Unveiling the Synergistic Effect between Graphitic Carbon Nitride and Cu₂O toward CO₂Electroreduction to C₂H₄

Abstract

Electrochemically reducing carbon dioxide (CO2RR) to ethylene is one of the most promising strategies to reduce carbon dioxide emissions and simultaneously produce high value‐added chemicals. However, the lack of catalysts with excellent activity and stability limits the large‐scale application of this technology. In this work, a graphitic carbon nitride (g‐C3N4)‐supported Cu2O composite was fabricated, which exhibited a 32.2 % faradaic efficiency of C2H4 with a partial current density of −4.3 mA cm−2 at −1.1 V vs. reversible hydrogen electrode in 0.1 m KHCO3 electrolyte. The introduction of g‐C3N4 support not only enhanced the uniform dispersion of Cu2O nanocubes, but also stabilized the important *CO intermediates. Moreover, the g‐C3N4 itself had a good activity of reducing CO2 to form *CO, which enriched the key intermediates of C−C coupling around cuprous oxide. The findings highlight the importance of the g‐C3N4 support, a unique two‐dimensional material, including not only the strong CO2 adsorption and activation capacity but also its synergistic effect with the cuprous oxide in CO2RR selectivity.

Anchoring Ionic Liquid in Copper Electrocatalyst for Improving CO2 Conversion to Ethylene

“…Great efforts have been devoted to the development of electrocatalysts for improving C 2 H 4 production from CO 2 RR, including crystal plane adjustment, [4,5] defect engineering, [6] alloying, [7][8][9] valence regulation [10] and surface molecule modification. [11][12][13] Among the cathode metals applied, Cu has been the predominant electrocatalytic material. At present, the highest Faradaic efficiency (FE) of C 2 H 4 is 87 % at À 0.47 V versus the reversible hydrogen electrode (vs. RHE), which was achieved by a Cu-polyamine hybrid catalyst conducting in a flow reactor, with a gas diffusion layer as cathode.…”

Amino Modified Carbon Dots with Electron Sink Effect Increase Interface Charge Transfer Rate of Cu‐Based Electrocatalyst to Enhance the CO2 Conversion Selectivity to C2H4

“…[10,11] In order to improve the selectivity of C 2 products, promoting CC coupling on the interface of Cu-based material is an effective strategy to promote the ratedetermining step of *CO dimerization to C 2 products. [12][13][14] A series of strategies such as adjusting the crystal surface structure, [15][16][17][18] generating structural defects and vacancies, [19] adjusting the relationship with the carrier, [20][21][22] and doping [23,24] have been widely reported. However, it is seldom exploited to obtain higher catalytic selectivity by adjusting the electron transport behavior at the interface of Cu-based catalysts, which is also a step that cannot be ignored during the catalytic process.…”

A Cu2O‐derived Polymeric Carbon Nitride Heterostructured Catalyst for the Electrochemical Reduction of Carbon Dioxide to Ethylene

“…We proposed that the high activity and high selectivity of the Cu x O/CN‐10 heterostructured catalyst originate from the interactions between Cu x O and the CN film. Many articles have also proved this assumption through DFT calculations and experiments [28,47,49] . Furthermore, we used a simple and cost‐effective preparation method to synthesize a series of Cu x O/CN catalysts and accurately control the thickness of the CN film covering the Cu x O active sites.…”

“…In addition, two additional CO 2 ‐desorption peaks at 349 and 432 °C were observed on Cu x O/CN‐10, indicating the existence of metal‐oxygen pairs (Cu−O) [46] . The higher‐temperature CO 2 ‐desorption peaks demonstrated that the CN film increased the charge density of Cu x O active sites, and improved the chemisorption ability of CO 2 [47] …”