Amperometric determination of H2O2 based on Prussian blue @ palladiumnanoparticles/graphene oxide nanocomposite modified electrode

Hydrogen peroxide (H2O2), a hazardous chemical, is known to be developing severe healthissues, widely used in various fields, involved in several biological events and intracellularpathways and is the by-product of oxidase enzyme-based catalyzed reactions. Therefore, it is veryimportant to develop rapid, simple, sensitive, inexpensive, reliable, and accurate H2O2 detectionsensors. Up to date, various analytical methods have been used for the accurate and sensitivedetermination of H2O2 [1-5]. Among these methods, electrochemical techniques have receivedextensive interest compared with the existing traditional methods. Nonenzymatic H2O2 sensorsbased on nanoscale materials have attracted much attention due to their unique characteristics,such as high sensitivity, large specific surface area, low detection limit, wide respond range andchemical stability [6]. To date, plenty of nanomaterials have been used to achieve a bettersensitivity and selectivity in the enzyme-free H2O2 sensors [5, 7, 8]. Transition metalhexacyanoferrates (Mhcf) have achieved significant interest due to their important properties suchas magnetism, electrochromism displays, electrocatalysts, and applications in sensor design andbatteries. Prussian blue (PB) has been described as ‘‘artificial peroxidase’’ for H2O2electrocatalysis. However, rapid desorption of PB film from electrode surface is the mainproblem that resulted in losing its catalytic activity. In order to overcome this problem, researchesfocused on developing methods for the synthesis of nanostructured PB objects and theirdeposition onto various conductive materials, such as carbon nanotube, graphene, bulk metalsubstrates and other substrates [9, 10]. The performance of the composite materials relies on theproperties of the individual components, and on the effective structural combination of thecomponents [11]. Here, we fabricated a new triple-component non-enzymatic sensor bysequential deposition of Pd and PB nanoparticles on GO modified PGE for the determination of H2O2. To create close contact between PB and GO we have electrodeposited Pd on GO modifiedPGE and used this electrode for the chemically deposition of PB because noble metals areactively promote the growth of PB. The resulting sensor combines the advantages of GO, Pd andPB nanoparticles and show good sensitivity and excellent electrocatalytic ability.This modified electrode was characterized by several techniques including scanning electronmicroscopy (SEM), energy dispersive X–ray spectroscopy (EDX), and cyclic voltammetry (CV).The sensor showed significantly better electrocatalytic activity for the reduction of hydrogenperoxide in comparison with the single GO/PGE, PB/GO/PGE and Pd/Go/PGE modifiedelectrodes. This was attributed to the synergistic effect of PB, Pd and GO nanoparticles. Also,this proposed sensor demonstrated an overall high level of performance for the analysis of H2O2using hydrodynamic amperometry in the concentration range from 0.2 mM to 0.5 mM anddetection limit of 0.049 mM with good stability, repeatability, and selectivity.

کلیدواژه ها:

Prussian blue ، Hydrogen peroxide reduction ، Electrocatalysis ، graphene oxide ، Pdnanoparticles