Boron Nitride Quantum Dots/Ti3C2Tx‐MXene Heterostructure For Efficient Electrocatalytic Nitrogen Fixation

Electrocatalytic N 2 fixation through N 2 reduction reaction (NRR) has been regarded as a promising route for sustainable NH 3 synthesis, while exploring high‐performing NRR catalysts is pivotal yet challenging. Herein, BN quantum dots/Ti 3 C 2 T x ‐MXene (BNQDs/Ti 3 C 2 T x ) heterostructure is demonstrated as an efficient and durable NRR catalyst, exhibiting a high NH 3 yield of 52.8 ± 3.3 μg h −1 mg −1 with an FE of 19.1 ± 1.6% at −0.4 V (vs. RHE), which stand at the high level among all reported BN‐ and MXene‐based NRR catalysts. Theoretical computations reveal that the electronic interactions between BNQDs and Ti 3 C 2 T x enrich the electron density of B atoms at the heterointerface and endow them with enhanced electron‐donating capability for N 2 activation and protonation. Meanwhile, the decorated BNQDs can block the active sites of Ti 3 C 2 T x for hydrogen evolution, rendering a high N 2 ‐to‐NH 3 selectivity.