Co3(hexahydroxytriphenylene)2: A conductive metal—organic framework for ambient electrocatalytic N2 reduction to NH3

As a carbon-neutral alternative to the Haber-Bosch process, electrochemical N2 reduction enables environment-friendly NH3 synthesis at ambient conditions but needs active electrocatalysts for the N2 reduction reaction. Here, we report that conductive metal—organic framework Co3(hexahydroxytriphenylene)2 (Co3HHTP2) nanoparticles act as an efficient catalyst for ambient electrochemical N2-to-NH3 fixation. When tested in 0.5 M LiClO4, such Co3HHTP2 achieves a large NH3 yield of 22.14 µg·h−1mg−1cat. with a faradaic efficiency of 3.34% at −0.40 V versus the reversible hydrogen electrode. This catalyst also shows high electrochemical stability and excellent selectivity toward NH3 synthesis.