Structural and transport properties of La1−xAgxMnO3 (x=0.075, 0.1, 0.125 and 0.15) manganites

Shaikh, M. W.; Mansuri, Irfan; Dar, M. A.; Varshney, Dinesh

doi:10.1016/j.mssp.2015.02.061

Cited by 20 publications

(12 citation statements)

References 67 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A similar suggestion was also proposed for Nd0.5Ca0.5Mn1-xCrxO3 [15]. Apart from that, the substitution of Cr 3+ was also suggested to induce the lattice distortion and rearrangement of atom as a results of smaller cation in the B-site of the ABO3 perovskite structure is responsible for the reduction in unit cell volume [17][18][19]. Fig.…”

Section: Methodssupporting

confidence: 67%

Enhancement of Double-Exchange Mechanism in Charge-Ordered Pr0.75Na0.25MnO3 Ceramics by Cr Doped at Mn-Site

Zawawi¹,

Ibrahim²,

Shamsuddin³

2018

IJCRSET

View full text Add to dashboard Cite

Charge ordered Pr0.75Na0.25Mn1-xCrxO3 (x = 0-0.04) ceramics has been investigated to study the effect of Cr doping on structure and electrical transport properties as well as surface morphology which synthesized using the solid-state reaction method. X-ray diffraction (XRD) analysis revealed the crystalline phase of all samples consists of essentially single phase and crystallized in an orthorhombic structure. The Cr doping were influence the lattice parameters and the unit cell volume suggestively due to the different of ionic radius between Mn 3+ ions and Cr 3+ ions. DC electrical resistance measurement showed that, the x = 0 sample exhibited an insulating behaviour down to the lower temperature. Interestingly, the metal-insulator (MI) transition temperature for x = 0.02 and x = 0.04 samples were found to be around TMI~120 K and TMI~122 K respectively indicating the enhancement of double-exchange (DE) mechanism as a result of weakening the Jahn-Teller (JT) effect which caused the charge ordered (CO) state to be weakened. scanning electron microscope (SEM) images of Pr0.75Na0.25Mn1-xCrxO3 compound showed the morphology of the samples were quite uniform suggestively due to the good crystalline nature.

show abstract

Section: Methodssupporting

confidence: 67%

Enhancement of Double-Exchange Mechanism in Charge-Ordered Pr0.75Na0.25MnO3 Ceramics by Cr Doped at Mn-Site

Zawawi¹,

Ibrahim²,

Shamsuddin³

2018

IJCRSET

View full text Add to dashboard Cite

show abstract

“…The A‐site substitution by Ag gives rise to various competitions between structural, magnetic and electronic phases, leading to interesting transport properties . The charge‐carrier density rises with increasing Ag dopant concentration, confirmed by the increased conductivity of about 10 0 S cm −1 for La 0.85 Ag 0.15 MnO 3 (LAMO); LAMO exhibits half‐metallic ferromagnetism at T C close to room temperature . To the best of our knowledge, no literature study has compared the ORR activity of LAMO with LSMO, nor with any of the several FM manganese conductors with perovskite structure with high T C reported by Jonker and van Santen .…”

Section: Resultsmentioning

confidence: 99%

Analysis of the Magnetic Entropy in Oxygen Reduction Reactions Catalysed by Manganite Perovskites

Gracia¹,

Munárriz

Polo

et al. 2017

ChemCatChem

View full text Add to dashboard Cite

Manganese oxides with a half‐metallic ground state are particularly active for oxygen reduction reactions (ORR). La0.67Sr0.33MnO3 (LSMO) perovskite is the archetypal example for compositions with a Curie temperature (TC) above room temperature and with a high intrinsic activity for the partial reduction of triplet‐state O2. The ferromagnetic (FM) character of the superexchange interactions in LSMO facilitates both charge and spin transport below 370 K. Other than the enhanced electronic conductivity, the reduced spin entropy seems to be relevant in oxygen catalysis because the magnetic ordering extends to the surface. The sign of the exchange interactions determines the adsorption of the triplet oxygen molecule with its spin antiparallel to the FM catalysts. Based on the transition‐state theory, we report that on LSMO, the hindrance resulting from the magnetic entropy for the initial reduction of O2 by two antiparallel electrons to diamagnetic intermediates (such H2O2) is minimum. On the other hand, the additional reduction of H2O2 to H2O, diamagnetic steps, prefers paramagnetic catalysts with higher magnetic entropy such as La0.4Sr0.6MnO3 to avoid spin accumulation.

show abstract

“…When an aqueous solution consist of photocatalyst, air or oxygen, and MB as organic contaminant irradiated under UV or visible light (hυ), then electron-hole pairs would be produced (equation (5)). These photogenerated electron-hole pairs are powerful reducing and oxidizing agents, respectively.…”

Section: Photocatalysis Mechanismmentioning

confidence: 99%

“…This substitution modifies the structure by rotating the MnO 6 octahedral as well as changing the Mn-O-Mn bond length and angle. Many theories like the Jahn Teller (JT) distortion and the double exchange (DE) mechanism are introduced to explain this phenomenon [5]. The properties of La 1−x A x MnO 3 perovskite-type oxides are related to their stoichiometry and degree of substitution of the alkaline element for La [6].…”

Section: Introductionmentioning

confidence: 99%

Synthesis and characterization of calcium-doped lanthanum manganite nanowires as a photocatalyst for degradation of methylene blue solution under visible light irradiation

2018

View full text Add to dashboard Cite

Calcium-doped lanthanum manganite (LCMO) powder was synthesized via hydrothermal method. The structural, morphological and optical properties of the resulting powder was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), inductively coupled plasma-atomic emission spectroscopy (ICP-AES spectrometer), field emission scanning electron microscopy (FESEM) and UV-Vis spectroscopy (UV-Vis). The XRD results showed the existence of only one crystalline phase. FESEM image indicates that the LCMO sample has nanowire structure with an average diameter of ∼125 nm. The band gap energy of the sample was about 2.13 eV. The as-prepared nanowires showed sufficient visible-light photocatalytic activity for the water treatment from dyes and toxic organic materials. The photodegradation efficiency for decolourizing methylene blue solution (7 ppm) by LCMO nanowires (0.07g l −1), after 360 min illumination, was about 73% with a reaction rate constant of 0.003 min −1. The six times cycled results suggested the great long-term stability of the photocatalyst.

show abstract

Structural and transport properties of La1−xAgxMnO3 (x=0.075, 0.1, 0.125 and 0.15) manganites

Cited by 20 publications

References 67 publications

Enhancement of Double-Exchange Mechanism in Charge-Ordered Pr0.75Na0.25MnO3 Ceramics by Cr Doped at Mn-Site

Enhancement of Double-Exchange Mechanism in Charge-Ordered Pr0.75Na0.25MnO3 Ceramics by Cr Doped at Mn-Site

Analysis of the Magnetic Entropy in Oxygen Reduction Reactions Catalysed by Manganite Perovskites

Synthesis and characterization of calcium-doped lanthanum manganite nanowires as a photocatalyst for degradation of methylene blue solution under visible light irradiation

Contact Info

Product

Resources

About