Highly Efficient Electroreduction of CO₂ to C2+ Alcohols on Heterogeneous Dual Active Sites

Abstract

Electroreduction of CO2 to liquid fuels such as ethanol and n‐propanol, powered by renewable electricity, offers a promising strategy for controlling the global carbon balance and addressing the need for the storage of intermittent renewable energy. In this work, we discovered that the composite composed of nitrogen‐doped graphene quantum dots (NGQ) on CuO‐derived Cu nanorods (NGQ/Cu‐nr) was an outstanding electrocatalyst for the reduction of CO2 to ethanol and n‐propanol. The Faradaic efficiency (FE) of C2+ alcohols could reach 52.4 % with a total current density of 282.1 mA cm−2. This is the highest FE for C2+ alcohols with a commercial current density to date. Control experiments and DFT studies show that the NGQ/Cu‐nr could provide dual catalytic active sites and could stabilize the CH2CHO intermediate to enhance the FE of alcohols significantly through further carbon protonation. The NGQ and Cu‐nr had excellent synergistic effects for accelerating the reduction of CO2 to alcohols.

Enhanced Ethylene Formation from Carbon Dioxide Reduction through Sequential Catalysis on Au Decorated Cubic Cu2O Electrocatalyst

“…[61] Furthermore, the product selectivity of Au x Cu 2 O were examined between À 0.9 V and À 1. [48,[62][63] As shown in Figure 5c-e O catalysts, which was in agreement with the result of previously reported oxygen-Cu combination catalysts. [11,41] Their results indicated the selectivity of C 2 H 4 to CH 4 in OÀ Cu combination catalysts was influenced by the electrochemical reduction environment related to the mixed valences.…”

“…This was consistent with the selectivity of C 2 products (C 2 H 4 or C 2 H 5 OH) on the NGQ/Cu-NR, Cu x Zn and Au/Cu catalysts in previous reports. [12,24,48,59,63] Since the above results clearly approved the importance of introduced Au atoms in increasing CO formation, it was necessary to discuss the effect of copper states on C 2 H 4 formation. The above XRD and XPS characterizations have confirmed the co-existence of Cu + and Cu 0 states in the Au x Cu 2 O catalyst after LSV reduction.…”

Efficient electroreduction of CO2to C2+products on CeO2modified CuO

“…The electrocatalytic performance of the catalysts was evaluated in the ow cell and 1 M KOH was used as the electrolyte, as reported in our previous work. 51 Before the CO 2 RR, the catalysts were rstly reduced around À0.3 V vs. RHE, which is more negative than the transformation of CuO to Cu (Fig. S3 †).…”

The in situ study of surface species and structures of oxide-derived copper catalysts for electrochemical CO2 reduction

“…The electrocatalytic performance of the catalysts were evaluated in a flow cell, as reported in our previous work. 40 The gas chromatography (GC) and nuclear magnetic resonance (NMR) spectroscopy were used to analyze the gaseous and liquid products, respectively ( Figure S8 and S9). For Cu-nr, the FE of C2+ products (FE C2+ ) was 64.6% at -0.9 V vs. RHE ( Figure 2A).…”