Protonated carbon nitride induced hierarchically ordered Fe2O3/HC3N4/rGO architecture with enhanced electrochemical sensing of nitrite

A novel electrochemical nitrite (NaNO 2 ) sensor is fabricated by combining Fe 2 O 3 with protonated carbon nitride (H C 3 N 4 ) and reduced graphene oxide (rGO). The smaller H C 3 N 4 is distributed uniformly on the surface of the rGO support and acts as a nucleation site for the growth of Fe 2 O 3 . Conductive H C 3 N 4 is a nano-bridge to connect and uniformly distribute Fe 2 O 3 , a catalytic center, to the support rGO to enhance the electrocatalytic performance. The Fe 2 O 3 /H C 3 N 4 /rGO electrode possesses high sensitivity of 0.04874 μA μM −1 , wide linear response range spanning 25 nM to 3000 μM, a low detection limit of 18.55 nM (S/N = 3) and shows high selectivity for nitrite in the presence of common organic and inorganic interfering species (like NaCl, MgSO 4 , KNO 3 , ZnSO 4 , CaCl 2 , glucose, urea), fulfilling requirements for a nitrite sensor used in commercial applications.