Co3O4 nanocrystals on graphene as a synergistic catalyst for oxygen reduction reaction

Nature Materials, Journal Year: 2011, Volume and Issue: 10(10), P. 780 - 786

Published: Aug. 5, 2011

Language: Английский

---

Solar Energy Supply and Storage for the Legacy and Nonlegacy Worlds

Chemical Reviews, Journal Year: 2010, Volume and Issue: 110(11), P. 6474 - 6502

Published: Nov. 10, 2010

ADVERTISEMENT RETURN TO ISSUEPREVReviewNEXTSolar Energy Supply and Storage for the Legacy Nonlegacy WorldsTimothy R. Cook, Dilek K. Dogutan, Steven Y. Reece, Yogesh Surendranath, Thomas S. Teets, Daniel G. Nocera*View Author Information Department of Chemistry, 6-335, Massachusetts Institute Technology, 77 Avenue, Cambridge, 02139-4307, United States* To whom correspondence should be addressed. E-mail: [email protected]Cite this: Chem. Rev. 2010, 110, 11, 6474–6502Publication Date (Web):November 10, 2010Publication History Received2 August 2010Published online10 November inissue 10 2010https://pubs.acs.org/doi/10.1021/cr100246chttps://doi.org/10.1021/cr100246creview-articleACS PublicationsCopyright © 2010 American Chemical SocietyRequest reuse permissionsArticle Views32426Altmetric-Citations2664LEARN ABOUT THESE METRICSArticle Views are COUNTER-compliant sum full text article downloads since 2008 (both PDF HTML) across all institutions individuals. These metrics regularly updated to reflect usage leading up last few days.Citations number other articles citing this article, calculated by Crossref daily. Find more information about citation counts.The Altmetric Attention Score is a quantitative measure attention that research has received online. Clicking on donut icon will load page at altmetric.com with additional details score social media presence given article. how calculated. Share Add toView InAdd Full Text ReferenceAdd Description ExportRISCitationCitation abstractCitation referencesMore Options onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose SUBJECTS:Batteries,Catalysts,Electrodes,Energy storage,Solar energy Get e-Alerts

Language: Английский

---

The Mechanism of Water Oxidation: From Electrolysis via Homogeneous to Biological Catalysis

ChemCatChem, Journal Year: 2010, Volume and Issue: 2(7), P. 724 - 761

Published: June 28, 2010

Abstract Striving for new solar fuels, the water oxidation reaction currently is considered to be a bottleneck, hampering progress in development of applicable technologies conversion light into storable fuels. This review compares and unifies viewpoints on from various fields catalysis research. The first part deals with thermodynamic efficiency mechanisms electrochemical splitting by metal oxides electrode surfaces, explaining recent concept potential‐determining step. Subsequently, novel cobalt oxide‐based catalysts heterogeneous (electro)catalysis are discussed. These may share structural functional properties surface oxides, multinuclear molecular catalytic manganese–calcium complex photosynthetic oxidation. Recent developments homogeneous water‐oxidation outlined focus discovery mononuclear ruthenium (and non‐ruthenium) complexes that efficiently mediate O 2 evolution water. Water photosynthesis subject concise presentation structure function natural paragon—the photosystem II—for which ideas concerning redox‐potential leveling, proton removal, OO bond formation last highlights common themes unifying concepts.

Language: Английский

---

The Artificial Leaf

Accounts of Chemical Research, Journal Year: 2012, Volume and Issue: 45(5), P. 767 - 776

