Surface-enhanced Raman spectra of magnetic nanoparticles adsorbed on a silver electrode

Jacintho, Guilherme V. M.; Cório, Paola; Rubim, Joel C.

doi:10.1016/j.jelechem.2007.02.019

Cited by 43 publications

(44 citation statements)

References 47 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The γ‐Fe 2 O 3 nanoparticles in the aqueous electrolyte are covered by a shell of Fe hydroxides, essentially ferroxyhite (δ‐FeOOH), which is reduced to magnetite (Fe 3 O 4 ) upon cathodic scan. Fe hydroxides are formed again by reoxidation upon anodic scan 14. Such kind of surface reaction, i.e., oxidation of Fe 3 O 4 to δ‐FeOOH upon positive charging, would be in qualitative agreement with the present observation that the magnetic moment decreases with positive charging, because the specific magnetization of δ‐FeOOH (<10 emu g –1 ) is much smaller than that of Fe 3 O 4 (90 emu g –1 ).…”

Section: Discussionsupporting

confidence: 89%

“…Literature on such reactions of γ‐Fe 2 O 3 is rare. According to Jacintho et al, nanoparticles of γ‐Fe 2 O 3 adsorbed on a silver electrode in an aqueous electrolyte may undergo electrochemical reactions at the surface 14. The γ‐Fe 2 O 3 nanoparticles in the aqueous electrolyte are covered by a shell of Fe hydroxides, essentially ferroxyhite (δ‐FeOOH), which is reduced to magnetite (Fe 3 O 4 ) upon cathodic scan.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Magnetization of Fe‐oxide based nanocomposite tuned by surface charging

Traußnig

Topolovec

Nadeem

et al. 2011

Physica Rapid Research Ltrs

View full text Add to dashboard Cite

Aiming at a voltage‐control of magnetism, the magnetization of a porous γ‐Fe2O3–Pt nanocomposite is studied under the influence of charging the surfaces of the porous structure in an electrolyte. Reversible variations of the magnetization of up to 10.4% could be achieved upon charging in the regime where electrochemical adsorption and desorption occurs. The observed variation of the magnetization with electrochemical charging is assigned to the γ‐Fe2O3 nanoparticles whereas the conductive network of Pt nanoparticles is necessary for charging. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

show abstract

Section: Discussionsupporting

confidence: 89%

Section: Discussionmentioning

confidence: 99%

Magnetization of Fe‐oxide based nanocomposite tuned by surface charging

Traußnig

Topolovec

Nadeem

et al. 2011

Physica Rapid Research Ltrs

View full text Add to dashboard Cite

show abstract

“…The peak that corresponds to Fe 2 Pi ss ignificantly reduced relative to that of the catalystp rior to the polarization experiments,w hich suggestst hat an ew active ironbased species is generated duringt he OERp rocess. As shown in Figure S5, bands situated at 262 and 509 cm À1 and the strong bands at 715 and 377 cm À1 can be indexed to a-FeOOH, b-FeOOH, and g-FeOOH, [83,84] and the weak bands at 301, 530, 661, and 388 cm À1 are causedb yF e 3 O 4 and a-Fe 2 O 3 ; [85,86] only as mall band at 488 cm À1 pertainingt oF e 3 P [87] can be found, which confirms the formation and coexistence of M 2 O 3 ,M 3 O 4 ,a nd M(O)OH( M= Fe, Mn) during the OER process. The contact conditions between the catalyst and electrolyte are ac ritical factor affecting the catalytic performance.…”

Section: Resultsmentioning

confidence: 97%

Free‐Sustaining Three‐Dimensional S235 Steel‐Based Porous Electrocatalyst for Highly Efficient and Durable Oxygen Evolution

et al. 2018

View full text Add to dashboard Cite

A novel oxygen evolution reaction (OER) catalyst (3 D S235-P steel) based on a steel S235 substrate was successfully prepared by facile one-step surface modification. The standard carbon-manganese steel was phosphorized superficially, which led to the formation of a unique 3 D interconnected nanoporous surface with a high specific area that facilitated the electrocatalytically initiated oxygen evolution reaction. The prepared 3 D S235-P steel exhibited enhanced electrocatalytic OER activities in the alkaline regime, as confirmed by a low overpotential (326 mV at a 10 mA cm ) and a small Tafel slope of 68.7 mV dec . Moreover, the catalyst was found to be stable under long-term usage conditions, functioning as an oxygen-evolving electrode at pH 13, as evidenced by the sufficient charge-to-oxygen conversion rate (faradaic efficiency: 82.11 and 88.34 % at 10 and 5 mA cm , respectively). In addition, it turned out that the chosen surface modification delivered steel S235 as an OER electrocatalyst that was stable under neutral pH conditions. Our investigation revealed that the high catalytic activities likely stemmed from the generated Fe/(Mn) hydroxide/oxohydroxides generated during the OER process. Phosphorization treatment therefore not only is an efficient way to optimize the electrocatalytic performance of standard carbon-manganese steel but also enables for the development of low-costing and abundant steels in the field of energy conversion.

show abstract

“…One of profitable methods for Fe speciation in Fe-modified aluminosilicates is their voltammetric analysis [2,6,7,9,13,14]. The electroanalysis of Fe species is based on several phase-specific electrochemical processes [15][16][17], particularly on the reduction of Fe(III) solids to soluble Fe 2+ ions [18][19][20][21].…”

Section: Introductionmentioning

confidence: 99%