Combining theory and experiment in electrocatalysis: Insights into materials design

Science, Journal Year: 2017, Volume and Issue: 355(6321)

Published: Jan. 12, 2017

Better living through water-splitting Chemists have known how to use electricity split water into hydrogen and oxygen for more than 200 years. Nonetheless, because the electrochemical route is inefficient, most of made nowadays comes from natural gas. Seh et al. review recent progress in electrocatalyst development accelerate water-splitting, reverse reactions that underlie fuel cells, related oxygen, nitrogen, carbon dioxide reductions. A unified theoretical framework highlights need catalyst design strategies selectively stabilize distinct reaction intermediates relative each other. Science , this issue p. 10.1126/science.aad4998

Language: Английский

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Electrocatalysis for the oxygen evolution reaction: recent development and future perspectives

Chemical Society Reviews, Journal Year: 2017, Volume and Issue: 46(2), P. 337 - 365

Published: Jan. 1, 2017

We review the fundamental aspects of metal oxides, chalcogenides and pnictides as effective electrocatalysts for oxygen evolution reaction.

Language: Английский

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Noble metal-free hydrogen evolution catalysts for water splitting

Chemical Society Reviews, Journal Year: 2015, Volume and Issue: 44(15), P. 5148 - 5180

Published: Jan. 1, 2015

Sustainable hydrogen production is an essential prerequisite of a future economy. Water electrolysis driven by renewable resource-derived electricity and direct solar-to-hydrogen conversion based on photochemical photoelectrochemical water splitting are promising pathways for sustainable production. All these techniques require, among many things, highly active noble metal-free evolution catalysts to make the process more energy-efficient economical. In this review, we highlight recent research efforts toward synthesis electrocatalysts, especially at nanoscale, their catalytic properties reaction (HER). We review several important kinds heterogeneous non-precious metal including sulfides, selenides, carbides, nitrides, phosphides, heteroatom-doped nanocarbons. discussion, emphasis given synthetic methods HER strategies performance improvement, structure/composition-catalytic activity relationship. also summarize some examples showing that non-Pt electrocatalysts could serve as efficient cocatalysts promoting in both systems, when combined with suitable semiconductor photocatalysts.

Language: Английский

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Earth-abundant catalysts for electrochemical and photoelectrochemical water splitting

Nature Reviews Chemistry, Journal Year: 2017, Volume and Issue: 1(1)

Published: Jan. 11, 2017

Language: Английский

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Insight on Tafel slopes from a microkinetic analysis of aqueous electrocatalysis for energy conversion

Scientific Reports, Journal Year: 2015, Volume and Issue: 5(1)

Published: Sept. 8, 2015

Abstract Microkinetic analyses of aqueous electrochemistry involving gaseous H 2 or O , i.e., hydrogen evolution reaction (HER), oxidation (HOR), oxygen reduction (ORR) and (OER), are revisited. The Tafel slopes used to evaluate the rate determining steps generally assume extreme coverage adsorbed species (θ ≈ 0 ≈1), although, in practice, coverage-dependent. We conducted detailed kinetic describing coverage-dependent for aforementioned reactions. Our careful provide a general benchmark experimentally observed that can be assigned specific steps. analysis is powerful tool discussing involved electrocatalysis, but our study also demonstrated overly simplified assumptions led an inaccurate description surface electrocatalysis. Additionally, many studies, have been performed conjunction with Butler-Volmer equation, where its applicability regarding only electron transfer kinetics often overlooked. Based on derived HER/HOR as example, limitation expression electrocatalysis discussed this report.

Language: Английский

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What would it take for renewably powered electrosynthesis to displace petrochemical processes?

Science, Journal Year: 2019, Volume and Issue: 364(6438)

