An Undergraduate Laboratory Module Using a Ternary Nitride Electrocatalyst to Teach Structure–Property Relationships in Electrocatalytic Hydrogen Evolution

The hydrogen evolution reaction (HER) in alkaline media is central to sustainable hydrogen production but is limited by sluggish kinetics and catalyst instability. To connect fundamental chemistry, electrochemistry, and materials science with hands-on learning, we designed a laboratory experiment for undergraduate students to synthesize and evaluate a Mo 3 N 2 /Ni 3 Mo 3 N/Co 3 Mo 3 N triple-phase nitride electrocatalyst, composed of three integrated nitride phases. The ternary structure provides abundant active sites and efficient charge-transfer interfaces, which achieve a low overpotential of 33 mV at 10 mA cm –2, surpassing binary analogues and approaching the HER performance of the benchmark platinum-on-carbon (Pt/C) electrocatalyst. Students prepare working electrodes, characterize catalyst structure using X-ray diffraction and electron microscopy, and perform electrochemical HER measurements. Analysis of polarization curves, Tafel plots, electrochemical impedance spectroscopy data, and electrochemically active surface area, combined with guided comparisons between ternary and binary systems, enables students to relate structural features to the HER activity. This integrated approach demonstrates how multiphase design enhances HER activity, offering students insights into rational electrocatalyst design and sustainable energy research.