Preparation of Highly Active Noble Metal Phosphide Catalysts: Effect of Precursors on the Formation of the Active Phase and Hydrodesulfurization Activity

The transition metals V, Cr, Mn, Fe, Co, Ni, Mo, Ru, Rh, Pd, W, Re, Os, Ir and Pt were deposited from aqueous solutions of their salts onto conventional γ-Al2O3 and unconventional TiO2 and ZrO2 supports by vacuum impregnation and characterized in their sulfided form by a model reaction of benzothiophene hydrodesulfurization. It was found that the TiO2 and ZrO2 supports influenced predominantly positively the resulting activity of relatively low-active metals (V, Cr, Mn, Fe, Co, Ni, Mo, Ru, W and Os), whereas the highly active metals (Rh, Pd, Ir, Pt and Re) were influenced slightly negatively or not at all by those supports compared with the γ-Al2O3-supported system. A significant effect of the supports on the hydrodesulfurization-activity ranking of the transition-metal sulfides studied was ascertained.

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Multifunctional Noble Metal Phosphide Electrocatalysts for Organic Molecule Electro-Oxidation

ACS Applied Energy Materials ◽

10.1021/acsaem.0c02803 ◽

2021 ◽

Vol 4 (2) ◽

pp. 1593-1600 ◽

Cited By ~ 1

Author(s):

Zhipeng Yu ◽

Xian-Kui Wei ◽

Junyuan Xu ◽

Yue Li ◽

Ana Araujo ◽

...

Keyword(s):

Noble Metal ◽

Organic Molecule ◽

Metal Phosphide ◽

Electro Oxidation

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Enhancement of photocatalytic performance with the use of noble-metal-decorated TiO 2 nanocrystals as highly active catalysts for aerobic oxidation under visible-light irradiation

Applied Catalysis B Environmental ◽

10.1016/j.apcatb.2017.03.077 ◽

2017 ◽

Vol 210 ◽

pp. 352-367 ◽

Cited By ~ 55

Author(s):

Yu Chen ◽

Yannan Wang ◽

Weizun Li ◽

Qian Yang ◽

Qidong Hou ◽

...

Keyword(s):

Visible Light ◽

Noble Metal ◽

Visible Light Irradiation ◽

Photocatalytic Performance ◽

Aerobic Oxidation ◽

Light Irradiation ◽

Highly Active

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Surfactant-Free Colloidal Strategies for Highly Dispersed and Active Supported IrO2 Catalysts: Synthesis and Performance Evaluation for the Oxygen Evolution Reaction

10.26434/chemrxiv.13643807.v1 ◽

2021 ◽

Author(s):

Francesco Bizzotto ◽

Jonathan Quinson ◽

Johanna Schröder ◽

Alessandro Zana ◽

Matthias Arenz

Keyword(s):

Supported Catalysts ◽

Active Phase ◽

Carbon Support ◽

Colloidal Dispersions ◽

Catalyst Design ◽

Transition Electron Microscopy ◽

Highly Active ◽

X Ray Scattering ◽

And Performance ◽

Transition Electron

Supported Ir oxide catalysts obtained from surfactant-free colloidal Ir nanoparticles (NPs) synthesized in alkaline methanol (MeOH), ethanol (EtOH), and ethylene glycol (EG) are investigated and compared. The comparison of independent techniques such as transition electron microscopy (TEM), small angle X-ray scattering (SAXS), and electrochemistry allows shedding light on the parameters that affect the dispersion of the active phase as well as the catalytic activity. The colloidal dispersions obtained are suitable to develop supported catalysts with little NP agglomeration on a carbon support leading to highly active catalysts with more than 400 A g-1Ir reached at 1.5 VRHE for the OER. While the more common surfactant-free alkaline EG synthesis requires flocculation and re-dispersion leading to Ir loss, the main difference between methanol and ethanol as solvent is related to the dispersibility of the support material. The choice of the suitable monoalcohol determines the maximum achieved Ir loading on the support without detrimental particle agglomeration. This simple consideration on catalyst design can readily lead to significantly improved catalysts.

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Silica-confined Ru highly-dispersing on ZrO2 with enhanced activity and thermal stability in dichloroethane combustion

Nanoscale ◽

10.1039/d1nr01538a ◽

2021 ◽

Author(s):

Zhaoyang Fei ◽

Zhicheng Wang ◽

Dunfei Li ◽

Fan Xue ◽

Chao Cheng ◽

...

Keyword(s):

Thermal Stability ◽

Noble Metal ◽

Core Shell ◽

Spontaneous Deposition ◽

Efficient Strategy ◽

Highly Active ◽

Enhanced Activity ◽

Metal Sintering ◽

Thermal Stable

An efficient strategy (spontaneous deposition to enhance noble metal dispersity and core-shell confinement to inhibit the noble metal sintering) is presented to synthesize highly active and thermal stable Ru/ZrO2@SiO2 catalyst...

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Nitrogen-Doped Sponge Ni Fibers as Highly Efficient Electrocatalysts for Oxygen Evolution Reaction

Nano-Micro Letters ◽

10.1007/s40820-019-0253-5 ◽

2019 ◽

Vol 11 (1) ◽

Cited By ~ 19

Author(s):

Kaili Zhang ◽

Xinhui Xia ◽

Shengjue Deng ◽

Yu Zhong ◽

Dong Xie ◽

...

