Alcohols electrooxidation coupled with H2 production at high current densities promoted by a cooperative catalyst

AbstractElectrochemical alcohols oxidation offers a promising approach to produce valuable chemicals and facilitate coupled H2 production. However, the corresponding current density is very low at moderate cell potential that substantially limits the overall productivity. Here we report the electrooxidation of benzyl alcohol coupled with H2 production at high current density (540 mA cm−2 at 1.5 V vs. RHE) over a cooperative catalyst of Au nanoparticles supported on cobalt oxyhydroxide nanosheets (Au/CoOOH). The absolute current can further reach 4.8 A at 2.0 V in a more realistic two-electrode membrane-free flow electrolyzer. Experimental combined with theoretical results indicate that the benzyl alcohol can be enriched at Au/CoOOH interface and oxidized by the electrophilic oxygen species (OH*) generated on CoOOH, leading to higher activity than pure Au. Based on the finding that the catalyst can be reversibly oxidized/reduced at anodic potential/open circuit, we design an intermittent potential (IP) strategy for long-term alcohol electrooxidation that achieves high current density (>250 mA cm−2) over 24 h with promoted productivity and decreased energy consumption.

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Alcohols Enrichment Enables Their Electrooxidation Coupled with H2 Production at High Current Density

10.21203/rs.3.rs-119270/v1 ◽

2020 ◽

Author(s):

Zhenhua Li ◽

Yifan Yan ◽

Si-Min Xu ◽

Hua Zhou ◽

Ming Xu ◽

...

Keyword(s):

Benzyl Alcohol ◽

Current Density ◽

Au Nanoparticles ◽

High Current Density ◽

Local Environment ◽

H2 Production ◽

High Current ◽

Cell Potential ◽

Theoretical Results

Abstract Electrochemical alcohols oxidation offers a promising approach to produce industrial-relevant chemicals and facilitate coupled H 2 production. However, the corresponding current density is very low at moderate cell potential that substantially limits the overall productivity. Here, we report enrichment of alcohols in local environment over a cooperative catalyst of Au nanoparticles supported on cobalt oxyhydroxide nanosheets (Au/CoOOH), enabling alcohols electrooxidation at high current density. Specifically, the current density of benzyl alcohol electrooxidation can reach 523 mA cm− 2 at potential of 1.5 V vs. RHE. Experimental and theoretical results suggest that benzyl alcohol molecules are enriched on Au/CoOOH interface via strong d-π interaction. The enrichment has a broad substrate scope that involves alcohols with α-π bond including α-phenyl, C = C and C = O groups. Based on these findings, we design an intermittent potential (IP) strategy for long-term alcohol enrichment, achieving electrooxidation with current density of > 250 mA cm− 2 over 24 hours and promoted productivity.

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Long-term high resolution wear studies of high current density electrical brushes

Proceedings of the Fifty-First IEEE Holm Conference on Electrical Contacts, 2005. ◽

10.1109/holm.2005.1518261 ◽

2005 ◽

Cited By ~ 2

Author(s):

M.V.R. Skov Jensen

Keyword(s):

High Resolution ◽

Current Density ◽

High Current Density ◽

High Current

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Unexpected Genomic Features of High Current Density-Producing Geobacter sulfurreducens strain YM18

FEMS Microbiology Letters ◽

10.1093/femsle/fnab119 ◽

2021 ◽

Author(s):

Takashi Fujikawa ◽

Yoshitoshi Ogura ◽

Koki Ishigami ◽

Yoshihiro Kawano ◽

Miyuki Nagamine ◽

...

