Pd(II) functionalized vinylene-linked covalent organic frameworks for acidic electrocatalytic hydrogen evolution reaction

The development of non-platinum-based electrocatalysts for hydrogen evolution reaction (HER) is always a meaningful and hot research issue as it is an effective and promising route to produce clean hydrogen energy and alleviate the energy crisis. Herein, a vinylene-linked covalent organic framework (PY-SE-COF) was constructed by Knoevenagel reaction and served as palladium ions (Pd2+) supports with Pd content of 16.8 wt%. PY-SE–COF–Pd can be applied as an efficient electrocatalyst for hydrogen evolution reaction (HER) in acidic electrolyte with an overpotential of 128 mV at the current density of 10 mA cm−2, outperforming the electrocatalytic activity of individual PY-SE-COF and PdCl2. This is the first Pd2+ coordinated COFs electrocatalytic system for HER and the current study proves that vinylene-linked COFs are promising platforms for the design and construction of composite pyrolysis-free electrocatalysts for clean energy conversion.