Beyond fossil fuel–driven nitrogen transformations

Science, Год журнала: 2018, Номер 360(6391)

Опубликована: Май 24, 2018

Nitrogen is fundamental to all of life and many industrial processes. The interchange nitrogen oxidation states in the production ammonia, nitric acid, other commodity chemicals largely powered by fossil fuels. A key goal contemporary research field chemistry minimize use fuels developing more efficient heterogeneous, homogeneous, photo-, electrocatalytic processes or adapting enzymatic underlying natural cycle. These approaches, as well challenges involved, are discussed this Review.

Язык: Английский

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Unveiling the Activity Origin of a Copper‐based Electrocatalyst for Selective Nitrate Reduction to Ammonia

Angewandte Chemie International Edition, Год журнала: 2020, Номер 59(13), С. 5350 - 5354

Опубликована: Янв. 22, 2020

Abstract Unveiling the active phase of catalytic materials under reaction conditions is important for construction efficient electrocatalysts selective nitrate reduction to ammonia. The origin prominent activity enhancement CuO (Faradaic efficiency: 95.8 %, Selectivity: 81.2 %) toward electroreduction ammonia was probed. 15 N isotope labeling experiments showed that originated from reduction. 1 H NMR spectroscopy and colorimetric methods were performed quantify In situ Raman ex revealed electrochemically converted into Cu/Cu 2 O, which serves as an phase. combined results online differential electrochemical mass spectrometry (DEMS) DFT calculations demonstrated electron transfer Cu O at interface could facilitate formation *NOH intermediate suppress hydrogen evolution reaction, leading high selectivity Faradaic efficiency.

Язык: Английский

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A Review of Electrocatalytic Reduction of Dinitrogen to Ammonia under Ambient Conditions

Advanced Energy Materials, Год журнала: 2018, Номер 8(22)

Опубликована: Май 21, 2018

Abstract The production of ammonia (NH 3 ) from molecular dinitrogen (N 2 under mild conditions is one the most attractive topics in field chemistry. Electrochemical reduction N promising for achieving clean and sustainable NH with lower energy consumption using renewable sources. To date, emerging electrocatalysts electrochemical to at room temperature atmospheric pressure remain largely underexplored. major challenge achieve both high catalytic activity selectivity. Here, recent progress on nitrogen reaction (NRR) ambient theoretical experimental aspects summarized, aiming extracting instructive perceptions future NRR research activities. prevailing theories mechanisms as well computational screening materials are presented. State‐of‐the‐art heterogeneous rational design whole systems involved. Importantly, strategies enhance activity, selectivity, efficiency, stability toward proposed. Moreover, determination methods compared problems relating possible contamination system mentioned so shed fresh light standard protocols measurements.

Язык: Английский

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Electrochemical ammonia synthesis via nitrate reduction on Fe single atom catalyst

Nature Communications, Год журнала: 2021, Номер 12(1)

Опубликована: Май 17, 2021

Abstract Electrochemically converting nitrate, a widespread water pollutant, back to valuable ammonia is green and delocalized route for synthesis, can be an appealing supplementary alternative the Haber-Bosch process. However, as there are other nitrate reduction pathways present, selectively guiding reaction pathway towards currently challenged by lack of efficient catalysts. Here we report selective active on Fe single atom catalyst, with maximal Faradaic efficiency ~ 75% yield rate up 20,000 μg h −1 mg cat. (0.46 mmol cm −2 ). Our catalyst effectively prevent N-N coupling step required N 2 due neighboring metal sites, promoting product selectivity. Density functional theory calculations reveal mechanisms potential limiting steps atomically dispersed sites.

Язык: Английский

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Recent Advances and Challenges of Electrocatalytic N₂Reduction to Ammonia

Chemical Reviews, Год журнала: 2020, Номер 120(12), С. 5437 - 5516

Опубликована: Май 27, 2020

Global ammonia production reached 175 million metric tons in 2016, 90% of which is produced from high purity N2 and H2 gases at temperatures pressures via the Haber–Bosch process. Reliance on natural gas for results large energy consumption CO2 emissions. Concerns human-induced climate change are spurring an international scientific effort to explore new approaches reduce its carbon footprint. Electrocatalytic reduction attractive alternative that can potentially enable synthesis under milder conditions small-scale, distributed, on-site electrolysis cells powered by renewable electricity generated solar or wind sources. This review provides a comprehensive account theoretical experimental studies electrochemical nitrogen fixation with focus low selectivity versus protons H2. A detailed introduction detection methods execution control experiments given as they crucial accurate reporting findings. The main part this focuses progress has been achieved range conditions. Finally, comments current challenges potential opportunities field provided.

