Enhanced Activity for CO₂ Electroreduction on a Highly Active and Stable Ternary Au-CDots-C₃N₄ Electrocatalyst

Abstract

Electrochemical reduction of CO2 to carbon-containing fuels possesses the potential to solve the environmental issues caused by excess CO2 in the atmosphere. Herein, we introduce a ternary Au-CDots-C3N4 electrocatalyst for efficiently reducing CO2 to CO. The ternary catalyst exhibited significantly enhanced activity and stability for CO2 electroreduction in comparison with pure Au NPs. The Au-CDots-C3N4 electrocatalyst demonstrates a high CO FE of ∼79.8% at −0.5 V and a 2.8-fold enhancement of current density (with the Au loading only 4 wt %) at −1.0 V relative to pure Au NPs. The DFT calculations and experimental observations indicate that the high activity toward CO2RR originates from the synergetic effect among Au NPs, CDots, and C3N4 and the capability of H+ and CO2 adsorption from CDots. The long-term stability tests demonstrate that the electrocatalyst can be used for over 8 h without obvious deactivations and maintained its activity over 60 days under normal conditions.

Constructing Conductive Interfaces between Nickel Oxide Nanocrystals and Polymer Carbon Nitride for Efficient Electrocatalytic Oxygen Evolution Reaction

“…The NiO/CN‐2:1, thus, possess more favorable stability than that of NiO/C and commercial RuO 2 . The improved stability over NiO/CN‐2:1 is due to the synergetic effects over NiO and CN in that the good mechanical strength of g‐C 3 N 4 can act as substrate to suppress NiO nanocrystallines aggregating and falling off from the glassy carbon electrode . The NiO/CN‐2:1 after OER test is also characterized by XRD as displayed in Figure S2 of the Supporting Information.…”

“…Some other factors also influenced the OER efficiency. For instance, the CN could act as substrate for dispersing NiO nanocrystals and prevent nanoparticles aggregating, which provided more active sites and promote the OER performance . The electrochemical active surface area (ESCA) was thus analyzed as shown in Figure S7a of the Supporting Information.…”

“…As a famous semiconductive polymer, polymer carbon nitride (generally known as g‐C 3 N 4 ) attracts extensive attention for its intriguing properties such as environmental‐friendly, low‐cost, elements earth‐abundant, and facile synthesis . Because of the chemical and mechanical stability as well as strong tolerance to acid and alkaline environments, carbon nitride materials (CN) are recently used as substrates for dispersing high conductive metal nanoparticles (e. g. Pd, Pt, and Cu) and graphene to reduce the particles aggregation during catalysis . However, CN composited with transition metal oxides for OER is seldom concerned.…”

Nitrogen‐Doped Graphene Quantum Dots Enhance the Activity of Bi2O3 Nanosheets for Electrochemical Reduction of CO2 in a Wide Negative Potential Region

“…Most of the Bi‐based catalysts for CO 2 reduction reported previously are the metallic bismuth (Bi 0 ), whereas there are fewer reports of bismuth oxide for electrochemical reduction of CO 2 in aqueous solution . On the other hand, carbon quantum dots are desirable for an important component of photo‐ and electro‐catalysts owing to their large number of exposed edge sites and excellent electronic properties . Furthermore, the surface of carbon quantum dots is easily functionalized by amino groups (−NH 2 ), which can increase the CO 2 adsorption ability efficiently .…”

Borophene: A Metal‐free and Metallic Electrocatalyst for Efficient Converting CO2 into CH4

“…[13] Previous studies have proved that nano-sized electrodes have better catalytic performance for ECRs than traditional bulk materials. [14] With the rapid development of nanotechnology, numerous nanomaterials from zero dimensional (0D) to three dimensional (3D), such as copper, [14,15] silver, [16] gold, [17] palladium nanostructures, [18] and metal/nonmetal doped nanomaterials, [19][20][21] have been successfully used as electrodes for ECR. Most of these studies are mainly focused on metalbased electrocatalysts.…”