Keyword(s):

Electron Transfer ◽

Current Density ◽

Iron Reduction ◽

High Current Density ◽

Model Organism ◽

Geobacter Sulfurreducens ◽

Extracellular Electron Transfer ◽

High Current ◽

Current Production ◽

Current Densities

Abstract Geobacter sulfurreducens produces high current densities and it has been used as a model organism for extracellular electron transfer studies. Nine G. sulfurreducens strains were isolated from biofilms formed on an anode poised at –0.2 V (vs. SHE) in a bioelectrochemical system in which river sediment was used as an inoculum. The maximum current density of an isolate, strain YM18 (9.29 A/m2), was higher than that of the strains PCA (5.72 A/m2), the type strain of G. sulfurreducens, and comparable to strain KN400 (8.38 A/m2), which is another high current producing strain of G. sulfurreducens. Genomic comparison of strains PCA, KN400, and YM18 revealed that omcB, xapD, spc, and ompJ, which are known to be important genes for iron reduction and current production in PCA, were not present in YM18. In the PCA and KN400 genomes, two and one region (s) encoding CRISPR/Cas systems were identified, respectively, but they were missing in the YM18 genome. These results indicate that there is genetic variation in the key components involved in extracellular electron transfer among G. sulfurreducens strains.

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Selective Conversion of Carbon Dioxide to Formate with High Current Densities

Journal of Molecular and Engineering Materials ◽

10.1142/s2251237321500015 ◽

2021 ◽

pp. 2150001

Author(s):

Xiulin Yang ◽

Defei Liu ◽

Shenghong Zhong ◽

Xiaofeng Zhou ◽

Kuo-Wei Huang ◽

...

Keyword(s):

Current Density ◽

Hollow Fiber ◽

Active Sites ◽

Large Scale ◽

High Current Density ◽

High Current ◽

Faradaic Efficiency ◽

Practical Applications ◽

Selective Conversion ◽

Current Densities

Selective conversion of CO2 to formate with high current densities is highly desirable but still challenging. Copper hollow fibers with interconnected pore structures were fabricated via a facile method and used as a stand-alone cathode for highly efficient electrochemical reduction of CO2 to formate. Our studies revealed that delivering the reactant CO2 gas to the inner space of the hollow fiber could build up a higher CO2 partial pressure in the pores and presumably reduce the concentration of H[Formula: see text] from the electrolyte to effectively suppress the major competing reaction, hydrogen evolution reaction (HER), from 46.9% faradaic efficiency (FE) to 15.0%. A high selectivity for CO2 reduction to formate with a maximum FE of 77.1% was achieved with a high current density of 34.7[Formula: see text]mA cm[Formula: see text], which is one of the highest FEs on Cu-based materials. Mechanistic studies suggest that the abundant active sites along with the unique crystal facets induced by the high pressure of CO2 at the pore surface in the “gas in” mode are attributed to the superior electroactivity and selectivity for the CO2 reduction to formate. The Cu hollow fiber electrodes exhibit an outstanding long-term stability at high current density, showing great potential for large-scale practical applications.

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The spectrum of carbon arcs in air at high current densities

Proceedings of the Royal Society of London. Series A, Containing Papers of a Mathematical and Physical Character ◽

10.1098/rspa.1927.0172 ◽

1927 ◽

Vol 117 (776) ◽

pp. 164-182 ◽

Cited By ~ 9

Keyword(s):

Current Density ◽

High Current Density ◽

Short Note ◽

Direct Vision ◽

Ground Glass ◽

Total Radiation ◽

High Current ◽

Carbon Arc ◽

Current Densities ◽

Made In

Although the spectrum of the ordinary carbon arc has been studied in great detail during the last 70 years, there seems to have been no similar study of the “High Current Density” arc which was introduced by Beck in 1914. Spectrophotometrical measurements have been made in connection with the development of this type of arc for searchlights, and photographs of the spectra obtained from the total radiation from the arc have been published. The only account, however, of the spectrum from individual parts of the arc appears in a short note by Bell and Bassett. They examined an image of the arc on a ground glass screen with a direct vision spectroscope and reported that in the arc stream 15 lines appeared when the current exceeded 100 amperes. They attributed 7 of these to helium and 2 to hydrogen.