Язык: Английский

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Boron-Doped Graphene for Electrocatalytic N2 Reduction

Joule, Год журнала: 2018, Номер 2(8), С. 1610 - 1622

Опубликована: Июнь 26, 2018

Язык: Английский

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Tuning Oxygen Vacancies in Ultrathin TiO₂ Nanosheets to Boost Photocatalytic Nitrogen Fixation up to 700 nm

Advanced Materials, Год журнала: 2019, Номер 31(16)

Опубликована: Март 4, 2019

Dinitrogen reduction to ammonia using transition metal catalysts is central both the chemical industry and Earth's nitrogen cycle. In Haber-Bosch process, a metallic iron catalyst high temperatures (400 °C) pressures (200 atm) are necessary activate cleave NN bonds, motivating search for alternative that can transform N2 NH3 under far milder reaction conditions. Here, successful hydrothermal synthesis of ultrathin TiO2 nanosheets with an abundance oxygen vacancies intrinsic compressive strain, achieved through facile copper-doping strategy, reported. These defect-rich anatase exhibit remarkable stable performance photocatalytic in water, exhibiting photoactivity up 700 nm. The strain effect allow strong chemisorption activation molecular resulting unusually rates evolution visible-light irradiation. Therefore, this study offers promising sustainable route fixation atmospheric solar energy.

Язык: Английский

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Metal-Free Single Atom Catalyst for N₂ Fixation Driven by Visible Light

Journal of the American Chemical Society, Год журнала: 2018, Номер 140(43), С. 14161 - 14168

Опубликована: Окт. 4, 2018

Solar nitrogen (N2) fixation is the most attractive way for sustainable production of ammonia (NH3), but development a highly active, long-term stable and low-cost catalyst remains great challenge. Current research efforts N2 reduction mainly focus on metal-based catalysts using electrochemical approach, while metal-free or solar-driven have been rarely explored. Herein, basis concept electron "acceptance-donation", photocatalyst, namely, boron (B) atom, decorated optically active graphitic-carbon nitride (B/g-C3N4), proposed by extensive first-principles calculations. Our results reveal that gas phase can be efficiently reduced into NH3 B/g-C3N4 through enzymatic mechanism with record low onset potential (0.20 V). Moreover, B-decorated g-C3N4 significantly enhance visible light absorption, rendering them ideal N2. Importantly, as-designed further demonstrated to hold promise synthesis due its extremely high stability. work first report single atom photocatalyst reduction, offering cost-effective opportunities advancing production.

Язык: Английский

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Achieving a Record‐High Yield Rate of 120.9 for N₂ Electrochemical Reduction over Ru Single‐Atom Catalysts

Advanced Materials, Год журнала: 2018, Номер 30(40)

Опубликована: Авг. 10, 2018

The electrochemical reduction of N

Язык: Английский

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How to explore ambient electrocatalytic nitrogen reduction reliably and insightfully

Chemical Society Reviews, Год журнала: 2019, Номер 48(12), С. 3166 - 3180

Опубликована: Янв. 1, 2019

The efficient activation of dinitrogen for the production ammonia plays a crucial role in our modern society, considering significant impact on food, chemicals, and energy. As an attractive alternative to century-old Haber-Bosch process which is responsible 1-2% global energy consumption, utilization half hydrogen produced globally, ∼1% energy-related CO2 emissions, ambient electrocatalytic nitrogen reduction reaction has attracted tremendous interest during past few years. Some achievements have revealed possibility this process, but also identified great challenges. activity selectivity are fundamentally limited by competing evolution scaling relations, while low rates ubiquitous contaminants plague experimental practices. Aiming toward higher accuracy reproducibility claimed results, more meaningful, impactful, insightful research, tutorial review summarizes present status challenges study reduction, followed thorough discussion various parameters. We then recommend series protocols best practices experiments, highlight some potential directions future research exciting important field.

Язык: Английский

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