Green N-N oxidative coupling synthesis of energetic compounds and energy-saving hydrogen evolution reaction

The electrochemical water splitting process is comprised of hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), where the OER is usually the bottleneck of the whole reaction, causing the high overpotential, while the oxidation product (O2) is of less economic value. In this article, we report a new coupling system based on the green electro-oxidation synthesis of energetic compounds and simultaneous H2 production on the molybdenum disulfide/ruthenium-based single-atom catalyst (Ru SAs MoS2/CC). The charge redistribution and synergistic interaction between MoS2 and Ru SAs for alkaline HER were systemically investigated by experimental and density functional theory (DFT) calculation. More importantly, the integration of overall water splitting (OWS) and anodic N-N oxidative coupling of 5-amino-1H-tetrazole (5-AT) shows an ultralow cell voltage of 1.36 V at 10 mA cm−2 for the H2 production and simultaneously realize green-synthesis of dipotassium 5,5′-azotetrazole (K2AZT), which is traditionally synthesized under harsh condition requiring high temperature and excessive oxidant. This work highlights a unique strategy for energy-saving H2 production and eco-friendly electrosynthesis of energetic compounds.