(a) Current/time recordings for successive additions of H2O2 at the graphene nanosheets (GNs) modified glass carbon electrode (GCE) GNs/GCE (labeled ‘a’) and Pt NP ensemble-on-graphene hybrid nanosheet modified GCE (PNEGHNs/GCE) (labeled ‘b’) measured at 0 V. (b) The plot of current of H2O2 versus its concentrations. (c) ASV curve of PNEGHNs/GCE in a phosphate buffered saline (PBS, pH = 9.4) in the presence of TNT with different concentrations at the scan rate of 50 mV s1. (d) The plot of currents of TNT versus its concentrations obtained at GNs/GCE (labeled ‘a’) and PNEGHNs/GCE (labeled ‘b’). Reproduced with permission from Ref. [85]. Copyright 2010, American Chemical Society.