Single-atom catalysts often exhibit unexpected catalytic activity for many important chemical reactions because of their unique electronic and geometric structures with respect to their bulk counterparts. Herein we adopt metal-organic frameworks (MOFs) to assist the preparation of a catalyst containing single Ni sites for efficient electroreduction of CO. The synthesis is based on ionic exchange between Zn nodes and adsorbed Ni ions within the cavities of the MOF. This single-atom catalyst exhibited an excellent turnover frequency for electroreduction of CO (5273 h), with a Faradaic efficiency for CO production of over 71.9% and a current density of 10.48 mA cm at an overpotential of 0.89 V. Our findings present some guidelines for the rational design and accurate modulation of nanostructured catalysts at the atomic scale.

We prepared single Ni atoms embedded in an N-doped carbon catalyst with the assistance of metal organic frameworks. The dispersion of Ni atoms was verified by taking X-ray absorption fine structure measurements. Under the typical conditions for hydrogenation of acetylene, this single-site heterogeneous catalyst showed great potential as an alternative to Pd-based materials.