W2C-Supported PtAuSn—A Catalyst with the Earliest Ethanol Oxidation Onset Potential and the Highest Ethanol Conversion Efficiency to CO2 Known till Date

AbstractDirect ethanol fuel cells (DEFC) still lack active and efficient electrocatalysts for the alkaline ethanol oxidation reaction (EOR). In this work, a new instant reduction synthesis method was developed to prepare carbon supported ternary PdNiBi nanocatalysts with improved EOR activity. Synthesized catalysts were characterized with a variety of structural and compositional analysis techniques in order to correlate their morphology and surface chemistry with electrochemical performance. The modified instant reduction synthesis results in well-dispersed, spherical Pd85Ni10Bi5 nanoparticles on Vulcan XC72R support (Pd85Ni10Bi5/C(II-III)), with sizes ranging from 3.7 ± 0.8 to 4.7 ± 0.7 nm. On the other hand, the common instant reduction synthesis method leads to significantly agglomerated nanoparticles (Pd85Ni10Bi5/C(I)). EOR activity and stability of these three different carbon supported PdNiBi anode catalysts with a nominal atomic ratio of 85:10:5 were probed via cyclic voltammetry and chronoamperometry using the rotating disk electrode method. Pd85Ni10Bi5/C(II) showed the highest electrocatalytic activity (150 mA⋅cm−2; 2678 mA⋅mg−1) with low onset potential (0.207 V) for EOR in alkaline medium, as compared to a commercial Pd/C and to the other synthesized ternary nanocatalysts Pd85Ni10Bi5/C(I) and Pd85Ni10Bi5/C(III). This new synthesis approach provides a new avenue to developing efficient, carbon supported ternary nanocatalysts for future energy conversion devices.

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Impacts of Kafirin Allelic Diversity, Starch Content, and Protein Digestibility on Ethanol Conversion Efficiency in Grain Sorghum

Cereal Chemistry ◽

10.1094/cchem-04-13-0068-r ◽

2014 ◽

Vol 91 (3) ◽

pp. 218-227 ◽

Cited By ~ 13

Author(s):

Julia E. Cremer ◽

Liman Liu ◽

Scott R. Bean ◽

Jae-Bom Ohm ◽

Michael Tilley ◽

...

Keyword(s):

Conversion Efficiency ◽

Starch Content ◽

Allelic Diversity ◽

Protein Digestibility ◽

Grain Sorghum ◽

Ethanol Conversion

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Impact of the modification of carbon-supported, Pt-based catalysts by irreversibly adsorbed Sn, Ru and Rh on ethanol oxidation

Journal of the Serbian Chemical Society ◽

10.2298/jsc110217136l ◽

2011 ◽

Vol 76 (11) ◽

pp. 1523-1536 ◽

Cited By ~ 1

Author(s):

Jelena Lovic ◽

Amalija Tripkovic ◽

Ksenija Popovic

Keyword(s):

Surface Coverage ◽

Ethanol Oxidation ◽

Bond Breaking ◽

Irreversible Adsorption ◽

Potential Region ◽

Onset Potential ◽

Bifunctional Mechanism ◽

Modified Surfaces ◽

Current Densities ◽

Oxidation Of Ethanol

The oxidation of ethanol was studied at Snad-, Ruad- and Rhadmodified and unmodified PtC, Pt3Sn/C and Pt3Ru2/C catalysts. Potentiodynamic, quasi-steady-state and chronoamperometric measurements were used to investigate the activity and stability of the catalysts. Irreversible adsorption of a small amount of each of the adatoms (?10 % surface coverage) enhanced the activity of the Pt/C and Pt3Sn/C catalysts. The onset potential was shifted by ?50 mV towards lower values and the current densities over the whole studied potential region were up to two times higher with respect to the unmodified catalysts. On the other hand, the addition of Snad or Rhad slightly increased the activity of Pt3Ru2/C, while the presence of Ruad decreased its activity for ethanol oxidation. The catalytic action of Snad and Ruad was associated mostly with their ability to adsorb oxygen-containing species at lower potentials than Pt, permitting a bifunctional mechanism to proceed. Rhad also acted on the C-C bond breaking activation as well as source of oxygen containing species, increasing in this way the activity of the modified surfaces for ethanol oxidation.

