Magnetic Properties of Fe Ions in a Silicate Glass and Ceramic

Abstract

A homogeneous glass with composition 0.60SiO 2 -0.3Na 2 O-0.10Fe 2 O 3 was prepared and devitrified to produce a glass ceramic having a single crystalline phase of formula Na 5 Fe(SiO 3 ) 4 . The dc magnetic susceptibility measurements performed on the glass and the heat-treated sample have shown that the magnetic exchange interaction is antiferromagnetic and of equal strength in both samples investigated. It was shown that M versus H data at different temperatures do not collapse to a single curve in the M versus H/T representation for both the glass and the heat-treated sample, further indicating an antiferromagnetic interaction in both materials. The M versus H data for the glass sample was fitted with Brillouin function by keeping the total number of magnetic ions constant and varying the proportion of ferrous ions until a best fit was achieved. The [Fe 2+ ]/[Fe total ] concentration ratio obtained from the fit is in good agreement with the value obtained from X-ray photoelectron spectroscopy (XPS) performed on the glass sample.

Self‐Assembling of Hybrid Prussian Blue Units in Cinder Matrix: Characterization and Electrocatalysis

“…The availability of the NBO is crucial to the PB formation as will be discussed later. Although we are unable to deconvolute the Fe 2p1/2 and Fe 2p3/2 XPS peaks to various oxidation states, considering the Fe 2p3/2 BE value of 711.0 eV, the result partially validates the dominate of Fe 3 in accordance with BO as SiOFe 3 [15,16]. As to the case of derivatization and modification of the cinder, the free Fe ions bound at NBO terminals are expected to be more accessible and useful than the covalently trapped Fe ions with BO.…”

“…In silicate matrix, Fe 2 ions are more soluble and mobile than Fe 3 ions [14,15]. It is thus anticipated that Fe 3 might prefer to interact with BO and Fe 2 with NBO in the silicate matrix of cinder.…”

Electron spin resonance and magnetic studies on CaO–SiO2–P2O5–Na2O–Fe2O3 glasses

“…The superexchange interaction of the iron ions in the oxide glasses has been mostly attributed to an anti-ferromagnetic coupling within the pairs Fe 3+ -Fe 2+ , Fe 3+ -Fe 3+ and Fe 2+ -Fe 2+ [24]. An anti-ferromagnetic coupling between iron ions was reported in borate [18], phosphate [29,30], silicate [31], tellurite [25] and bismuthate [22,23] oxide glasses. In this paper, the structural changes and magnetic interactions of iron ions in CaO-SiO 2 -P 2 O 5 -Na 2 O-Fe 2 O 3 glass samples have been investigated using ESR absorption spectra and magnetic susceptibility data.…”