Surface-immobilized cross-linked cationic polyelectrolyte enables CO2 reduction with metal cation-free acidic electrolyte

Nature Communications, Год журнала: 2023, Номер 14(1)

Опубликована: Сен. 13, 2023

Electrochemical CO2 reduction in acidic electrolytes is a promising strategy to achieve high utilization efficiency of CO2. Although alkali cations play vital role suppressing hydrogen evolution and promoting reduction, they also cause precipitation bicarbonate on the gas diffusion electrode (GDE), flooding electrolyte through GDE, drift pH. In this work, we realize electroreduction metal cation-free by covering catalyst with cross-linked poly-diallyldimethylammonium chloride. This polyelectrolyte provides density cationic sites immobilized surface catalyst, which suppresses mass transport H+ modulates interfacial field strength. By adopting strategy, Faradaic (FE) CO reaches 95 ± 3% Ag FE formic acid 76 1.0 pH flow cell. More importantly, amount GDE decreased 2.5 0.6% that cation-containing electrolyte, maintains above 80% over 36 h operation at -200 mA·cm-2.

Язык: Английский

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Reaction Environment Regulation for Electrocatalytic CO₂ Reduction in Acids

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(26)

Опубликована: Апрель 19, 2024

The electrocatalytic CO

Язык: Английский

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Nanocurvature-induced field effects enable control over the activity of single-atom electrocatalysts

Nature Communications, Год журнала: 2024, Номер 15(1)

Опубликована: Фев. 26, 2024

Tuning interfacial electric fields provides a powerful means to control electrocatalyst activity. Importantly, can modify adsorbate binding energies based on their polarizability and dipole moment, hence operate independently of scaling relations that fundamentally limit performance. However, implementation such strategy remains challenging because typical methods the field non-uniformly affects only minority active sites. Here we discover uniformly tunable modulation be achieved using model system single-atom catalysts (SACs). These consist M-N

Язык: Английский

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Interfacial Water Tuning by Intermolecular Spacing for Stable CO₂ Electroreduction to C₂₊ Products

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(43)

Опубликована: Сен. 7, 2023

Electroreduction of CO2 to multi-carbon (C2+ ) products is a promising approach for utilization renewable energy, in which the interfacial water quantity critical both C2+ product selectivity and stability Cu-based electrocatalytic sites. Functionalization long-chain alkyl molecules on catalyst surface can help increase its stability, while it also tends block transport water, thus inhibiting formation. Herein, we demonstrate fine tuning by assembly toluene Cu nanosheets, allowing sustained enriched supply but retarded transfer catalytic surface. Compared bare with fast cathodic corrosion alkyl-modified main CO product, nanosheet enabled high Faradaic efficiency 78 % partial current density 1.81 A cm-2 . The toluene-modified further exhibited highly stable -to-C2 H4 conversion 400 h membrane-electrode-assembly electrolyzer, suggesting attractive feature efficient excellent stability.

Язык: Английский

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Unveiling pH‐Dependent Adsorption Strength of *CO₂⁻ Intermediate over High‐Density Sn Single Atom Catalyst for Acidic CO₂‐to‐HCOOH Electroreduction

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(14)

Опубликована: Фев. 16, 2024

Abstract The acidic electrochemical CO 2 reduction reaction (CO RR) for direct formic acid (HCOOH) production holds promise in meeting the carbon‐neutral target, yet its performance is hindered by competing hydrogen evolution (HER). Understanding adsorption strength of key intermediates electrolyte indispensable to favor RR over HER. In this work, high‐density Sn single atom catalysts (SACs) were prepared and used as catalyst, reveal pH‐dependent coverage *CO − intermediatethat enables enhanced towards HCOOH production. At pH=3, SACs could deliver a high Faradaic efficiency (90.8 %) formation corresponding partial current density up −178.5 mA cm −2 . detailed situ attenuated total reflection Fourier transform infrared (ATR‐FTIR) spectroscopic studies that favorable alkaline microenvironment formed near surface SACs, even electrolyte. More importantly, intermediate unravelled which turn affects competition between HER

Язык: Английский

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Continuously Producing Highly Concentrated and Pure Acetic Acid Aqueous Solution via Direct Electroreduction of CO₂

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(1), С. 1144 - 1152

Опубликована: Янв. 2, 2024

It is crucial to achieve continuous production of highly concentrated and pure C2 chemicals through the electrochemical CO2 reduction reaction (eCO2RR) for artificial carbon cycling, yet it has remained unattainable until now. Despite one-pot tandem catalysis (dividing eCO2RR into two catalytical reactions CO C2) offering potential significantly enhancing efficiency, its mechanism remains unclear performance unsatisfactory. Herein, we selected different CO2-to-CO catalysts CO-to-acetate construct several catalytic systems acetic acid. Among them, a system comprising covalent organic framework (PcNi-DMTP) metal–organic (MAF-2) as catalysts, respectively, exhibited faradaic efficiency 51.2% with current density 410 mA cm–2 an ultrahigh acetate yield rate 2.72 mmol m–2 s–1 under neutral conditions. After electrolysis 200 h, 1 working electrode can continuously produce 20 mM acid aqueous solution relative purity 95+%. Comprehensive studies revealed that influenced not only by supply–demand relationship electron competition between processes in but also CO-to-C2 catalyst diluted

Язык: Английский

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CO2 fixation into carbon nanofibres using electrochemical–thermochemical tandem catalysis

Nature Catalysis, Год журнала: 2024, Номер 7(1), С. 98 - 109

Опубликована: Янв. 11, 2024

Язык: Английский

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Immobilized Tetraalkylammonium Cations Enable Metal‐free CO₂ Electroreduction in Acid and Pure Water

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(9)

Опубликована: Янв. 2, 2024

Abstract Carbon dioxide reduction reaction (CO 2 RR) provides an efficient pathway to convert CO into desirable products, yet its commercialization is greatly hindered by the huge energy cost due loss and regeneration. Performing RR under acidic conditions containing alkali cations can potentially address issue, but still causes (bi)carbonate deposition at high current densities, compromising product Faradaic efficiencies (FEs) in present‐day acid‐fed membrane electrode assemblies. Herein, we present a strategy using positively charged polyelectrolyte—poly(diallyldimethylammonium) immobilized on graphene oxide via electrostatic interactions displace cations. This enables FE of 85 %, carbon efficiency 93 (EE) 35 % for 100 mA cm −2 modified Ag catalysts acid. In pure‐water‐fed reactor, obtained 78 with 30 EE 40 °C. All performance metrics are comparable or even exceed those attained presence metal

Язык: Английский

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Materials challenges on the path to gigatonne CO2 electrolysis

Nature Reviews Materials, Год журнала: 2024, Номер 9(8), С. 535 - 549

Опубликована: Июнь 24, 2024

Язык: Английский

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A covalent molecular design enabling efficient CO2 reduction in strong acids

Nature Synthesis, Год журнала: 2024, Номер 3(10), С. 1231 - 1242

Опубликована: Июнь 25, 2024

Язык: Английский

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