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Interaction between reduced graphene oxide (rGO) and PbSe quantum dots (Q-PbSe) have been studied by Cyclic Voltammetry (CV), Raman and FTIR spectroscopy. For that, the composites of Q-PbSe and rGO have been prepared by a one pot synthesis method. From the TEM analysis, Q-dots decorated on graphene layer have been concluded. Cyclic Voltammetry techniques have been employed to determine the change in quasi-particle gap and band edge parameters of Q-PbSe due to the interaction with rGO. The results were corroborated with FTIR and Raman analysis where substantial change in IR bands and shift in the Raman peaks have been observed, due to the interaction between Q-PbSe and rGO. [ABSTRACT FROM AUTHOR]

Electrodics of hydrogen evolution reaction (HER) has been studied for N-doped graphene oxide (N-GO) based electrodes with varied N-content; from graphene oxide (0% Nitrogen) to graphitic carbon nitride (GCN, 66.6% Nitrogen). In between compositions have been prepared by co-heating GO with melamine. These were characterized in detail by XRD, Raman, FESEM, EDAX, XPS, FTIR and Thermal analysis. Electrodics of HER have been studied by cyclic voltammetry (CV), linear sweep voltammetry (LSV) and forced convection hydrodynamic methods using Rotating Disc Electrode (RDE). The overpotential for the HER have been noted to decease systematically with an increase in the N-content and attend minima at −0.21V vs. RHE for GCN. Tafel plot based on exchange current density (J o ) have been increased in sigmoidal fashion with N-content and saturated for GCN at ∼0.1 mA cm −2 . This value is almost double comparable to the one reported for 3D-MoS 2 ; the best non-platinum catalyst known for HER, to date. The standard rate constants (k°) as a function of composition have been estimated from Koutecky-Levich plots. These values have been increased systematically with increase in the N-content from ∼10 −5 cm s −1 for GO to more than 10 −3 cm s −1 in case of GCN. [ABSTRACT FROM AUTHOR]

Graphene oxide decorated with silver nanoparticles (GO-Ag) was prepared by anodic dissolution of silver in the aqueous dispersion of GO. The composites were characterized by XRD, XPS, TEM, AFM, and Raman spectroscopy. The electrooxidation of glucose on GO-Ag modified electrodes have been tested by cyclic voltammetry and chronoamperometry. The detail mechanism of redox processes on the GO-Ag electrodes has been studied. A few μg loading of silver has demonstrated to give current in μA for the mM concentration of glucose. A linear relationship between peak height in the voltammograms and glucose concentration in the range 1–14 mM has been proposed for amperometric detection of glucose. From the results, the detection limit for glucose sensing is estimated to be as small as 4 μM. The selectivity for glucose in presence of interfering molecules viz. ascorbic and uric acids is tested. Proof-of concept is presented by carrying out the measurements in real human blood samples. [ABSTRACT FROM AUTHOR]