Sensitive nonenzymatic detection of glucose at PtPd/porous holey nitrogen-doped graphene

A facile, low cost and effective method was used to synthesize porous holey nitrogen-doped graphene (PHNG) with three-dimensional (3D) structure via direct pyrolysis of a mixture of urea and magnesium acetate tetrahydrate, followed by treating with hydrochloric acid to remove magnesium cations. The unique structure of PHNG significantly decreases the irreversible stacking of graphene nanosheet, favors the exposure of active edge sites, and enables more accessibility for reactants/electrolytes. The PHNG shows porous structure with a large surface area and can serve as support for nanoparticles. PtPd nanoparticles with different ratios were deposited on PHNG surface to synthesize PtPd/PHNG. The PtPd/PHNG-2 shows high direct oxidation activity towards the glucose, achieving a high sensitivity (52.526 μA mM⁻¹ cm⁻²), wide linear range (100–4000 μM), fast response time (<3 s), low limit of detection (1.82 μM), as well as high selectivity.