Electrocatalytic Reduction of NO3– to Ultrapure Ammonia on {200} Facet Dominant Cu Nanodendrites with High Conversion Faradaic Efficiency

Developing sustainable energy strategies based on CO2 reduction is an increasingly important issue given the world’s continued reliance on hydrocarbon fuels and the rise in CO2 concentrations in the atmosphere. An important option is electrochemical or photoelectrochemical CO2 reduction to carbon fuels. We describe here an electrodeposition strategy for preparing highly dispersed, ultrafine metal nanoparticle catalysts on an electroactive polymeric film including nanoalloys of Cu and Pd. Compared with nanoCu catalysts, which are state-of-the-art catalysts for CO2 reduction to hydrocarbons, the bimetallic CuPd nanoalloy catalyst exhibits a greater than twofold enhancement in Faradaic efficiency for CO2 reduction to methane. The origin of the enhancement is suggested to arise from a synergistic reactivity interplay between Pd–H sites and Cu–CO sites during electrochemical CO2 reduction. The polymer substrate also appears to provide a basis for the local concentration of CO2 resulting in the enhancement of catalytic current densities by threefold. The procedure for preparation of the nanoalloy catalyst is straightforward and appears to be generally applicable to the preparation of catalytic electrodes for incorporation into electrolysis devices.

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Electrocatalytic reduction of CO2to CO with 100% faradaic efficiency by using pyrolyzed zeolitic imidazolate frameworks supported on carbon nanotube networks

Journal of Materials Chemistry A ◽

10.1039/c7ta08431e ◽

2017 ◽

Vol 5 (47) ◽

pp. 24867-24873 ◽

Cited By ~ 31

Author(s):

Ying Guo ◽

Huijuan Yang ◽

Xin Zhou ◽

Kunlong Liu ◽

Chao Zhang ◽

...

Keyword(s):

Carbon Nanotube ◽

Electrochemical Reduction ◽

Electrocatalytic Reduction ◽

Zeolitic Imidazolate Frameworks ◽

Faradaic Efficiency ◽

Carbon Nanotube Networks

100% faradaic efficiency is achieved in electrochemical reduction of CO2to COviacoupling between ZIFs and CNTs.

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Enhanced CO2 electroreduction efficiency through secondary coordination effects on a pincer iridium catalyst

Chemical Communications ◽

10.1039/c5cc00458f ◽

2015 ◽

Vol 51 (27) ◽

pp. 5947-5950 ◽

Cited By ~ 41

Author(s):

Steven T. Ahn ◽

Elizabeth A. Bielinski ◽

Elizabeth M. Lane ◽

Yanqiao Chen ◽

Wesley H. Bernskoetter ◽

...

Keyword(s):

Electrocatalytic Reduction ◽

Pincer Ligand ◽

Faradaic Efficiency ◽

Iridium Catalyst ◽

Co2 Electroreduction ◽

Low Overpotential

An iridium trihydride complex supported by a bifunctional pincer ligand promotes the electrocatalytic reduction of CO2 to formate in with excellent Faradaic efficiency and low overpotential.

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Hydrodechlorination of Dichloromethane by a Metal-Free Triazole-Porphyrin Electrocatalyst: Demonstration of Main-Group Element Electrocatalysis

10.26434/chemrxiv.12762266.v1 ◽

2020 ◽

Author(s):

Caroline Williams ◽

Amir Lashgari ◽

Marcus Ang ◽

Pranita Dhungana ◽

Jianbing Jiang

Keyword(s):

Current Density ◽

Catalytic Reaction ◽

Reaction Mechanisms ◽

Main Group ◽

Group Element ◽

Electrocatalytic Reduction ◽

Faradaic Efficiency ◽

Metal Free ◽

Main Group Element ◽

Proton Source

In this work, the electrocatalytic reduction of dichloromethane (CH2Cl2) into hydrocarbons involving a main group element-based molecular triazole-porphyrin electrocatalyst H2PorT8 is reported. This catalyst converted CH2Cl2 in acetonitrile to various hydrocarbons (methane, ethane, and ethylene) with a Faradaic efficiency of 70% and current density of –13 mA/cm2 at a potential of –2.2 V vs. Fc/Fc+ using water as a proton source. The findings of this study and its mechanistic interpretations demonstrated that H2PorT8 was an efficient and stable catalyst for the hydrodechlorination of CH2Cl2 and that main group catalysts could be potentially used for exploring new catalytic reaction mechanisms.

