The electrochemical synthesis of chemicals from carbon dioxide, which is an easily available and renewable carbon resource, is of great importance. However, to achieve high product selectivity for ...desirable C2 products like ethylene is a big challenge. Here we design Cu nanosheets with nanoscaled defects (2–14 nm) for the electrochemical production of ethylene from carbon dioxide. A high ethylene Faradaic efficiency of 83.2% is achieved. It is proved that the nanoscaled defects can enrich the reaction intermediates and hydroxyl ions on the electrocatalyst, thus promoting C–C coupling for ethylene formation.
Developing highly efficient electrocatalysts based on cheap and earth-abundant metals for CO
reduction is of great importance. Here we demonstrate that the electrocatalytic activity of ...manganese-based heterogeneous catalyst can be significantly improved through halogen and nitrogen dual-coordination to modulate the electronic structure of manganese atom. Such an electrocatalyst for CO
reduction exhibits a maximum CO faradaic efficiency of 97% and high current density of ~10 mA cm
at a low overpotential of 0.49 V. Moreover, the turnover frequency can reach 38347 h
at overpotential of 0.49 V, which is the highest among the reported heterogeneous electrocatalysts for CO
reduction. In situ X-ray absorption experiment and density-functional theory calculation reveal the modified electronic structure of the active manganese site, on which the free energy barrier for intermediate formation is greatly reduced, thus resulting in a great improvement of CO
reduction performance.
Electrochemical conversion of CO2 to valuable fuels is appealing for CO2 fixation and energy storage. The Cu‐based catalysts feature unique superiorities, but achieving high ethylene selectivity is ...still restricted. In this study, we propose the anchoring of an ionic liquid (IL) on a Cu electrocatalyst for improving the electrochemical CO2 reduction to ethylene. In a water‐based electrolyte and a commonly used H‐type cell, a high ethylene Faradaic efficiency of 77.3 % was achieved at −1.49 V (vs. RHE). Experimental and theoretical studies reveal that an IL can modify the electronic structure of a Cu catalyst through its interaction with Cu, making it more conducive to *CO dimerization for ethylene formation.
The ionic liquid 1‐butyl‐3‐methylimidazolium nitrate (BmimNO3) was anchored into Cu, through which the atomic coordination and electronic properties of Cu can be optimized to facilitate C−C coupling. This electrocatalyst can reduce CO2 to C2H4 with high selectivity. The Faradaic efficiency of C2H4 reaches 77.3 % at −1.49 V (vs. RHE) in KHCO3 aqueous solution using a H‐type cell, much higher than that over pure Cu catalyst (31.2 %).
It is of great importance to develop facile strategies to synthesize catalysts with desirable compositions and structures for high-performance photocatalytic hydrogen generation. In this work, we put ...forward an ionic liquid assisted one-pot route for the synthesis of heteroatom-doped Pt/TiO
2
composite material. This route is simple, environmentally benign and adjustable owing to the designable properties of ionic liquids. The as-synthesized Pt/TiO
2
nanocrystals exhibit high activity and stability for the photocatalytic hydrogen generation under simulated solar irradiation. This method can be easily applied to the synthesis of various kinds of metal/TiO
2
composites doped with desirable heteroatoms (e.g., F, Cl, Br, etc).
UiO-66-NH2, an important metal–organic framework, is usually synthesized by solvothermal method and the particle size is generally larger than 200 nm, which limits its catalytic applications in ...chemical reactions. It is very meaningful to produce UiO-66-NH2 nanoparticles with ultra-small size, but remains challenging. Herein, we synthesized UiO-66-NH2 nanoparticles in size of 8–15 nm that are immobilized on g-C3N4 nanosheets. Compared with the UiO-66-NH2 synthesized by the traditional solvothermal method (> 200 nm), the ultra-small UiO-66-NH2 nanoparticles immobilized on g-C3N4 have more unsaturated coordination positions and increased Lewis acidity. Owing to these combined advantages, the ultra-small UiO-66-NH2 nanoparticles exhibit greatly improved catalytic activity for Meerwein–Ponndorf–Verley reaction than larger UiO-66-NH2 particles.
Herein, we synthesized UiO-66-NH2 nanoparticles in size of 8–15 nm that are immobilized on g-C3N4 nanosheets. Compared with the UiO-66-NH2 micronparticles (~0.2 μm), the ultra-small UiO-66-NH2 nanoparticles exhibit high catalytic activity for Meerwein–Ponndorf–Verley reaction owing to more unsaturated coordination positions and increased Lewis acidity. Display omitted
To improve the electrocatalytic transformation of carbon dioxide (CO2) to multi-carbon (C2+) products is of great importance. Here we developed a nitrogen-doped Cu catalyst, by which the maximum C2+ ...Faradaic efficiency can reach 72.7% in flow-cell system, with the partial current density reaching 0.62 A cm−2. The in situ Raman spectra demonstrate that the ∗CO adsorption can be strengthened on such a N-doped Cu catalyst, thus promoting the ∗CO utilization in the subsequent C–C coupling step. Simultaneously, the water activation can be well enhanced by N doping on Cu catalyst. Owing to the synergistic effects, the selectivity and activity for C2+ products over the N-deoped Cu catalyst are much improved.
