Consolidating the Immobilization of Tellurotungstate via Integrating with a Metal–Organic Framework for Electrocatalytic Hydrogen Evolution Performance in Alkaline/Seawater Medium

Polyoxotungstates, as a kind of polyoxometalate, show an advantage with high electrocatalytic activity for hydrogen evolution. Integrating polyoxotungstates with a metal-organic framework not only brings high stability in an aqueous environment but also tailors the distribution of active sites. In this work, four tellurotungstate-based coordination architectures are constructed based on the extension strategies toward nitrogen-rich organic ligands, including covalent modification and in situ transformation. The extended ligands are beneficial for constructing a metal-organic framework and immobilizing the tellurotungstate: The V-type interactions between the metal ion and N sites both reinforce the structure and extend the structure. In situ transformation for organic ligands from linear conformation to triangle expands the coordination direction and enhances the dimension. The specific immobilization of tellurotungstate brings more active sites and enhances the electrocatalytic activity. The carbon cloth-based electrode modified with TeW-4 can achieve a low overpotential of 17.0/34.7 mV at the catalytic current density of 10 mA cm⁻² for hydrogen evolution in 1 M KOH/simulated seawater and exhibit stable electrocatalytic stability.