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Defect-rich decorated TiO2 nanowires for super-efficient photoelectrochemical water splitting driven by visible light

Energy & Environmental Science ◽

10.1039/c5ee01615k ◽

2015 ◽

Vol 8 (11) ◽

pp. 3363-3373 ◽

Cited By ~ 61

Author(s):

Md Anisur Rahman ◽

Samad Bazargan ◽

Saurabh Srivastava ◽

Xiongyao Wang ◽

Marwa Abd-Ellah ◽

...

Keyword(s):

Visible Light ◽

Water Splitting ◽

Conversion Efficiency ◽

Photoelectrochemical Water Splitting ◽

Visible Light Region ◽

Tio2 Nanowires ◽

High Conversion Efficiency ◽

Splitting Property ◽

Onset Potential ◽

Light Region

Defect-rich 1D TiO2 nanostructures show excellent photoelectrochemical water splitting property in the visible light region with a low onset potential of 0.3 V vs. RHE and a remarkably high conversion efficiency of 3.6%.

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Microwave sinthesys and characterization of Pt and Pt-Rh-Sn electrocatalysts for ethanol oxidation

Journal of the Serbian Chemical Society ◽

10.2298/jsc110405166s ◽

2011 ◽

Vol 76 (12) ◽

pp. 1673-1685

Author(s):

Sanja Stevanovic ◽

Dusan Tripkovic ◽

Dejan Poleti ◽

Jelena Rogan ◽

Amalija Tripkovic ◽

...

Keyword(s):

Ethylene Glycol ◽

Ethanol Oxidation ◽

Carbon Support ◽

Xrd Analysis ◽

Face Centered Cubic ◽

Onset Potential ◽

Bifunctional Mechanism ◽

Highly Active ◽

The Stability ◽

Glycol Solution

Carbon supported Pt and Pt-Rh-Sn catalysts were synthesized by microwave-polyol method in ethylene glycol solution and investigated for the ethanol electro-oxidation reaction. The catalysts were characterized in terms of structure, morphology and composition by employing XRD, STM and EDX techniques. STM analysis indicated rather uniform particles and particle size of below 2 nm for both catalysts. XRD analysis of the Pt/C catalyst revealed two phases, one with the main characteristic peaks of face centered cubic crystal structure (fcc) of platinum and another related to graphite like structure of carbon support Vulcan XC-72R. However, in XRD pattern of the Pt-Rh-Sn/C catalyst diffraction peaks for Pt, Rh or Sn cannot be resolved, indicating an extremely low crystallinity. The small particle sizes and homogeneous size distributions of both catalysts should be attributed to the advantages of microwave assisted modified polyol process in ethylene glycol solution. Pt-Rh- Sn/C catalyst is highly active for the ethanol oxidation with the onset potential shifted for more than 150 mV to negative values and with currents nearly 5 times higher in comparison to Pt/C catalyst. The stability tests of the catalysts, as studied by the chronoamperometric experiments, reveal that the Pt-Rh-Sn/C catalyst is evidently less poisoned then Pt/C catalyst. The increased activity of Pt-Rh-Sn/C in comparison to Pt/C catalyst is most probably promoted by bifunctional mechanism and the electronic effect of alloyed metals.

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Preparation and Characterization of the PdW/MWCNT Anode Catalyst for Alkaline Direct Ethanol Fuel Cells

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.448-453.2986 ◽

2013 ◽

Vol 448-453 ◽

pp. 2986-2989 ◽

Cited By ~ 1

Author(s):

Wei Min Chen ◽

Yu Zhang

Keyword(s):

Ethanol Oxidation ◽

Reduction Method ◽

Alkaline Media ◽

Support Surface ◽

Ethanol Electrooxidation ◽

Anode Catalyst ◽

Direct Ethanol Fuel Cells ◽

Onset Potential ◽

Catalytic Performances

The tungsten modified Pd-based nanocatalyst for ethanol oxidation in alkaline media was prepared by an ethylene glycol reduction method, and the catalytic performances of the prepared catalysts were evaluated. The results show that the addition of tungsten improved the dispersion of metal nanoparticles on the support surface and thus increased the current density of Pd-based catalyst for ethanol electrooxidation. In addition, it was found that in the tungsten modified Pd-based catalyst, tungsten interacted with palladium, leading to a low onset potential and a decreased active energy for ethanol oxidation. On the other hand, it was also observed that the addition of tungsten improved the poison resistance of Pd-based catalysts for ethanol oxidation.

