CoTe Tailored CoNiSe<sub>2</sub> Nanostructures as\nCoTe/CoNiSe<sub>2</sub> Hybrids Facilitating Bifunctional Behavior\nin Overall Water Splitting

Designing efficient, low cost, and stable electrocatalytic\nsystems\nto promote (oxygen evolution reaction) OER and (hydrogen evolution\nreaction) HER kinetics in the overall water splitting reaction is\na key constraint. Telluride- and selenide-based electrocatalytic systems\nare promising materials which facilitate H<sup>+</sup> adsorption\nonto active sites during the catalytic process in transition metal-based\nnanostructures. Herein, we developed a CoTe/CoNiSe<sub>2</sub> hybrid\nsystem to promote interfacial charge transfer between metallic and\nsemimetallic sites. The hybridized CoTe/CoNiSe<sub>2</sub> nanostructures,\n grown in situ on Ni-foam, comprised a higher catalytic response than\ntheir pristine counterparts. Low onset potential and high current\ndensity favors the hybridization approach for these Co- and Ni-based\ntelluride-selenide electrocatalysts. The decreased cell voltage potential\nof 1.40 and 1.43 V was observed in a two-electrode-based overall water\nsplitting cell, which favors their role as proficient catalytic materials.\nOverall water splitting effectiveness is markedly improved by the\nhybrid interface between CoTe and CoNiSe<sub>2</sub> because of greater\nelectron mobility and larger active surface area. This work makes\na substantial contribution to the catalysis field by presenting an\napproach for developing extremely efficient electrocatalysts.