EPR Study of the Orientation Distribution Function of HO2 • Radicals Ordered by Light Irradiation

Chumakova, Natalia A.; Yankova, Tatiana S.; Vorobiev, Andrey Kh.

doi:10.1007/s00723-008-0047-2

Cited by 7 publications

(3 citation statements)

References 17 publications

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“…Following the notation in Ref. [15], the true distribution function can then be replaced by a f-independent effective one:…”

Section: Resultsmentioning

confidence: 99%

“…The only requirement is that the distribution of crystallites remains unchanged during the measurements, a condition certainly met in a properly restrained sample. Qualitatively similar, but more elaborated procedures are widely used in magnetic resonance techniques like EPR [15,16] and in powder diffraction [17]. We have tested the method on an SMM of the Fe4 family, namely [Fe4(L)2(dpm)6] (1) where H3L is tripodal proligand 5-(acetylthio)-2,2bis(hydroxymethyl)pentan-1-ol and Hdpm is dipivaloylmethane [18].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Unbiased evaluation of zero-field splitting D parameter in high-spin molecules from DC magnetic data with incomplete powder averaging

Cornia

Barra

Poneti

et al. 2020

Journal of Magnetism and Magnetic Materials

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“…Following the notation in Ref. [15], the true distribution function can then be replaced by a f-independent effective one:…”

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Unbiased evaluation of zero-field splitting D parameter in high-spin molecules from DC magnetic data with incomplete powder averaging

Cornia

Barra

Poneti

et al. 2020

Journal of Magnetism and Magnetic Materials

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“…In this reaction, a-SiO 2 plays a key role, thanks to its interstitial voids that absorb the excess energy of the reaction intermediate [10,11,8]. Over the years, HO 2 • radical has been studied in many materials thanks to the possibility to detect the molecule through EPR spectroscopy [12][13][14][15]. In particular, in some studies, the radical has been detected in O 2 -loaded bulk a-SiO 2 irradiated by F 2 -laser at T = 77 K [7,8].…”

Section: Introductionmentioning

confidence: 99%

Properties of HO 2 • radicals induced by γ-ray irradiation in silica nanoparticles

Buscarino

Melodia

Alessi

et al. 2014

Journal of Non-Crystalline Solids

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We report an experimental investigation on the effects of γ-ray irradiation in several types of silica nanoparticles previously loaded with O 2 molecules. They differ in specific surface and average diameter. By electron paramagnetic resonance (EPR) measurements we observe the generation of about 10 18 HO 2• /cm 3 interstitial radicals.These radicals are induced by reaction of interstitial O 2 molecules with radiolytic H atoms, as previously suggested for O 2 -loaded bulk a-SiO 2 samples. However, at variance with respect to bulk materials, our experimental evidences suggest a different generation process of HO 2 • radical. In fact, by a detailed study of samples exposed to D 2 O, our results prove that radiolytic hydrogen atoms reacting with O 2 to produce HO 2 • mainly arise from a radiation induced breaking of H 2 O molecules in the layers surrounding the nanoparticles or in the interstices. Also, by the correlation of HO 2 • paramagnetic centers concentration, determined by EPR measurements, and O 2 Raman/PL signal we further considered the issue of the direct estimation of the O 2 concentration in silica nanoparticles from Raman/PL spectra giving an independent conversion factor (the ratio between these latter two quantities), which is in good agreement with those previously proposed by other authors basing on optical measurements.

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Dual Active Intermediates Induced LiOH Formation via the OH‐Rich Proton Donor in Li−O₂ Batteries

Song,

Wang,

Wang

et al. 2024

Adv Funct Materials

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Generally, water displays a dominated impact on the solution growth mechanism of the aprotic lithium−oxygen (Li−O2) batteries, however, the high reaction activity and laborious secondary chemistry transformation process are associated with the irreversible utilization of water. In this paper, a substituted proton‐containing, highly dispersed and hydroxyl group (−OH)‐rich contained catalyst is employed in the Li−O2 battery chemistry, and lithium hydroxide (LiOH) is identified as the primary discharge product. Intriguingly, the hydrogen (H) in LiOH comes solely from the added −OH‐rich onion carbon (OLC), which is capable of building a high‐speed proton transfer bridge between the generated moieties of dual active intermediates superoxide species (O2−) and the moderate hydroperoxide (HO2−) over the platinum (Pt) active sites. The new mechanism involving the HO2− intermediate realizes a hydrogen transfer process via O2− nucleophilic attack toward OLC, which significantly suppresses the O2−‐related side reactions. Thereby, the batteries with Pt/OLC attain a high specific capacity of 12 500 mAh g−1 at a current density of 100 mA g−1, exceptional energy efficiency (100%), and remarkable rechargeability. In addition, the strong OLC‐DMSO interaction inhibits the lithium metal corrosion caused by the shuttle reactions and ensures favorable battery cycling stability. The promising results open up a new reaction pathway for Li−O2 battery electrochemistry.

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EPR Study of the Orientation Distribution Function of HO2 • Radicals Ordered by Light Irradiation

Cited by 7 publications

References 17 publications

Unbiased evaluation of zero-field splitting D parameter in high-spin molecules from DC magnetic data with incomplete powder averaging

Unbiased evaluation of zero-field splitting D parameter in high-spin molecules from DC magnetic data with incomplete powder averaging

Properties of HO 2 • radicals induced by γ-ray irradiation in silica nanoparticles

Dual Active Intermediates Induced LiOH Formation via the OH‐Rich Proton Donor in Li−O₂ Batteries

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EPR Study of the Orientation Distribution Function of HO2 • Radicals Ordered by Light Irradiation

Cited by 7 publications

References 17 publications

Unbiased evaluation of zero-field splitting D parameter in high-spin molecules from DC magnetic data with incomplete powder averaging

Unbiased evaluation of zero-field splitting D parameter in high-spin molecules from DC magnetic data with incomplete powder averaging

Properties of HO 2 • radicals induced by γ-ray irradiation in silica nanoparticles

Dual Active Intermediates Induced LiOH Formation via the OH‐Rich Proton Donor in Li−O2 Batteries

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Product

Resources

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Dual Active Intermediates Induced LiOH Formation via the OH‐Rich Proton Donor in Li−O₂ Batteries