Hydrogen evolution reaction activity of 3D-printed TiB2 and MgB2 matrix reinforced with graphene and carbon nanofiber in alkaline media

In the present study, the TiB_2, MgB₂/ Graphene (GRP)/PLA and TiB₂, MgB₂/Carbon Nanofiber (CNF)/PLA 3D-printed electrodes were fabricated via the Fused Deposition Modeling (FDM) technique. The hydrogen Evolution Reaction (HER) performance of 3D electrodes was studied using electrochemical impedance spectroscopy (EIS) and cathodic polarization analysis methods in 1 M KOH media. The EIS measurement results showed that the total resistance values  were significantly reduced due to the addition of GRP and CNF to TiB₂/PLA and MgB₂/PLA 3D electrodes. In addition, the increase in current density with the addition of GRP and CNF to the 3D electrodes from the cathodic polarization curves supported the EIS measurement results. Moreover, a new activation method without using solvent was applied as different from the literature, to enhance the conductivity of 3D electrodes. The activation process was performed by implementing 50 cycles in 1 M KOH solution with the cyclic voltammetry method. As a result, with this study, both the synergistic effect of multiple composites and the application of the activation method have increased the HER efficiency of the 3D electrocatalyst. Thus, 3D electrocatalysts have been introduced to the energy application field.