In-situ spectroscopic probe of the intrinsic structure feature of single-atom center in electrochemical CO/CO2 reduction to methanol

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

Опубликована: Июнь 9, 2023

While exploring the process of CO/CO2 electroreduction (COxRR) is great significance to achieve carbon recycling, deciphering reaction mechanisms so as further design catalytic systems able overcome sluggish kinetics remains challenging. In this work, a model single-Co-atom catalyst with well-defined coordination structure developed and employed platform unravel underlying mechanism COxRR. The as-prepared exhibits maximum methanol Faradaic efficiency high 65% at 30 mA/cm2 in membrane electrode assembly electrolyzer, while on contrary, reduction pathway CO2 strongly decreased CO2RR. In-situ X-ray absorption Fourier-transform infrared spectroscopies point different adsorption configuration *CO intermediate CORR compared that CO2RR, weaker stretching vibration C-O bond former case. Theoretical calculations evidence low energy barrier for formation H-CoPc-CO- species, which critical factor promoting electrochemical CO methanol.

Язык: Английский

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Green transformation of CO₂ to ethanol using water and sunlight by the combined effect of naturally abundant red phosphorus and Bi₂MoO₆

Energy & Environmental Science, Год журнала: 2022, Номер 15(5), С. 1967 - 1976

Опубликована: Янв. 1, 2022

A novel type-II composite heterostructure obtained by combining earth-abundant, non-toxic, cost-effective red phosphorus and Bi 2 MoO 6 selectively converts CO to ethanol using sunlight water.

Язык: Английский

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Nickel polyphthalocyanine with electronic localization at the nickel site for enhanced CO2 reduction reaction

Applied Catalysis B Environment and Energy, Год журнала: 2022, Номер 306, С. 121093 - 121093

Опубликована: Янв. 13, 2022

Nickel phthalocyanine (NiPc) can be at first glance a compelling catalyst for CO2 reduction reaction (CO2RR) because of its Ni–N4 site. Unfortunately, the pristine NiPc possesses low catalytic activity resulting from poor adsorption and activation capabilities electron-deficiency Ni Herein, we develop nickel polyphthalocyanine (NiPPc) with extended conjugation to tailor electronic density active The enlarged π NiPPc evokes d-electrons localization, increasing site, which enhances activation. Consequently, supported on carbon nanotubes (NiPPc/CNT) in flow cell delivers an excellent −300 mA cm−2 CO2RR CO selectivity 99.8%, is much higher than that dispersed nanotubes. NiPPc/CNT exhibits outstanding stability more 30 h current −100 ultrahigh CO, exceeding 99.7%. This work showcases new way tuning sites.

Язык: Английский

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Reactive Capture of CO₂: Opportunities and Challenges

ACS Catalysis, Год журнала: 2022, Номер 13(1), С. 766 - 784

Опубликована: Дек. 27, 2022

Reactive capture of CO2 (RCC) refers to the process integration with conversion captured into a product. The RCC approach does not include step where is released (thermally) from agent and thus has potential provide significant energy savings relative traditional release processes. This Perspective highlights just selection prior contributions chemistry, thermal RCC, electrochemically driven RCC. Opportunities reduction are highlighted, challenges for future development mentioned. will require multidisciplinary across industry, chemical engineering, advanced manufacturing, this was written view bridge some these areas.

Язык: Английский

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Zero-Gap Bipolar Membrane Electrolyzer for Carbon Dioxide Reduction Using Acid-Tolerant Molecular Electrocatalysts

Journal of the American Chemical Society, Год журнала: 2022, Номер 144(17), С. 7551 - 7556

Опубликована: Апрель 22, 2022

The scaling-up of electrochemical CO2 reduction requires circumventing the loss as carbonates under alkaline conditions. Zero-gap cell configurations with a reverse-bias bipolar membrane (BPM) represent possible solution, but catalyst layer in direct contact acidic environment BPM usually leads to H2 evolution dominating. Here we show that using acid-tolerant Ni molecular electrocatalysts selective (>60%) can be achieved zero-gap device pure water and feed. At higher current density (100 mA cm-2), CO selectivity decreases, was still >30%, due reversible product inhibition. This study demonstrates importance developing catalysts for use large-scale devices.

Язык: Английский

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CO₂ Electrolysis System under Industrially Relevant Conditions

