ELECTROCATALYTIC HYDROGEN RELEASE AT A GLASSY CARBON ELECTRODE MODIFIED WITH A NICKEL-CONTAINING NANOTUBE COMPOSITE

Composites based on the nickel-containing biopolymer complex Ni(20%)-NaPG , possessing catalytic properties in the reaction of hydrogen evolution were obtained and studied. When creating the composite, TUBALL carbon nanotubes were introduced into it to increase reactivity and electrical conductivity. Cyclic voltammetry showed that the use of carbon nanotubes with the Ni(20%)-NaPG complex in catalytic inks provides a decrease in the overpotential of the hydrogen evolution reaction by 65 mV relative to the unmodified glassy carbon electrode. The amplitude of the cathode current at a potential of -1.5 V on the electrode with carbon nanotubes and the Ni(20%)-NaPG complex is 2.34 times higher relative to the unmodified glassy carbon electrode. A comparison was also made of the overpotential of the hydrogen evolution reaction of composites with nanotubes and composites made using VULCAN XC72 carbon black, which is widely used in the creation of electrocatalyst electrodes. The surface morphology of the modified electrodes before and after the introduction of nanotubes was studied using scanning electron microscopy. It was shown that a developed structure was formed on the surface of glassy carbon with a composite containing carbon nanotubes, where nanotubes with an average thickness of 15-20 nm are visible. The elemental composition of the surface of the modified electrodes, obtained using energy-dispersive X-ray spectroscopy, showed the presence of nickel and sodium, which are present in the complex. The results obtained showed a significant increase in the current in the region of hydrogen evolution due to the use of carbon nanotubes as conductive structures in the composite catalytic ink with the biopolymer complex Ni(20%)-NaPG , which confirms the prospects of the chosen research direction.