A molecular (NCS2)Ni(II) electrocatalyst resembles [NiFe]hydrogenase pathway for H2 evolution

The electrochemical hydrogen evolution reaction (HER) is considered a sustainable energy approach to advance fuel-cell technologies, and HER electrocatalysts that resembles the [NiFe] hydrogenases are highly desired. Herein, we report a bioinspired Ni(II) complex (NCHS2)Ni(OTf)2, where NCHS2 is 3,7-dithia-1(2,6)-pyridina-5(1,3)-benzenacyclooctaphane, that is an efficient electrocatalyst for HER with turnover frequencies up to 400,000 s–1 in the presence of low acid concentration, and compares favorably with the other reported Ni HER electrocatalysts. Importantly, in this complex the rationally designed NCHS2 ligand undergoes C-H bond activation and the resulting organometallic Ni-aryl complex restricts the formation of a Ni(0) species, which resembles the role of the cysteine ligands in [NiFe] hydrogenases. In addition, this electrocatalyst follows a unique HER mechanism via detectable Ni(I)/Ni(III) intermediates that are also proposed for [NiFe] hydrogenases, yet such a mechanism has not been observed to date in model systems.

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Unveiling the Role of 2D Monolayer Mn-doped MoS2 Material: Toward an Efficient Electrocatalyst for H2 Evolution Reaction

Physical Chemistry Chemical Physics ◽

10.1039/d1cp04344g ◽

2021 ◽

Author(s):

Joy Ekka ◽

Shrish Nath Upadhyay ◽

Jena Akash Kumar Satrughna ◽

Frerich Keil ◽

Srimanta Pakhira

Keyword(s):

Transition Metal ◽

Hydrogen Evolution ◽

Hydrogen Evolution Reaction ◽

Transition Metal Dichalcogenides ◽

Two Dimensional ◽

H2 Evolution ◽

Metal Dichalcogenides ◽

Mn Doped

Two-dimensional (2D) monolayer pristine MoS2 transition metal dichalcogenides (TMD) is the most studied material because of its promising aspects as nonprecious electrocatalyst for hydrogen evolution reaction (HER). Previous studies have...

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The Role of Cations and Electrolyte pH in the Hydrogen Evolution Reaction on Au in Alkaline Media

10.29363/nanoge.ecocat.2020.006 ◽

2020 ◽

Author(s):

Akansha Goyal ◽

Marc T.M. Koper

Keyword(s):

Hydrogen Evolution ◽

Hydrogen Evolution Reaction ◽

Alkaline Media ◽

Electrolyte Ph

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Flower-like tungsten-doped Fe–Co phosphides as efficient electrocatalysts for hydrogen evolution reaction

CrystEngComm ◽

10.1039/d1ce00426c ◽

2021 ◽

Author(s):

Qian Zhang ◽

Shuihua Tang ◽

Lieha Shen ◽

Weixiang Yang ◽

Zhen Tang ◽

...

Keyword(s):

Fuel Cell ◽

Hydrogen Evolution ◽

Hydrogen Evolution Reaction ◽

Adsorption Energy ◽

High Performance ◽

Hydrogen Adsorption ◽

Cost Effective

Developing cost-effective and high-performance electrocatalysts for hydrogen evolution reaction (HER) are imperative thanks to rapid increase of fuel-cell driven vehicles. Tungsten (W) possesses advantages of optimized hydrogen adsorption energy and...

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A Mini Review on Doped Nickel-Based Electrocatalysts for Hydrogen Evolution Reaction

Energies ◽

10.3390/en13184651 ◽

2020 ◽

Vol 13 (18) ◽

pp. 4651

Author(s):

Yilin Deng ◽

Wei Lai ◽

Bin Xu

Keyword(s):

Hydrogen Evolution ◽

Hydrogen Evolution Reaction ◽

Water Electrolysis ◽

Energy Resources ◽

Alkaline Media ◽

Hydrogen Energy ◽

Heteroatom Doping ◽

Highly Active ◽

Production Of Hydrogen

The energy crisis and environmental pollution have attracted much attention and have promoted researches on clean and sustainable hydrogen energy resources. With the help of highly active and stable transition metal nickel-based catalysts, the production of hydrogen from water electrolysis from electrolyzed water has become an inexpensive and efficient strategy for generating hydrogen energy. In recent years, heteroatom doping has been found to be an effective strategy to improve the electrocatalytic hydrogen evolution reaction (HER) performances of nickel-based catalysts in acidic, neutral, and alkaline media. This review will highlight many recent works of inexpensive and readily available heteroatom-doped nickel-based HER catalysts. The evaluation methods for the performances of HER catalyst will be briefly described, and the role of heteroatom doping and its application in nickel-based catalyst will be summarized. This article will also point out some heteroatom doping strategies, which may provide references and inspire the design of other catalysts with dopants.