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PdAg/C Electrocatalysts Synthesized by Thermal Decomposition of Polymeric Precursors Improve Catalytic Activity for Ethanol Oxidation Reaction

Catalysts ◽

10.3390/catal12010096 ◽

2022 ◽

Vol 12 (1) ◽

pp. 96

Author(s):

Yonis Fornazier Filho ◽

Ana Caroliny Carvalho da Cruz ◽

Rolando Pedicini ◽

José Ricardo Cezar Salgado ◽

Rodrigo Vieira Rodrigues ◽

...

Keyword(s):

Thermal Decomposition ◽

Fuel Cells ◽

Oxidation Reaction ◽

Ethanol Oxidation ◽

Platinum Group Metal ◽

Ethanol Oxidation Reaction ◽

Polymeric Precursors ◽

Onset Potential ◽

Co Stripping ◽

Fuel Cell Performance

An efficient ethanol oxidation reaction (EOR) is required to enhance energy production in alcohol-based fuel cells. The use of bimetallic catalysts promises decreasing reliance on platinum group metal (PGM) electrocatalysts by minimizing the use of these expensive materials in the overall electrocatalyst composition. In this article, an alternative method of bimetallic electrocatalyst synthesis based on the use of polymeric precursors is explored. PdAg/C electrocatalysts were synthesized by thermal decomposition of polymeric precursors and used as the anode electrocatalyst for EOR. Different compositions, including pristine Pd/C and Ag/C, as well as bimetallic Pd80Ag20/C, and Pd60Ag40/C electrocatalysts, were evaluated. Synthesized catalysts were characterized, and electrochemical activity evaluated. X-ray diffraction showed a notable change at diffraction peak values for Pd80Ag20/C and Pd60Ag40/C electrocatalysts, suggesting alloying (solid solution) and smaller crystallite sizes for Pd60Ag40/C. In a thermogravimetric analysis, the electrocatalyst Pd60Ag40/C presented changes in the profile of the curves compared to the other electrocatalysts. In the cyclic voltammetry results for EOR in alkaline medium, Pd60Ag40/C presented a more negative onset potential, a higher current density at the oxidation peak, and a larger electrically active area. Chronoamperometry tests indicated a lower poisoning rate for Pd60Ag40/C, a fact also observed in the CO-stripping voltammetry analysis due to its low onset potential. As the best performing electrocatalyst, Pd60Ag40/C has a lower mass of Pd (a noble and expensive metal) in its composition. It can be inferred that this bimetallic composition can contribute to decreasing the amount of Pd required while increasing the fuel cell performance and expected life. PdAg-type electrocatalysts can provide an economically feasible alternative to pure PGM-electrocatalysts for use as the anode in EOR in fuel cells.

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A thiourea additive-based quadruple cation lead halide perovskite with an ultra-large grain size for efficient perovskite solar cells

Nanoscale ◽

10.1039/c9nr07377a ◽

2019 ◽

Vol 11 (45) ◽

pp. 21824-21833 ◽

Cited By ~ 9

Author(s):

Jyoti V. Patil ◽

Sawanta S. Mali ◽

Chang Kook Hong

Keyword(s):

Thin Films ◽

Grain Size ◽

Solar Cells ◽

Power Conversion Efficiency ◽

Conversion Efficiency ◽

Power Conversion ◽

Perovskite Solar Cells ◽

Inorganic Perovskite ◽

Halide Perovskite ◽

Lead Halide

Controlling the grain size of the organic–inorganic perovskite thin films using thiourea additives now crossing 2 μm size with >20% power conversion efficiency.

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