Production of Hydrogen Peroxide by Photocatalytic Processes

Angewandte Chemie International Edition, Год журнала: 2019, Номер 59(40), С. 17356 - 17376

Опубликована: Окт. 1, 2019

Hydrogen peroxide (H2 O2 ) has received increasing attention because it is not only a mild and environmentally friendly oxidant for organic synthesis environmental remediation but also promising new liquid fuel. The production of H2 by photocatalysis sustainable process, since uses water oxygen as the source materials solar light energy. Encouraging processes have been developed in last decade photocatalytic . In this Review we summarize research progress development After brief introduction emphasizing superiorities generation , basic principles establishing an efficient system generating are discussed, highlighting advanced photocatalysts used. This concluded summary outlook future advances emerging field.

Язык: Английский

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Atomic-level tuning of Co–N–C catalyst for high-performance electrochemical H2O2 production

Nature Materials, Год журнала: 2020, Номер 19(4), С. 436 - 442

Опубликована: Янв. 13, 2020

Язык: Английский

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Direct electrosynthesis of pure aqueous H ₂ O ₂ solutions up to 20% by weight using a solid electrolyte

Science, Год журнала: 2019, Номер 366(6462), С. 226 - 231

Опубликована: Окт. 11, 2019

Hydrogen peroxide (H2O2) synthesis generally requires substantial postreaction purification. Here, we report a direct electrosynthesis strategy that delivers separate hydrogen (H2) and oxygen (O2) streams to an anode cathode separated by porous solid electrolyte, wherein the electrochemically generated H+ HO2- recombine form pure aqueous H2O2 solutions. By optimizing functionalized carbon black catalyst for two-electron reduction, achieved >90% selectivity at current densities up 200 milliamperes per square centimeter, which represents productivity of 3.4 millimoles centimeter hour (3660 moles kilogram hour). A wide range concentrations solutions 20 weight % could be obtained tuning water flow rate through retained activity 100 hours.

Язык: Английский

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Atomically dispersed antimony on carbon nitride for the artificial photosynthesis of hydrogen peroxide

Nature Catalysis, Год журнала: 2021, Номер 4(5), С. 374 - 384

Опубликована: Май 21, 2021

Язык: Английский

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Tailoring Acidic Oxygen Reduction Selectivity on Single-Atom Catalysts via Modification of First and Second Coordination Spheres

Journal of the American Chemical Society, Год журнала: 2021, Номер 143(20), С. 7819 - 7827

Опубликована: Май 13, 2021

Product selectivity in multielectron electrocatalytic reactions is crucial to energy conversion efficiency and chemical production. However, a present practical drawback the limited understanding of actual catalytic active sites. Here, using as prototype single-atom catalysts (SACs) acidic oxygen reduction reaction (ORR), we report structure–property relationship show for first time that molecular-level local structure, including second coordination spheres (CSs), rather than individual atoms, synergistically determines response. ORR on Co-SACs can be tailored from four-electron two-electron pathway by modifying (N or/and O coordination) (C–O–C groups) CSs. Using combined theoretical predictions experiments, X-ray absorption fine structure analyses situ infrared spectroscopy, confirm unique change originates structure-dependent shift sites center Co atom O-adjacent C atom. We this optimizes electronic *OOH adsorption behavior give "best" activity >95% H2O2 electrosynthesis.

Язык: Английский

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Activity–Selectivity Trends in the Electrochemical Production of Hydrogen Peroxide over Single-Site Metal–Nitrogen–Carbon Catalysts

Journal of the American Chemical Society, Год журнала: 2019, Номер 141(31), С. 12372 - 12381

Опубликована: Июль 15, 2019

Nitrogen-doped carbon materials featuring atomically dispersed metal cations (M–N–C) are an emerging family of with potential applications for electrocatalysis. The electrocatalytic activity M–N–C toward four-electron oxygen reduction reaction (ORR) to H2O is a mainstream line research replacing platinum-group-metal-based catalysts at the cathode fuel cells. However, fundamental and practical aspects their two-electron ORR H2O2, future green "dream" process chemical industry, remain poorly understood. Here we combined computational experimental efforts uncover trends in electrochemical H2O2 production over series (M = Mn, Fe, Co, Ni, Cu) exclusively comprising M–Nx sites from molecular first-principles bench-scale electrolyzers operating industrial current density. We investigated effect nature 3d within on activity/selectivity (H2O2 products) (H2O2RR). Co–N–C catalyst was uncovered outstanding productivity considering its high activity, highest selectivity, lowest H2O2RR activity. activity–selectivity trend further analyzed by density functional theory, providing molecular-scale understandings volcano four- ORR. predicted binding energy HO* intermediate located near top accounting favorable demonstrated microflow cell, exhibiting unprecedented rate more than 4 mol peroxide gcatalyst–1 h–1 50 mA cm–2.

Язык: Английский

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Highly selective oxygen reduction to hydrogen peroxide on transition metal single atom coordination

Nature Communications, Год журнала: 2019, Номер 10(1)

Опубликована: Сен. 5, 2019

Shifting electrochemical oxygen reduction towards 2e- pathway to hydrogen peroxide (H2O2), instead of the traditional 4e- water, becomes increasingly important as a green method for H2O2 generation. Here, through flexible control pathways on different transition metal single atom coordination in carbon nanotube, we discovered Fe-C-O an efficient catalyst, with unprecedented onset 0.822 V versus reversible electrode 0.1 M KOH deliver mA cm-2 current, and high selectivity above 95% both alkaline neutral pH. A wide range tuning 2e-/4e- ORR was achieved via centers or neighboring metalloid coordination. Density functional theory calculations indicate that motifs, sharp contrast well-known Fe-C-N 4e-, are responsible pathway. This iron catalyst demonstrated effective water disinfection representative application.

Язык: Английский

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Selective Electrochemical H₂O₂ Production through Two‐Electron Oxygen Electrochemistry

Advanced Energy Materials, Год журнала: 2018, Номер 8(31)

Опубликована: Сен. 21, 2018

Abstract Direct electrochemical production of hydrogen peroxide (H 2 O ) through two‐electron oxygen electrochemistry, for example, the reduction in fuel cells or water oxidation electrolyzers, could provide an attractive alternative to locally produce this chemical on demand. The efficiency these processes depends greatly availability cost‐effective catalysts with high selectivity, activity, and stability. In recent years, various novel nanostructured materials have been reported selectively H . Through combined experimental theoretical approaches, underlying mechanisms synthesis via electrochemistry unveiled. Considering remarkable progress area, authors summarize developments regarding direct reactions. fundamental aspects reactions are first introduced. Various types that can effectively then presented. parallel, unique structure‐, component‐, composition‐dependent performance together catalytic discussed. Finally, a brief conclusion about achieved generation outlook future research challenges given.

Язык: Английский

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Unraveling the dual defect sites in graphite carbon nitride for ultra-high photocatalytic H₂O₂ evolution

Energy & Environmental Science, Год журнала: 2022, Номер 15(2), С. 830 - 842

Опубликована: Янв. 1, 2022

The g-C 3 N 4 with dual defect sites exhibits excellent photocatalytic H 2 O generation activity and selectivity, the key role of each site in surface reaction mechanism is revealed.

Язык: Английский

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Fenton/Fenton-like processes with in-situ production of hydrogen peroxide/hydroxyl radical for degradation of emerging contaminants: Advances and prospects

Journal of Hazardous Materials, Год журнала: 2020, Номер 404, С. 124191 - 124191

Опубликована: Окт. 7, 2020

Язык: Английский

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