Boosting Electrochemical Carbon Dioxide Reduction on Atomically Dispersed Nickel Catalyst

Abstract

Single-atom catalysts (SACs) with metal–nitrogen (M–N) sites are one of the most promising electrocatalysts for electrochemical carbon dioxide reduction (ECO2R). However, challenges in simultaneously enhancing the activity and selectivity greatly limit the efficiency of ECO2R due to the improper interaction of reactants/intermediates on these catalytic sites. Herein, we report a carbon-based nickel (Ni) cluster catalyst containing both single-atom and cluster sites (NiNx-T, T = 500–800) through a ligand-mediated method and realize a highly active and selective electrocatalytic CO2R process. The catalytic performance can be regulated by the dispersion of Ni–N species via controlling the pyrolysis condition. Benefitting from the synergistic effect of pyrrolic-nitrogen coordinated Ni single-atom and cluster sites, NiNx-600 exhibits a satisfying catalytic performance, including a high partial current density of 61.85 mA cm−2 and a high turnover frequency (TOF) of 7,291 h−1 at −1.2 V vs. RHE, and almost 100% selectivity toward carbon monoxide (CO) production, as well as good stability under 10 h of continuous electrolysis. This work discloses the significant role of regulating the coordination environment of the transition metal sites and the synergistic effect between the isolated single-site and cluster site in enhancing the ECO2R performance.

Single atomic Fe–N4 active sites and neighboring graphitic nitrogen for efficient and stable electrochemical CO2 reduction

“…The decrease in the Fe species content can be attributed to the volatilization of metal species during high-temperature pyrolysis. 55 Additionally, the content of graphitic N increases with pyrolysis temperature, while the contents of pyridinic and pyrrolic N decrease significantly. However, this can be related to the increment of graphitization degree caused by the high-temperature annealing and post-synthesis acid treatment, during which both pyrrolic and pyridinic N were converted to thermodynamically more stable graphitic N. Further, the increased intensity of π–π* in XPS of C 1s peak confirms the increase in the degree of graphitization (Fig.…”

Fractal growth of a fern-like nanostructured Cu2O film electrode for electrochemical reduction of CO2 to ethanol

“…S4†). 67–71 It is noted that there is a direct correlation between the applied potential and the current measured. The chronoamperometry measurements performed for 1 hour on each electrode at given potentials show the current in the range of 0.5 to 10 mA cm −2 .…”

Commercial Anion Exchange Membranes (AEMs) for Fuel Cell and Water Electrolyzer Applications: Performance, Durability, and Materials Advancement

“…Specifically, these membranes have demonstrated their suitability in electrochemical CO 2 reduction applications where the electrolyte solutions typically consist of 0.1 to 0.5 M KOH or NaOH, as well as solutions containing 0.1 to 0.5 M water-soluble carbonate or bicarbonate salts. These membranes offer flexibility in terms of their application, allowing researchers to explore various experimental setups and conditions to achieve efficient CO 2 reduction [64][65][66]. Moreover, their versatility extends beyond CO 2 reduction to encompass other electrochemical processes such as electrodialysis, desalination, reverse electrodialysis, and acid recovery [67][68][69][70].…”