Keyword(s):

Oxygen Evolution ◽

Photoelectron Spectroscopy ◽

Oxygen Evolution Reaction ◽

Active Sites ◽

High Performance ◽

Active Phase ◽

X Ray ◽

Highly Active ◽

N Doping ◽

Energy Conversion Devices

Abstract Controllable synthesis of highly active micro/nanostructured metal electrocatalysts for oxygen evolution reaction (OER) is a particularly significant and challenging target. Herein, we report a 3D porous sponge-like Ni material, prepared by a facile hydrothermal method and consisting of cross-linked micro/nanofibers, as an integrated binder-free OER electrocatalyst. To further enhance the electrocatalytic performance, an N-doping strategy is applied to obtain N-doped sponge Ni (N-SN) for the first time, via NH3 annealing. Due to the combination of the unique conductive sponge structure and N doping, the as-obtained N-SN material shows improved conductivity and a higher number of active sites, resulting in enhanced OER performance and excellent stability. Remarkably, N-SN exhibits a low overpotential of 365 mV at 100 mA cm−2 and an extremely small Tafel slope of 33 mV dec−1, as well as superior long-term stability, outperforming unmodified sponge Ni. Importantly, the combination of X-ray photoelectron spectroscopy and near-edge X-ray adsorption fine structure analyses shows that γ-NiOOH is the surface-active phase for OER. Therefore, the combination of conductive sponge structure and N-doping modification opens a new avenue for fabricating new types of high-performance electrodes with application in electrochemical energy conversion devices.

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Room temperature hydrogen generation from aqueous ammonia-borane using noble metal nano-clusters as highly active catalysts

Journal of Power Sources ◽

10.1016/j.jpowsour.2007.03.015 ◽

2007 ◽

Vol 168 (1) ◽

pp. 135-142 ◽

Cited By ~ 388

Author(s):

Manish Chandra ◽

Qiang Xu

Keyword(s):

Noble Metal ◽

Room Temperature ◽

Hydrogen Generation ◽

Aqueous Ammonia ◽

Ammonia Borane ◽

Highly Active

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Nanocarbon-intercalated and Fe–N-codoped graphene as a highly active noble-metal-free bifunctional electrocatalyst for oxygen reduction and evolution

Journal of Materials Chemistry A ◽

10.1039/c5ta09232a ◽

2017 ◽

Vol 5 (5) ◽

pp. 1930-1934 ◽

Cited By ~ 62

Author(s):

Daping He ◽

Yuli Xiong ◽

Jinlong Yang ◽

Xu Chen ◽

Zhaoxiang Deng ◽

...

Keyword(s):

Oxygen Reduction ◽

Noble Metal ◽

Bifunctional Electrocatalyst ◽

Metal Free ◽

Highly Active

A highly active bifunctional electrocatalyst for oxygen reduction and evolution reactions was developed based on nanocarbon-intercalated and Fe–N-codoped graphene materials.

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Highly Active Trifloaluminate Ionic Liquids as Recyclable Catalysts for Green Oxidation of 2,3,6-Trimethylphenol to Trimethyl-1,4-Benzoquinone

Catalysts ◽

10.3390/catal10121469 ◽

2020 ◽

Vol 10 (12) ◽

pp. 1469

Author(s):

Piotr Latos ◽

Agnieszka Siewniak ◽

Natalia Barteczko ◽

Sebastian Jurczyk ◽

Sławomir Boncel ◽

...

Keyword(s):

Aqueous Solution ◽

Ionic Liquids ◽

High Selectivity ◽

Active Phase ◽

Catalytic Performance ◽

Reaction Parameters ◽

Multiwalled Carbon ◽

Highly Active ◽

Recyclable Catalysts ◽

Fold Excess

An effective method for the synthesis of 2,3,6-trimethyl-1,4-benzoquinone via the oxidation of 2,3,6-trimethylphenol as the key step in the in the preparation of vitamin E was presented. An aqueous solution of H2O2 was used as the oxidant and Lewis acidic trifloaluminate ionic liquids [emim][OTf]-Al(OTf)3, χAl(OTf)3 = 0.25 or 0.15 as catalysts. Trifloaluminate ionic liquids were synthesised by the simple reaction between 1-ethyl-3-methylimidazolium trifluoromethanesulfonate (triflate) [emim][OTf] and aluminium triflate used in sub-stoichiometric quantities. The influence of the reaction parameters on the reaction course, such as the amount and concentration of the oxidant, the amount of catalyst, the amount and the type of organic solvent, temperature, and the reaction time was investigated. Finally, 2,3,6-trimethyl-1,4-benzoquinone was obtained in high selectivity (99%) and high 2,3,6-trimethylphenol conversion (84%) at 70 °C after 2 h of oxidation using a 4-fold excess of 60% aqueous H2O2 and acetic acid as the solvent. The catalytic performance of trifloaluminate ionic liquids supported on multiwalled carbon nanotubes (loading of active phase: 9.1 wt.%) was also demonstrated. The heterogeneous ionic liquids not only retained their activity compared to the homogenous counterparts, but also proved to be a highly recyclable catalysts.

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