N-doped Cu exhibited remarkable efficiency in the electrocatalytic conversion of CO2-to-C2+ products. At a high current density of 0.85 A cm−2, the Faradaic efficiency of C2+ products reached 72.7%. This exceptional catalyst performance can primarily come from the improved ∗CO utilization and H2O activation by N doping. Display omitted
•N-doped Cu showed a good electrocatalytic performance in converting CO2 to for multi-carbon products.•The N-doped Cu catalyst was synthesized by a electrolyis route for Cu3N precatalyst.•The performance improvement originates from the enhanced ∗CO utilization and H2O activation by N doping.
The acidic electrocatalytic conversion of CO2 to multi‐carbon (C2+) oxygenates is of great importance in view of enhancing carbon utilization efficiency and generating products with high energy ...densities, but suffering from low selectivity and activity. Herein, we synthesized Ag‐Cu alloy catalyst with highly rough surface, by which the selectivity to C2+ oxygenates can be greatly improved. In a strongly acidic condition (pH=0.75), the maximum C2+ products Faradaic efficiency (FE) and C2+ oxygenates FE reach 80.4% and 56.5% at ‐1.9 V versus reversible hydrogen electrode, respectively, with a ratio of FEC2+ oxygenates to FEethylene up to 2.36. At this condition, the C2+ oxygenates partial current density is as high as 480 mA cm‐2. The in situ Raman measurements and control experiments indicate that the high generation of C2+ oxygenates over the catalyst originates from its large surface roughness and Ag alloying.
Electrochemical conversion of CO2 to chemicals is an appealing route to reduce carbon emission and achieve carbon neutrality. Indium (In) is a promising electrocatalyst for CO2-to-formate conversion ...due to its high selectivity to formate, but is still hindered by low current density and poor stability. In this work, we propose the construction of In nanotubes from MIL-68(In) metal-organic framework nanotubes by a electrolytic route, which is simple, rapid and low-cost. Benefiting from the nanotube morphology and abundant unsaturated coordination In sites, the as-synthesized In nanotubes exhibit high performance for the electrochemical CO2-to-formate conversion. The formate Faradaic efficiency can reach 98.6% at −1.2 V versus reversible hydrogen electrode by using 0.5 M KHCO3 aqueous solution as electrolyte in H-cell, with current density of 24.8 mA cm−2.
We demonstrate the construction of Indium (In) nanotubes that possess abundant unsaturated coordination In sites, derived from MIL-68(In) by a rapid electrolytic route (30 min). The In nanotubes exhibit high performance for electrocatalytic CO2-to-formate conversion. The maximum formate Faradaic efficiency reaches 98.6% at −1.2 V versus reversible hydrogen electrode in H-cell, with current density of 24.8 mA cm−2. Display omitted
•Indium nanotubes were synthesized by electrolysis for metal-organic framework.•Indium nanotubes possess abundant unsaturated coordination active sites.•Indium nanotubes show high activity for carbon dioxide electroreduction to formate.
Electrochemical conversion of CO
to valuable fuels is appealing for CO
fixation and energy storage. The Cu-based catalysts feature unique superiorities, but achieving high ethylene selectivity is ...still restricted. In this study, we propose the anchoring of an ionic liquid (IL) on a Cu electrocatalyst for improving the electrochemical CO
reduction to ethylene. In a water-based electrolyte and a commonly used H-type cell, a high ethylene Faradaic efficiency of 77.3 % was achieved at -1.49 V (vs. RHE). Experimental and theoretical studies reveal that an IL can modify the electronic structure of a Cu catalyst through its interaction with Cu, making it more conducive to *CO dimerization for ethylene formation.
To develop high-performance metal-organic frameworks (MOFs) for catalysis is of great importance. Here, we synthesized the mesoporous Cu
3−
x
Zn
x
(BTC)
2
(BTC = benzene-1,3,5-tricarboxylate) ...nanocubes in a deep eutectic solvent of ZnCl
2
/ethylene glycol solution. The route can proceed at room temperature and the reaction time needed is shortened to be 30 min, which is superior to the conventional solvothermal route that usually needs high temperature and long reaction time. The formation mechanism of the mesoporous Cu
3−
x
Zn
x
(BTC)
2
nanocubes in deep eutectic solvent (DES) was investigated by
in situ
synchrotron X-ray diffraction/small angle X-ray scattering/X-ray absorption fine structure conjunction technique. The mesoporous Cu
3−
x
Zn
x
(BTC)
2
nanocubes exhibit high catalytic activity and reusability for cyanosilylation reaction of benzaldehyde and aerobic oxidation reaction of benzylic alcohol.
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