Accounts of Chemical Research, Год журнала: 2022, Номер 55(3), С. 231 - 240

Опубликована: Янв. 19, 2022

ConspectusCarbon dioxide emissions from consumption of fossil fuels have caused serious climate issues. Rapid deployment new energies makes renewable energy driven CO2 electroreduction to chemical feedstocks and carbon-neutral a feasible cost-effective pathway for achieving net-zero emission. With the urgency goal, we initiated our research on electrolysis with emphasis industrial relevance.The molecules are thermodynamically stable due high activation two C═O bonds, efficient electrocatalysts required overcome sluggish dynamics competitive hydrogen evolution reaction. The that explored include molecular catalysts nanostructured catalysts. Molecular centered earth abundant elements such as Fe Co catalyzing reduction, using catalysts, proposed an amidation strategy reduction methanol, bypassing inactive formate pathway. For developed carbon enrichment nitrogen-rich nanomaterials selective reduction.Direct flue gas stream represents "holy grail" in field, because typical concentration is only 6-15%, posing significant challenge electrolysis. On other hand, direct eliminates capture process simplifies overall utilization (CCU) scheme. However, frustrated by reactive oxygen (5-8%), low (6-15%), potentially toxic impurities. Surface O2 tolerance could be viable decarbonization gas.In addition electrocatalysts, incorporation into electrolyzer development suitable was also investigated meet demands. A membrane electrode assembly (MEA) zero-gap configuration cathode anode coated either side ion exchange membrane. We adopted MEA structural simplicity, ohmic resistance, efficiency. factors (for example, type, catalyst layer porosity, fabrication method) flow channels, diffusion layer) critical highly operation. separately anion-exchange membrane-based system CO production cation-exchange production. optimized can generate uniform current voltage distribution large-area operate stream. targets long-term continuous operation no electrolyte consumption.

Язык: Английский

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Catalyst Aggregation Matters for Immobilized Molecular CO₂RR Electrocatalysts

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(8), С. 4414 - 4420

Опубликована: Фев. 17, 2023

Here, we detail how the catalytic behavior of immobilized molecular electrocatalysts for CO2 reduction reaction (CO2RR) can be impacted by catalyst aggregation. Operando Raman spectroscopy was used to study CO2RR mediated a layer cobalt phthalocyanine (CoPc) on cathode an electrochemical flow reactor. We demonstrate that during electrolysis, oxidation state CoPc in is dependent upon degree Our data indicate catalysts must dispersed conductive supports mitigate formation aggregates and produce meaningful performance data. leveraged insights from this mechanistic engineer improved CO-forming catalyst─cobalt octaethoxyphthalocyanine (EtO8-CoPc)─that exhibited high selectivity (FECO ≥ 95%), partial current density (JCO 300 mA/cm2), durability (ΔFECO < 0.1%/h at 150 mA/cm2) cell. This work demonstrates accurately identify active species using operando use information implement into cells. also shows site catalysis cell metal center.

Язык: Английский

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Photocatalytic CO2 reduction with aminoanthraquinone organic dyes

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

Опубликована: Фев. 25, 2023

The direct utilization of solar energy to convert CO2 into renewable chemicals remains a challenge. One essential difficulty is the development efficient and inexpensive light-absorbers. Here we show series aminoanthraquinone organic dyes promote efficiency for visible light-driven reduction CO when coupled with an Fe porphyrin catalyst. Importantly, high turnover numbers can be obtained both photosensitizer catalyst, which has not been achieved in current systems. Structure-function study performed substituents having distinct electronic effects reveals that built-in donor-acceptor property significantly promotes photocatalytic activity. We anticipate this gives insight continued advanced photocatalysts conversion.

Язык: Английский

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Electrochemical CO₂ Reduction over Copper Phthalocyanine Derived Catalysts with Enhanced Selectivity for Multicarbon Products

ACS Catalysis, Год журнала: 2023, Номер 13(14), С. 9326 - 9335

Опубликована: Июнь 28, 2023

Metal complexes have shown impressive selectivity and activity as catalysts for electrochemical CO2 reduction (CO2RR), yet the nature of their active sites under operating conditions remains elusive. Herein, by using in situ Raman, X-ray photoelectron spectroscopy, advanced electron microscopy combination with density functional theory calculations, we reveal that copper phthalocyanine (CuPc) reconstructs during CO2RR, which proceeds through demetalation CuPc to Cu atoms followed agglomeration clusters finally nanoparticles (NPs). Further, find size NPs is highly dependent on several key experimental parameters, more importantly, multicarbon products positively correlated because large are rich grain boundaries. Specifically, at −0.73 V vs RHE 800 mA cm–2, CuPc-derived catalyst shows a maximum Faradaic efficiency 70%. These insights provide vital information future applications metal complex CO2RR expected inspire researchers design electrocatalysts other reactions.

Язык: Английский

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Iron-Complex-Based Supramolecular Framework Catalyst for Visible-Light-Driven CO₂Reduction

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(19), С. 10451 - 10457

Опубликована: Апрель 6, 2023

Molecule-based heterogeneous photocatalysts without noble metals are one of the most attractive systems for visible-light-driven CO2 reduction. However, reports on this class still limited, and their activities quite low compared to those containing metals. Herein, we report an iron-complex-based photocatalyst reduction with high activity. The key our success is use a supramolecular framework composed iron porphyrin complexes bearing pyrene moieties at meso positions. catalyst exhibited activity under visible-light irradiation (29100 μmol g-1 h-1 CO production, selectivity 99.9%), which highest among relevant systems. performance also excellent in terms apparent quantum yield production (0.298% 400 nm) stability (up 96 h). This study provides facile strategy create highly active, selective, stable utilizing

Язык: Английский

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