Elucidating the Role of Catalyst Steric and Electronic Effects in Controlling the Synthesis of π-Conjugated Polymers

The role of steric and electronic effects during the rate and product determining steps for the addition of arenesulphenyl chlorides to 1,3-disubstituted allenes has been briefly examined. Both effects appear to be generally of minimal importance during the rate determining step. The available rate data indicate the presence of little, if any, build up of positive charge on sulphur. These results are interpreted in terms of an SN2 attack on bivalent sulphur leading to an alkylidenethiiranium ion intermediate. Steric effects are of greater importance in the product determining step, particularly when the sulphenyl chlorides possess two bulky ortho substituents, as in the case of 2,4,6-triisopropylbenzenesulphenyl chloride.

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The role of impurities on the electron paramagnetic resonance response of polarons in conjugated polymers.

Synthetic Metals ◽

10.1016/s0379-6779(96)04195-1 ◽

1997 ◽

Vol 84 (1-3) ◽

pp. 885-886 ◽

Cited By ~ 4

Author(s):

Francesco P. Orfino ◽

Steven Holdcroft

Keyword(s):

Electron Paramagnetic Resonance ◽

Conjugated Polymers ◽

Paramagnetic Resonance ◽

Resonance Response ◽

Electron Paramagnetic

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The role of electronic effects in determining the thermodynamic stabilities of olefin complexes of palladium(II) and platinum(II)

Journal of the Chemical Society Chemical Communications ◽

10.1039/c39730000591 ◽

1973 ◽

pp. 591 ◽

Cited By ~ 7

Author(s):

Eva M. Ban ◽

Russell P. Hughes ◽

John Powell

Keyword(s):

Electronic Effects

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On the Role of the Coulomb Interaction in Conjugated Polymers

Springer Series in Solid-State Sciences - Electronic Properties of Conjugated Polymers ◽

10.1007/978-3-642-83284-0_35 ◽

1987 ◽

pp. 198-203 ◽

Cited By ~ 2

Author(s):

D. Baeriswyl

Keyword(s):

Conjugated Polymers ◽

Coulomb Interaction

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Fe-Doping in Double Perovskite PrBaCo2(1-x)Fe2xO6-δ: Insights into Structural and Electronic Effects to Enhance Oxygen Evolution Catalyst Stability

Catalysts ◽

10.3390/catal9030263 ◽

2019 ◽

Vol 9 (3) ◽

pp. 263 ◽

Cited By ~ 9

Author(s):

Bae-Jung Kim ◽

Emiliana Fabbri ◽

Ivano Castelli ◽

Mario Borlaf ◽

Thomas Graule ◽

...

Keyword(s):

Oxygen Evolution ◽

Oxygen Evolution Reaction ◽

Double Perovskite ◽

Alkaline Media ◽

Catalyst Stability ◽

Electronic Effects ◽

Single Transition ◽

Charge Stability ◽

X Ray Absorption

Perovskite oxides have been gaining attention for its capability to be designed as an ideal electrocatalyst for oxygen evolution reaction (OER). Among promising candidates, the layered double perovskite—PrBaCo2O6-δ (PBC)—has been identified as the most active perovskite electrocatalyst for OER in alkaline media. For a single transition metal oxide catalyst, the addition of Fe enhances its electrocatalytic performance towards OER. To understand the role of Fe, herein, Fe is incorporated in PBC in different ratios, which yielded PrBaCo2(1-x)Fe2xCo6-δ (x = 0, 0.2 and 0.5). Fe-doped PBCF’s demonstrate enhanced OER activities and stabilities. Operando X-ray absorption spectroscopy (XAS) revealed that Co is more stable in a lower oxidation state upon Fe incorporation by establishing charge stability. Hence, the degradation of Co is inhibited such that the perovskite structure is prolonged under the OER conditions, which allows it to serve as a platform for the oxy(hydroxide) layer formation. Overall, our findings underline synergetic effects of incorporating Fe into Co-based layered double perovskite in achieving a higher activity and stability during oxygen evolution reaction.

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