Abstract
The broad employment of clean hydrogen through water electrolysis is restricted by large voltage requirement and energy consumption because of the sluggish anodic oxygen evolution reaction. Here we demonstrate a novel alternative oxidation reaction of green electrosynthesis of valuable 3,3'-diamino-4,4'-azofurazan energetic materials and coupled with hydrogen production. Such a strategy could greatly decrease the hazard from the traditional synthetic condition of 3,3'-diamino-4,4'-azofurazan and achieve low-cell-voltage hydrogen production on WS2/Pt single-atom/nanoparticle catalyst. The assembled two-electrode electrolyzer could reach 10 and 100 mA cm-2 with ultralow cell voltages of 1.26 and 1.55 V and electricity consumption of only 3.01 and 3.70 kWh per m3 of H2 in contrast of the conventional water electrolysis (~5 kWh per m3). Density functional theory calculations combine with experimental design decipher the synergistic effect in WS2/Pt for promoting Volmer-Tafel kinetic rate during alkaline hydrogen evolution reaction, while the oxidative-coupling of starting materials driven by free radical could be the underlying mechanism during the synthesis of 3,3'-diamino-4,4'-azofurazan. This work provides a promising avenue for the concurrent electrosynthesis of energetic materials and low-energy-consumption hydrogen production.