Akademik Veri Yönetim Sistemi
International Journal of Hydrogen Energy, 2025 (SCI-Expanded)
Developing efficient and available catalysts is important for advancing hydrogen evolution reaction (HER) in alkaline water electrolysis, a promising technology for sustainable hydrogen production. This study reports the synthesis and electrochemical performance of Bi2S3 and NiBiS3 catalysts for the HER in alkaline water electrolysis. The catalysts were prepared via a hydrothermal method and characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). The electrochemical behavior was evaluated using cyclic voltammetry (CV), cathodic current-potential curves (Tafel polarization), electrochemical impedance spectroscopy (EIS), and chronoamperometry (CA) in 1 M KOH. The graphite electrode modified with NiBiS3 exhibited high catalytic activity. The significant increase in current density and decrease in polarization resistance from 3000 Ω cm2 (bare graphite) to 18.55 Ω cm2 were detected. The G/NiBiS3 electrode outperformed both the bare graphite and G/Bi2S3 electrodes, with the current density reaching −2.3 × 10−3 A cm−2 at −0.26 V. Morphological analysis revealed that Bi2S3 forms flower-like structures, while NiBiS3 exhibits a cauliflower-like morphology, providing increased active surface areas important for catalytic activity. The Tafel slope analysis confirmed the Volmer step as the rate-determining step in the HER mechanism, with the adsorbed hydrogen subsequently forming molecular hydrogen. Stability testing through CA demonstrated consistent catalytic activity, with the current density maintained at −0.014 A cm−2 over 75000 s. These findings demonstrate the potential of NiBiS3 as a reliable and effective catalyst for alkaline electrolysis-based sustainable hydrogen production.