Selective electroreduction of CO2 to acetone by single copper atoms anchored on N-doped porous carbon

Abstract

Efficient electroreduction of CO 2 to multi-carbon products is a challenging reaction because of the high energy barriers for CO 2 activation and CC coupling, which can be tuned by designing the metal centers and coordination environments of catalysts. Here, we design single atom copper encapsulated on N-doped porous carbon (Cu-SA/NPC) catalysts for reducing CO 2 to multi-carbon products. Acetone is identified as the major product with a Faradaic efficiency of 36.7% and a production rate of 336.1 μg h −1. Density functional theory (DFT) calculations reveal that the coordination of Cu with four pyrrole-N atoms is the main active site and reduces the reaction free energies required for CO 2 activation and CC coupling. The energetically favorable pathways for CH 3 COCH 3 production from CO 2 reduction are proposed and the origin of selective acetone formation on Cu-SA/NPC is clarified. This work provides insight into the rational design of efficient electrocatalysts for reducing CO 2 to multi-carbon products.

A Mn-N3 single-atom catalyst embedded in graphitic carbon nitride for efficient CO2 electroreduction

“…The coordination number of Mn in Mn–C 3 N 4 /CNT is 3.2, which is slightly different from that of the Mn–N 3 moiety. In general, it is accepted by researchers to use the integral value of the best-fitted coordination number to represent the structure of the catalyst active site in DFT calculations 38 , 39 , because there is an error bound while using the data from EXAFS to fit the coordination number. Therefore, a coordination number of three (Mn–N 3 ) is adopted as the catalyst structure for building a DFT model.…”

Single Cu Atoms as Catalysts for Efficient Hydrazine Oxidation Reaction

“…The 2p peak of P located at 133.7 eV was attributed to the P−N bonds (Figure S3b) . As shown in Figure S3c, the high‐resolution N 1s XPS spectrum was observed for five peaks at 398.3, 398.9, 400.1, 401.0, and 404.3 eV, which could be assigned to pyridinic‐N, Cu−N, pyrrolic‐N, graphitic‐N, and O−N, respectively . The C 1s XPS spectrum of Cu−SA/PCN suggests the existence of C−C (284.8 eV), C−NH 2 (286.3 eV), and N−C=N (288.0 eV) bonds …”

“…[45] As shown in Figure S3c, the high-resolution N 1s XPS spectrum was observed for five peaks at 398.3, 398.9, 400.1, 401.0, and 404.3 eV, which could be assigned to pyridinic-N, CuÀ N, pyrrolic-N, graphitic-N, and OÀ N, respectively. [46,47] The C 1s XPS spectrum of CuÀ SA/PCN suggests the existence of CÀ C (284.8 eV), CÀ NH 2 (286.3 eV), and NÀ C=N (288.0 eV) bonds. [48] The HzOR performances of the CuÀ SA/PCN were evaluated in a typical three-electrode configuration, wherein the Hg/HgO electrode and graphite rod are used as the reference and counter electrodes, respectively; further, an aqueous solution of 1 M KOH with different concentrations of hydrazine is used.…”

Towards the Large-Scale Electrochemical Reduction of Carbon Dioxide

“…The electrochemical conversion of CO2 constitutes a remarkable strategy for enabling negative carbon emission into the atmosphere, as it enables CO2 to be continuously converted into certain value-added chemicals. In addition, when a renewable energy source is used in the conversion, the carbon cycle can be eventually closed, thus providing potential substitutes for fossil fuels in the form of energy storage such as formate, methane, ethylene, CO, methanol, and acetone [2][3][4][5]. Moreover, in a large-scale operation, the production of these valued chemicals may satisfy the economic requirements and thus guarantee the sustainability of the technology.…”