Nickel Lanthanum Telluride Nanofibers as an Efficient Bifunctional Electrocatalyst for Water Splitting

Water electrolysis has emerged as a promising pathway for sustainable energy production, highlighting the need for innovative nonprecious bimetallic nanocatalysts to enhance overall reaction efficiency and kinetics. In this study, we report the synthesis and bifunctional electrocatalytic performance of nanoscale nickel lanthanum telluride nanofibers (NiLaTe NFs) for both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER). These nanostructured fibers were fabricated via a simple oven-based wet chemical route, enabling binder-free in situ growth on Ni foam. Structural analysis revealed a uniform one-dimensional (1D) nanoscale architecture composed of mixed-phase NiTe (hexagonal) and La₂Te₃ (cubic), with homogeneous nanoscale dispersion of Ni, La, and Te elements. Additionally, the influence of Ni and La precursor ratios on the resulting structural characteristics was systematically investigated by using FESEM. The contribution of elemental Te was also examined to elucidate its impact on the development of the nanofibril morphology. The nanostructured NiLaTe NFs outperformed their monometallic counterparts (NiTe and La₂Te₃) and even benchmark RuO₂, exhibiting low overpotentials of 186 mV for HER and 332 mV for OER, demonstrating efficient performance for overall water splitting. The enhanced electrocatalytic activity is attributed to nanoscale electronic coupling between Ni, La, and Te, which facilitates rapid charge transfer and active site exposure in its bimetallic system as compared with its monometallic counterparts. Moreover, the 1D nanomorphology enhances the surface area and conductivity, further boosting catalytic performance. This work amplifies the critical role of nanoscale engineering in developing high-efficiency, nonprecious bifunctional electrocatalysts for overall water splitting.