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Electrocatalytic hydrogenation of guaiacol in diverse electrolytes using a slurry reactor

10.1149/osf.io/36kg2 ◽

2019 ◽

Author(s):

Yanuar Philip Wijaya

Keyword(s):

Reduction Process ◽

Slurry Reactor ◽

Catalyst Loading ◽

Electrocatalytic Reduction ◽

Electrocatalytic Hydrogenation ◽

Perchloric Acid Solution ◽

Faradaic Efficiency ◽

Mild Conditions ◽

Constant Potential ◽

Low Catalyst Loading

Electrocatalytic hydrogenation-hydrogenolysis (ECH) of guaiacol was performed in an H-cell type of slurry reactor configuration with Pt/C catalyst. Different pairs of electrolytes, in catholyte-anolyte combinations, were investigated by constant potential chronocoulometry, showing that the acidic anolyte is preferable for an effective ECH. The advantages of this slurry reactor are mainly attributed to the enhanced Faradaic efficiency and recoverability of the catalyst. High guaiacol conversion (>90%) can be achieved at mild conditions (307 K, 1 atm) in perchloric acid solution (0.5 M), resulting in 54% cyclohexanol selectivity at moderate Faradaic efficiency (53%) and low catalyst loading. This work opens up the possibility of renewable synthesis of valuable chemicals from biomass-derived substrates via electrocatalytic reduction process at mild conditions.

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Exploring Electrocatalytic N2 under Varying Electrolyte Conditions

ECS Meeting Abstracts ◽

10.1149/ma2018-01/31/1895 ◽

2018 ◽

Vol MA2018-01 (31) ◽

pp. 1895-1895

Author(s):

Adam C. Nielander ◽

Joshua M McEnaney ◽

Thomas F Jaramillo

Keyword(s):

Molecular Nitrogen ◽

Supporting Electrolyte ◽

Electrocatalytic Reduction ◽

Efficient Synthesis ◽

High Nitrogen ◽

Faradaic Efficiency ◽

Nitrogen Reduction ◽

Reduction Activity ◽

Reduction And Oxidation ◽

Catalyst Selection

The activation of molecular nitrogen toward reduction is key to the efficient synthesis of valuable ammonia-based agricultural fertilizers. With this in mind, we have explored the electrocatalytic reduction and oxidation of N2 with a range of materials, including Re, Ni, and Fe metals predicted to have high nitrogen reduction activity via DFT calculations. The activity of these electrocatalytic materials toward nitrogen reduction and oxidation was evaluated under a range pressures (1-50 bar) and under a range of electrolyte conditions, including various pH levels, solvents (H2O, ethanol, THF), and supporting electrolyte salts (Li+, Na+, K+) to understand and minimize the loss of Faradaic efficiency for nitrogen due to concurrent hydrogen evolution. Our experimental results were compared to computationally predicted nitrogen reduction electrocatalytic activities in order to understand the mechanism of N2 activation as well as improve computational methods for further theory-based hypothesis generation and catalyst selection.

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Hydrodechlorination of Dichloromethane by a Metal-Free Triazole-Porphyrin Electrocatalyst: Demonstration of Main-Group Element Electrocatalysis

10.26434/chemrxiv.12762266 ◽

2020 ◽

Author(s):

Caroline Williams ◽

Amir Lashgari ◽

Marcus Ang ◽

Pranita Dhungana ◽

Jianbing Jiang

Keyword(s):

Current Density ◽

Catalytic Reaction ◽

Reaction Mechanisms ◽

Main Group ◽

Group Element ◽

Electrocatalytic Reduction ◽

Faradaic Efficiency ◽

Metal Free ◽

Main Group Element ◽

Proton Source

In this work, the electrocatalytic reduction of dichloromethane (CH2Cl2) into hydrocarbons involving a main group element-based molecular triazole-porphyrin electrocatalyst H2PorT8 is reported. This catalyst converted CH2Cl2 in acetonitrile to various hydrocarbons (methane, ethane, and ethylene) with a Faradaic efficiency of 70% and current density of –13 mA/cm2 at a potential of –2.2 V vs. Fc/Fc+ using water as a proton source. The findings of this study and its mechanistic interpretations demonstrated that H2PorT8 was an efficient and stable catalyst for the hydrodechlorination of CH2Cl2 and that main group catalysts could be potentially used for exploring new catalytic reaction mechanisms.

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