Ionic Exchange of Metal–Organic Frameworks to Access Single Nickel Sites for Efficient Electroreduction of CO₂

Abstract

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.

Isolated Diatomic Ni‐Fe Metal–Nitrogen Sites for Synergistic Electroreduction of CO2

“…TheF e-doped ZIF-8 was first fabricated by mixing zinc nitrate,i ron nitrate,a nd 2-methylimidazole according to an established approach. [10] X-ray diffraction (XRD) analysis indicates that the crystal structure of the Fe and Ni co-doped precursors are similar to that of ZIF-8 ( Figure S3). TheF e-doped ZIF-8 was then dispersed in n-hexane uniformly,b efore as olution of nickel nitrate in methanol was added dropwise.…”

Isolated Square‐Planar Copper Center in Boron Imidazolate Nanocages for Photocatalytic Reduction of CO2 to CO

“…[1] Among these possible target products,the two-electron reduction of CO 2 to CO is al ess hindered process and plays an important role in the chemical industry. [9] Recent studies demonstrate that this type of catalyst exhibits high activity for reducing CO 2 to CO. [10] However, such ac atalyst is generally obtained through pyrolysis of Ni, or Co-based metal-organic frameworks (MOFs) or coordination polymers. Copper as an earth-abundant metal is ac ritical metal in photosynthesis [4] and Cu-based materials have been regarded as promising catalysts for efficiently photo-or electro-catalyzing CO 2 reduction.…”

“…[1a,2] To date,m uch research has been devoted to developing selective catalysts for reduction of CO 2 to CO. [3] Precious metals have been identified as promising candidates for CO 2 reduction to CO but their practical applications are still limited. [10,11] In contrast, no Cu-based catalysts with single active sites have been developed for the photocatalytic CO 2 reduction. [5] To date,v arious Cu-based catalysts have been developed but limited product selectivity due to the presence of multiple neighboring sites for involving CO 2 reduction.…”

Bifunctional Nitrogen and Cobalt Codoped Hollow Carbon for Electrochemical Syngas Production

“…Metal–organic frameworks (MOFs) have been demonstrated as excellent precursors or carriers for SAECs 6, 7, 8, 9, 10, 11, 12, 13. In contrast to conventional electrocatalyst in the form of foil, granule, or nanoparticle, SAEC not only brings down material cost in order of magnitude scale, but also displays intriguing physiochemical properties, allowing further manipulation of the activity and selectivity of electrocatalyts 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25.…”