Interfacial engineering of cobalt sulfide/graphene hybrids for highly efficient ammonia electrosynthesis

Significance Ammonia is one of the most important chemical raw materials with an annual production exceeding 200 million tons. The Haber–Bosch process is still the dominant route for industrial ammonia synthesis, which consumes 1∼3% of global annual energy production and represents a significant contributor to climate change. Electrocatalytic N 2 reduction reaction is an attractive alternative candidate for carbon-free and sustainable NH 3 production, but often suffers from low efficiency. Here, we developed an interfacial engineering strategy for preparing a class of strongly coupled hybrid electrocatalysts for N 2 fixation. The hybrids exhibit superior N 2 reduction reaction activity with a high NH 3 Faradaic efficiency of 25.9% under ambient conditions. This strategy provides an approach to design advanced materials for ammonia production.