Published: April 4, 2012

To convert the energy of sunlight into chemical energy, leaf splits water via photosynthetic process to produce molecular oxygen and hydrogen, which is in a form separated protons electrons. The primary steps natural photosynthesis involve absorption its conversion spatially electron–hole pairs. holes this wireless current are captured by evolving complex (OEC) photosystem II (PSII) oxidize oxygen. electrons produced as byproduct OEC reaction ferrodoxin I. With aid ferrodoxin–NADP+ reductase, they used hydrogen NADPH. For synthetic material realize solar function leaf, light-absorbing must capture photon generate that harnessed catalysts, drive four electron/hole fuel-forming water-splitting under benign conditions 1 sun (100 mW/cm2) illumination.This Account describes construction an artificial comprising earth-abundant elements interfacing triple junction, amorphous silicon photovoltaic with hydrogen- oxygen-evolving catalysts made from ternary alloy (NiMoZn) cobalt–phosphate cluster (Co-OEC), respectively. latter captures structural functional attributes PSII-OEC. Similar PSII-OEC, Co-OEC self-assembles upon oxidation metal ion 2+ 3+, may operate at room temperature, self-healing. also activates H2O proton-coupled electron transfer mechanism increased hole equivalents akin S-state pumping Kok cycle PSII. X-ray spectroscopy studies have established relative Mn3CaO4–Mn cubane where Co replaces Mn extended corner-sharing, head-to-tail dimer.The ability perform neutral or near-neutral has several consequences for leaf. NiMoZn be place Pt hydrogen. stabilize water, surface coated conducting oxide onto deposited. net result immersing triple-junction Si wafer holding it up can effect direct splitting. By constructing simple, stand-alone device composed materials, provides means inexpensive highly distributed solar-to-fuels system employs low-cost systems engineering manufacturing. Through type system, become viable supply those non-legacy world.

Language: Английский

---

Artificial Photosynthesis: Molecular Systems for Catalytic Water Oxidation

Chemical Reviews, Journal Year: 2014, Volume and Issue: 114(24), P. 11863 - 12001

Published: Oct. 29, 2014

ADVERTISEMENT RETURN TO ISSUEPREVReviewNEXTArtificial Photosynthesis: Molecular Systems for Catalytic Water OxidationMarkus D. Kärkäs*, Oscar Verho, Eric V. Johnston, and Björn Åkermark*View Author Information Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, SE-106 91 Stockholm, Sweden*E-mail: [email protected]*E-mail: protected]Cite this: Chem. Rev. 2014, 114, 24, 11863–12001Publication Date (Web):October 29, 2014Publication History Received11 October 2013Published online29 2014Published inissue 24 December 2014https://doi.org/10.1021/cr400572fCopyright © 2014 American Chemical SocietyRIGHTS & PERMISSIONSACS AuthorChoiceArticle Views36769Altmetric-Citations1068LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum full text article downloads since November 2008 (both PDF HTML) across all institutions individuals. These metrics regularly updated to reflect usage leading up last few days.Citations number other articles citing this article, calculated by Crossref daily. Find more information about citation counts.The Altmetric Attention Score is a quantitative measure attention that research has received online. Clicking on donut icon will load page at altmetric.com with additional details score social media presence given article. how calculated. Share Add toView InAdd Full Text ReferenceAdd Description ExportRISCitationCitation abstractCitation referencesMore Options onFacebookTwitterWechatLinked InReddit (39 MB) Get e-AlertsSUBJECTS:Catalysts,Ligands,Oxidation,Redox reactions,Transition metals e-Alerts

Language: Английский

---

Mechanistic Studies of the Oxygen Evolution Reaction by a Cobalt-Phosphate Catalyst at Neutral pH

Journal of the American Chemical Society, Journal Year: 2010, Volume and Issue: 132(46), P. 16501 - 16509

Published: Oct. 26, 2010

The mechanism of the oxygen evolution reaction (OER) by catalysts prepared electrodepositions from Co(2+) solutions in phosphate electrolytes (Co-Pi) was studied at neutral pH electrokinetic and (18)O isotope experiments. Low-potential enabled controlled preparation ultrathin Co-Pi catalyst films (<100 nm) that could be kinetically absence mass transport charge limitations to OER. exhibit a Tafel slope approximately equal 2.3 × RT/F for production water solutions. electrochemical rate law exhibits an inverse first order dependence on proton activity zeroth [Pi] ≥ 0.03 M. In buffer, is increased ∼3-fold overall greatly diminished. Together, these studies suggest involving rapid, one electron, equilibrium between Co(III)-OH Co(IV)-O which species acceptor, followed chemical turnover-limiting process oxygen-oxygen bond coupling.

