A one-pot 'green' synthesis of Pd-decorated PEDOT nanospheres for nonenzymatic hydrogen peroxide sensing.

We developed a novel nonenzymatic biosensor based on palladium/poly(3,4-ethylenedioxythiophene) (Pd/PEDOT) nanocomposite modified glassy carbon electrode (GCE) for the detection of hydrogen peroxide (H2O2). Pd/PEDOT has been successfully fabricated by a facile one-pot 'green' method using H2PdCl4 as an oxidant and a source of metal nanoparticles without any surfactants and templates. The as-synthesized PEDOT nanospheres are quite uniform in size (~60 nm) without aggregation and provide a good platform for anchoring the Pd nanoparticles (NPs). Pd NPs (~4.5 nm) are homogenously dispersed on surface of PEDOT nanospheres. The Pd/PEDOT nanospheres on GCE exhibit a good electrocatalytic activity towards the H2O2 reduction. The electrochemical response of Pd/PEDOT to H2O2 exhibits a low detection limit of 2.84 μM in the range of 2.5×10(-3)-1.0 mM with a high sensitivity, good repeatability, acceptable reproducibility and good long-term stability. The good recoveries achieved in spiked human urine samples demonstrated the potential application of Pd/PEDOT for H2O2 detection.