Synthesis and Comparative Electrocatalytic Evaluation of Chromium Chalcogenides Nanoparticles for Overall Water Splitting

Electrochemical water splitting is a promising route for sustainable hydrogen generation, but its progress is constrained by sluggish kinetics and the scarcity of cost-effective bifunctional catalysts. While transition metal chalcogenides have been widely studied, chromium chalcogenides remain underexplored, particularly for water splitting. In this work, we address this gap by synthesizing chromium sulfide, selenide, and telluride nanoparticles (Cr₂S₃, Cr₂Se₃, Cr₂Te₃) through solvo- and hydrothermal methods and systematically assessing their activity for both hydrogen and oxygen evolution reactions. Structural, morphological, and surface characterizations (XRD, SEM/TEM, Raman, and XPS) confirm well crystalline nanoscale particles, while electrochemical evaluation reveals Cr₂S₃ as the most active, requiring only 228.5 mV for OER and 93 mV for HER at 10 mA cm−². It also exhibits the lowest charge transfer resistance and stable operation over 24 h. These findings establish chromium chalcogenides as a promising platform for advancing non-noble bifunctional catalysts in integrated water splitting technologies.