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Role of Hyper-Reduced States in Hydrogen Evolution Reaction at Sulfur Vacancy in MoS2

ACS Catalysis ◽

10.1021/acscatal.8b00883 ◽

2018 ◽

Vol 8 (5) ◽

pp. 4508-4515 ◽

Cited By ~ 17

Author(s):

Kye Yeop Kim ◽

Joohee Lee ◽

Sungwoo Kang ◽

Young-Woo Son ◽

Ho Won Jang ◽

...

Keyword(s):

Hydrogen Evolution ◽

Hydrogen Evolution Reaction ◽

Sulfur Vacancy

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Role of the Edge Properties in the Hydrogen Evolution Reaction on MoS2

Chemistry - A European Journal ◽

10.1002/chem.201605848 ◽

2017 ◽

Vol 23 (20) ◽

pp. 4863-4869 ◽

Cited By ~ 21

Author(s):

Petr Lazar ◽

Michal Otyepka

Keyword(s):

Hydrogen Evolution ◽

Hydrogen Evolution Reaction

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Atoms vs. Ions: Intermediates in Reversible Electrochemical Hydrogen Evolution Reaction

Catalysts ◽

10.3390/catal11091135 ◽

2021 ◽

Vol 11 (9) ◽

pp. 1135

Author(s):

Jurga Juodkazytė ◽

Kȩstutis Juodkazis ◽

Saulius Juodkazis

Keyword(s):

Electron Transfer ◽

Hydrogen Evolution ◽

Hydrogen Evolution Reaction ◽

Ionic Species ◽

Absolute Temperature ◽

Main Reaction ◽

Adsorbed Hydrogen ◽

H2 Evolution ◽

Hydrogen Electrode ◽

Reported Data

We present a critical analysis of the mechanism of reversible hydrogen evolution reaction based on thermodynamics of hydrogen processes considering atomic and ionic species as intermediates. Clear distinction between molecular hydrogen evolution/oxidation (H2ER and H2OR) and atomic hydrogen evolution/oxidation (HER and HOR) reactions is made. It is suggested that the main reaction describing reversible H2ER and H2OR in acidic and basic solutions is: H3O++2e−⇌(H2+)adH2+OH− and its standard potential is E0 = −0.413 V (vs. standard hydrogen electrode, SHE). We analyse experimentally reported data with models which provide a quantitative match (R.J.Kriek et al., Electrochem. Sci. Adv. e2100041 (2021)). Presented analysis implies that reversible H2 evolution is a two-electron transfer process which proceeds via the stage of adsorbed hydrogen molecular ion H2+ as intermediate, rather than Had as postulated in the Volmer-Heyrovsky-Tafel mechanism. We demonstrate that in theory, two slopes of potential vs. lg(current) plots are feasible in the discussed reversible region of H2 evolution: 2.3RT/F≈60 mV and 2.3RT/2F≈30 mV, which is corroborated by the results of electrocatalytic hydrogen evolution studies reported in the literature. Upon transition to irreversible H2ER, slowdown of H2+ formation in the first electron transfer stage manifests, and the slope increases to 2.3RT/0.5F≈120 mV; R,F,T are the universal gas, Faraday constants and absolute temperature, respectively.

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Boosting alkaline hydrogen evolution: the dominating role of interior modification in surface electrocatalysis

Energy & Environmental Science ◽

10.1039/d0ee01750g ◽

2020 ◽

Vol 13 (9) ◽

pp. 3110-3118 ◽

Cited By ~ 6

Author(s):

Zhao Li ◽

Wenhan Niu ◽

Zhenzhong Yang ◽

Abdelkader Kara ◽

Qi Wang ◽

...

Keyword(s):

Hydrogen Evolution ◽

Hydrogen Evolution Reaction ◽

Water Dissociation ◽

Alkaline Solutions ◽

Great Promise ◽

Hydrogen Fuel ◽

Practical Utilization

The alkaline hydrogen evolution reaction (A-HER) holds great promise for clean hydrogen fuel generation but its practical utilization is severely hindered by the sluggish kinetics for water dissociation in alkaline solutions.

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