Published: April 25, 2019

BACKGROUND As the world continues to transition toward carbon emissions–free energy technologies, there remains a need also reduce emissions of chemical production industry. Today many world’s chemicals are produced from fossil fuel–derived feedstocks. Electrochemical conversion dioxide (CO 2 ) into feedstocks offers way turn waste valuable products, closing loop. When coupled renewable sources electricity, these products can be made with net negative footprint, helping sequester CO usable goods. Research and development electrocatalytic materials for reduction has intensified in recent years, advances selectivity, efficiency, reaction rate progressing practical implementation. A variety , such as alcohols, oxygenates, synthesis gas (syngas), olefins—staples global Because at substantial scale, switch renewably powered could result impact. The advancement electrochemical technology convert electrons generated power stable form represents one avenue long-term (e.g., seasonal) storage energy. ADVANCES science progress, priority given pinpoint more accurately targets application, economics barriers market entry. It will important scale electrolyzers increase stability catalysts thousands hours continuous operation. Product separation efficient recycling electrolyte managed. petrochemical industry operates massive complicated supply chain heavy capital costs. Commodity markets difficult penetrate priced on feedstock, which is currently inexpensive shale boom. capture costs flue or direct air product unreacted consider. Assuming that technologies apace, what it take disrupt sector, society gain by doing so? This review presents technoeconomic assessment ethylene, ethanol, monoxide, offering target figures merit application. price electricity far largest cost driver. begin match those traditional processes when prices fall below 4 cents per kWh efficiencies reach least 60%. footprint. comparative analysis electrocatalytic, biocatalytic, shows potential yield greatest emissions, provided steady clean available. Additionally, opportunities exist combine range other thermo- biocatalytic slowly electrify existing further upgrade useful chemicals. Technical challenges operating lifetime, discussed. Supply management entrenched industrial competition considered. OUTLOOK There exists increasingly widespread recognition means production. pricing mechanisms being developed seeing increased governmental support. nascent utilization economy gaining traction, startup companies, prizes, research efforts all pursuing new technologies. Recent through use diffusion electrodes pushing current densities selectivities realm use. Despite this remain technical must overcome commercial ultimately decide whether experiences conversion. Reduction using sourced transform commodity fuels.

Language: Английский

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Homogeneously dispersed multimetal oxygen-evolving catalysts

Science, Journal Year: 2016, Volume and Issue: 352(6283), P. 333 - 337

Published: March 25, 2016

Earth-abundant first-row (3d) transition metal-based catalysts have been developed for the oxygen-evolution reaction (OER); however, they operate at overpotentials substantially above thermodynamic requirements. Density functional theory suggested that non-3d high-valency metals such as tungsten can modulate 3d metal oxides, providing near-optimal adsorption energies OER intermediates. We a room-temperature synthesis to produce gelled oxyhydroxides materials with an atomically homogeneous distribution. These FeCoW exhibit lowest overpotential (191 millivolts) reported 10 milliamperes per square centimeter in alkaline electrolyte. The catalyst shows no evidence of degradation after more than 500 hours operation. X-ray absorption and computational studies reveal synergistic interplay between tungsten, iron, cobalt producing favorable local coordination environment electronic structure enhance energetics OER.

Language: Английский

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A highly active and stable IrO _x /SrIrO ₃ catalyst for the oxygen evolution reaction

Science, Journal Year: 2016, Volume and Issue: 353(6303), P. 1011 - 1014

Published: Sept. 1, 2016

Oxygen electrochemistry plays a key role in renewable energy technologies such as fuel cells and electrolyzers, but the slow kinetics of oxygen evolution reaction (OER) limit performance commercialization devices. Here we report an iridium oxide/strontium oxide (IrO x /SrIrO 3 ) catalyst formed during electrochemical testing by strontium leaching from surface layers thin films SrIrO . This has demonstrated specific activity at 10 milliamps per square centimeter (OER current normalized to area), with only 270 290 millivolts overpotential for 30 hours continuous acidic electrolyte. Density functional theory calculations suggest formation highly active IrO or anatase 2 motifs. The outperforms known ruthenium (RuO systems, other OER catalysts that have reasonable

Language: Английский

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Research opportunities to advance solar energy utilization

Science, Journal Year: 2016, Volume and Issue: 351(6271)

Published: Jan. 21, 2016

Major developments, as well remaining challenges and the associated research opportunities, are evaluated for three technologically distinct approaches to solar energy utilization: electricity, thermal, fuels technologies. Much progress has been made, but opportunities still present all approaches. Both evolutionary revolutionary technology development, involving foundational research, applied learning by doing, demonstration projects, deployment at scale will be needed continue this technology-innovation ecosystem. Most of offer potential provide much higher efficiencies, lower costs, improved scalability, new functionality, relative embodiments energy-conversion systems that have developed date.

Language: Английский

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Energy and fuels from electrochemical interfaces

Nature Materials, Journal Year: 2016, Volume and Issue: 16(1), P. 57 - 69

Published: Dec. 20, 2016

Language: Английский

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