LAUSR

Hydrogen evolution reaction (HER) via electrochemical water-splitting is one of the thrust areas of energy research and benchmark electrocatalysts used for this reaction are based on expensive noble metals. This is a major bottleneck for their large-scale operation. Thus, development of efficient metal-free electrocatalysts is very demanding for sustainable and economical production of the renewable fuel hydrogen via water-splitting reaction. Covalent organic frameworks (COFs) can offer valuable advancement on this matter by virtue of their architectural stability, nanoscale porosity, abundant active sites located periodically in the entire framework, and high electronic conduction due to extended π-delocalization. In this work, we report a new COF material C 6 -TRZ-TFP synthesized via solvothermal polycondensation reaction of 2-hydroxybenzene-1,3,5-tricarbaldehyde (TFP) and 4,4',4''-(1,3,5-triazine-2,4,6-triyl)tris([1,1'-biphenyl]-4-amine). C 6 -TRZ-TFP COF displayed excellent HER activity in the electrochemical water-splitting with a very low overpotential of 200 mV and specific activity of 0.2831 mA/cm 2 together with high retention in the catalytic activity after a longer duration of electrocatalysis of the aqueous solution of 0.5M H 2 SO 4 . The density functional theory (DFT) calculations suggest that the electron deficient carbon sites near the π electron-donating nitrogen atoms are more active towards HER than carbon sites near the electron-withdrawing nitrogen and oxygen atoms.