PdAg-decorated three-dimensional reduced graphene oxide-multi-walled carbon nanotube hierarchical nanostructures for high-performance hydrogen peroxide sensing

High-performance electrochemical hydrogen peroxide (H2O2) sensors based on PdAg nanoparticle-decorated reduced graphene oxide (rGO) and multi-walled carbon nanotube (MWCNT) hybrids were developed. The nanostructures were characterized using transmission electron microscopy, scanning electron microscopy, energy-dispersive spectroscopy. thermogravimetric analysis, Fourier transform spectroscopy. and x-ray diffraction techniques. It was found that introduction of MWCNT in the catalyst layer improved the sensitivity and widened the linear range. Sensitivities of 393.2, 437.1, and 576.6 mu A/mM/cm(2) were obtained for PdAg/rGO-MWCNT (2:1), PdAg/rGO-MWCNT (1:1), and PdAg/rGO-MWCNT (1:2), respectively. Furthermore, hierarchical structure of rGO-MWCNT nanohybrids enabled the detection of H2O2 up to 80 mM.