Efficient Electron Transfer from an Electron‐Reservoir Polyoxometalate to Dual‐Metal‐Site Metal‐Organic Frameworks for Highly Efficient Electroreduction of Nitrogen

Abstract Precise design and construction of catalysts with satisfied performance for ambient electrolytic nitrogen reduction reaction (e‐NRR) is extremely challenging. By in situ integrating an electron‐rich polyoxometalates (POMs) into stable metal organic frameworks (MOFs), five POMs‐based MOFs formulated as [Fe x Co y (Pbpy) 9 (ox) 6 (H 2 O) 6 ][P 2 W 18 O 62 ]·3H 2 O (abbreviated as Fe x Co y MOF‐P 2 W 18 ) are created and directly used as catalysts for e‐NRR. Their electrocatalytic performances are remarkably improved thanks to complementary advantages and promising possibilities of MOFs and POMs. In particular, NH 3 yield rates of 47.04 µg h −1 mg cat. −1 and Faradaic efficiency of 31.56% by FeCoMOF‐P 2 W 18 for e‐NRR are significantly enhanced by a factor of 4 and 3, respectively, compared to the [Fe 0.5 Co 0.5 (Pbpy)(ox)] 2 ·(Pbpy) 0.5 . The cyclic voltammetry curves, density functional theory calculations and in situ Fourier‐transform infrared spectroscopy confirm that there is a directional electron channel from P 2 W 18 to the MOFs unit to accelerate the transfer of electrons. And the introduction of bimetals Fe and Co in the P 2 W 18 ‐based MOFs can reduce the energy of the *N 2 to *N 2 H step, thereby increasing the production of NH 3 . More importantly, this POM in situ embedding strategy can be extended to create other e‐NRR catalysts with enhanced performances, which opens a new avenue for future NH 3 production for breakthrough in the bottleneck of e‐NRR.