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Excellent performance of carbon-coated TiO2/Li4Ti5O12 composites with low Li/Ti ratio for Li-ion storage

RSC Advances ◽

10.1039/c5ra16930e ◽

2015 ◽

Vol 5 (113) ◽

pp. 93155-93161 ◽

Cited By ~ 10

Author(s):

Wei Yang ◽

Xue Bai ◽

Tao Li ◽

Yuan-Yuan Ma ◽

Yong-Xin Qi ◽

...

Keyword(s):

Current Density ◽

High Current Density ◽

Cycling Performance ◽

High Rate ◽

High Current ◽

Excellent Performance ◽

Ion Storage ◽

Carbon Coated ◽

Li Ion

Carbon-coated TiO2/Li4Ti5O12 composites with Li : Ti = 4 : 8 display high rate capacities and excellent long-term cycling performance at high current density.

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Layer-structured FeCo bihydroxide as an ultra-stable bifunctional electrocatalyst for water splitting at high current densities

Sustainable Energy & Fuels ◽

10.1039/d1se00380a ◽

2021 ◽

Author(s):

Chaoyang Sun ◽

Hui Wang ◽

Shan Ji ◽

Xuyun Wang ◽

Vladimir Linkov ◽

...

Keyword(s):

Water Splitting ◽

Current Density ◽

High Stability ◽

High Current Density ◽

High Current ◽

Bifunctional Electrocatalyst ◽

Current Densities ◽

Double Hydroxide

A layered FeCo double hydroxide bifunctional water cracking electrocatalyst with ultra-high stability at high current density was developed.

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Long-term electrically stable silver nanowire composite transparent electrode under high current density

Journal of Materials Science Materials in Electronics ◽

10.1007/s10854-021-06386-4 ◽

2021 ◽

Author(s):

Kaiqing Wang ◽

Yunxia Jin ◽

Fei Xiao

Keyword(s):

Current Density ◽

High Current Density ◽

Transparent Electrode ◽

Silver Nanowire ◽

High Current

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Long-Term Electrically Stable Silver Nanowire Composite Transparent Electrode Under High Current Density

10.21203/rs.3.rs-287036/v1 ◽

2021 ◽

Author(s):

Kaiqing Wang ◽

Yunxia Jin ◽

Fei Xiao

Keyword(s):

Current Density ◽

Composite Electrode ◽

High Current Density ◽

Transparent Electrode ◽

Silver Nanowire ◽

Electrical Performance ◽

High Current ◽

Electrical Stability ◽

Current Stress

Abstract Silver nanowire (AgNW) network has been employed to many electronic devices as transparent electrode. However, the poor electrical stability under current has been seriously holding its practical application, and we still lack long-term electrically stable AgNW system to study the underlying fundamental of electrical failure. In this work, the electrical performance and failure mechanism of chitosan-ascorbic acid (Chi-AsA)/AgNW composite under current stress were thoroughly studied. The composite electrode maintained stability above 24000 h under high current density of 100 mA cm-1. The main failure in AgNW composite is found to be a wave break perpendicular to the current rather than traditional uniform degradation across AgNW networks. More interestingly, the AgNWs in failed composite electrode kept their original smooth morphology excepting the crack area, while the AgNWs in pristine networks degraded to nanoparticles or became disconnected everywhere. The patterned AgNW composite in microscale exhibits similar long lifetime in resisting current stress as the bulk composite film. The effect of over-coating position, electrical stress, temperature and over-coating materials on the electrical stability were studied. The over-coating layer of Chi-AsA is proven to suppress the silver atoms from migration, reduce the concentrated Joule heating at junctions, and inhibit the corrosion. The Chi-AsA/AgNW composite enables electrically stable transparent conductor for next-generation optoelectronics, and the mechanism investigation may provide effective means of preparing electrically stable AgNW systems.

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