Cu₂O Nanoparticles Wrapped by N-Doped Carbon Nanotubes for Efficient Electroreduction of CO₂ to C₂ Products

Abstract

Electroreduction of carbon dioxide (CO 2 ) to C 2 products (ethylene and ethanol) using efficient catalysts is a feasible approach to alleviate the climate crisis. Cuprous oxide nanoparticles (Cu 2 O NPs) are a promising catalyst for C 2 production but suffer from inherent selectivity and durability. To address this challenge, a Cu 2 O NPs-nitrogen-doped carbon nanotube (Cu 2 O NPs-NCNT) composite was prepared with carbon nanotubes (CNTs), Cu 2 O NPs, and phthalocyanine (Pc). The results indicate that Cu 2 O NPs-NCNT has excellent Faradic efficiency of C 2 products (77.61%) at −1.1 V vs RHE, which is 103.43% higher than that of Cu 2 O NPs. In the potentiostatic electrolysis combined with Raman spectroscopy and X-ray photoelectron spectroscopy (XPS) measurements, Cu 2 O NPs-NCNT exhibited structural and catalytic current stability over 10 h. Finally, density functional theory calculations combined with XPS demonstrated that the NCNT in Cu 2 O NPs-NCNT can selectively absorb CO 2 through specific N−CO 2 interactions. Our work provides a unique strategy to promote the selectivity of Cu 2 O NPs for C 2 production by introducing N-doped linear carbon materials to fabricate composite.

Hollow carbon-based materials for electrocatalytic and thermocatalytic CO2 conversion

“… 162 Liu et al investigated the surface modification of N-doped CNTs on Cu 2 O NPs for enhanced CO 2 -to-C 2 electro-conversion. 160 The Cu 2 O NPs-NCNT sample showed a maximal C 2 (C 2 H 4 and C 2 H 5 OH) faradaic efficiency of 77.61% at −1.1 V vs. RHE, suppressing the value of the NCNT-free sample (Cu 2 O NPs, FEC 2 38.15%); noteworthily, the C 2 partial current density of Cu 2 O NPs-NCNT (16.79 mA cm −2 ) is 7.30 folds higher than that of Cu 2 O NPs (2.30 mA cm −2 ) at the same applied potential. It is proposed that NCNT is helpful for catalyzing the conversion of CO 2 to CO, which subsequently enriches the CO concentration at the heterogeneous interface of NCNT and Cu 2 O NPs and is conducive to C–C coupling to generate C 2 products.…”