancing the cell voltage to 2.7 V. To the best of our knowledge, this system demonstrates a very high cell voltage for N, P-co-doped reduced graphene oxide with a high energy density