Language: Английский

---

Toward practical solar hydrogen production – an artificial photosynthetic leaf-to-farm challenge

Chemical Society Reviews, Journal Year: 2019, Volume and Issue: 48(7), P. 1908 - 1971

Published: Jan. 1, 2019

Solar water splitting is a promising approach to transform sunlight into renewable, sustainable and green hydrogen energy. There are three representative ways of transforming solar radiation molecular hydrogen, which the photocatalytic (PC), photoelectrochemical (PEC), photovoltaic-electrolysis (PV-EC) routes. Having future perspective economy in mind, this review article discusses devices systems for solar-to-hydrogen production including comparison above systems. The focus placed on critical assessment key components needed scale up PEC such as materials efficiency, cost, elemental abundancy, stability, fuel separation, device operability, cell architecture, techno-economic aspects follows stepwise provides (i) summary basic principles employed splitting, (ii) an extensive discussion technologies, procedures, system designs, (iii) introduction international demonstration projects, development benchmarked large-scale prototype task scaling laboratory overall practical may be called "an artificial photosynthetic leaf-to-farm challenge".

Language: Английский

---

Oxygen Evolution Reaction Dynamics, Faradaic Charge Efficiency, and the Active Metal Redox States of Ni–Fe Oxide Water Splitting Electrocatalysts

Journal of the American Chemical Society, Journal Year: 2016, Volume and Issue: 138(17), P. 5603 - 5614

Published: March 31, 2016

Mixed Ni–Fe oxides are attractive anode catalysts for efficient water splitting in solar fuels reactors. Because of conflicting past reports, the catalytically active metal redox state catalyst has remained under debate. Here, we report an operando quantitative deconvolution charge injected into nanostructured oxyhydroxide OER or reaction product molecules. To achieve this, explore oxygen evolution dynamics and individual faradaic efficiencies using differential electrochemical mass spectrometry (DEMS). We further use X-ray absorption spectroscopy (XAS) conditions at Ni Fe K-edges electrocatalysts to evaluate oxidation states local atomic structure motifs. DEMS XAS data consistently reveal that up 75% centers increase their from +2 +3, while 25% arrive +4 NiOOH catalysis. The remain +3 state, regardless potential composition. For mixed Ni100–xFex catalysts, where x exceeds 9 %, efficiency O2 sharply increases ∼30% 90%, suggesting atoms largely catalytic conditions. reconcile apparent low level oxidized hypothesize a kinetic competition between (i) process (ii) reduction step during release may account insignificant accumulation detectable high-valent if rate outweighs (i). conclude discussion superior activity Ni–FeOOH terms surface catalysis redox-inactive sites likely represents oversimplification fails capture essential aspects synergisms highly sites.

Language: Английский

---

Nickel-borate oxygen-evolving catalyst that functions under benign conditions

Proceedings of the National Academy of Sciences, Journal Year: 2010, Volume and Issue: 107(23), P. 10337 - 10341

Published: May 8, 2010

Thin catalyst films with electrocatalytic water oxidation properties similar to those of a recently reported Co-based can be electrodeposited from dilute Ni(2+) solutions in borate electrolyte at pH 9.2 (B(i)). The Ni-B(i) prepared precise thickness control and operate modest overpotential providing an alternative the Co for applications solar energy conversion.

Language: Английский

---

Structure and Valency of a Cobalt−Phosphate Water Oxidation Catalyst Determined by in Situ X-ray Spectroscopy

Journal of the American Chemical Society, Journal Year: 2010, Volume and Issue: 132(39), P. 13692 - 13701

Published: Sept. 14, 2010

A water oxidation catalyst generated via electrodeposition from aqueous solutions containing phosphate and Co2+ (Co−Pi) has been studied by in situ X-ray absorption spectroscopy. Spectra were obtained for Co−Pi films of two different thicknesses at an applied potential supporting catalysis open circuit. Extended fine structure (EXAFS) spectra indicate the presence bis-oxo/hydroxo-bridged Co subunits incorporated into higher nuclearity clusters Co−Pi. The average cluster is greater a relatively thick film (∼40−50 nmol ions/cm2) deposited 1.25 V vs NHE than extremely thin (∼3 1.1 V. near edge (XANES) electrochemical data support valency 3 both samples when catalyzing Upon switching to circuit, undergoes continuous reduction due residual catalysis, as indicated negative shift energy. rate depends on size. On basis structural parameters extracted fits EXAFS with comparisons oxide compounds, model proposed wherein oxo/hydroxo are composed edge-sharing CoO6 octahedra, motif found cobaltates. Whereas cobaltates contain extended planes molecular dimensions.

Language: Английский

---