Synthesis of Undoped and Manganese-Doped HgTe Nanoparticles Using [Hg(TeCH2CH2NMe2)2] as a Single Source Precursor

The Reaction of [HgCl2(tmeda)] with NaTeCH2CH2NMe2 gave a mercury tellurolate, [Hg(TeCH2CH2·NMe2)2] (1) as a yellow crystalline solid, which was characterized by elemental analysis, UV-vis, mass and NMR (1H, 13C, 125Te, 199Hg) spectroscopy. Thermolysis of 1 in hexadecylamine (HDA) at 90 °C in the absence and presence of Mn(OAc)2·4H2O gave undoped and Mn-doped HgTe nanoparticles which were characterized by XRD, EDAX, TEM, EPR and magnetic measurements. These particles could be synthesized with mean particle size of 6–7 nm (from TEM). Manganese substitution at Hg site in HgTe lead to a linear decrease in lattice parameter with increasing concentration of Mn. Magnetization measurements showed ferromagnetic ordering at room temperature with very small coercive field (Hc, 50 Oe) for Hg0.973Mn0.027 Te sample. This sample also exhibited distinct ferromagnetic resonance (FMR) in the EPR spectrum.

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Hydrothermal Synthesis of CoFe2O4 Nanoparticles and their Magnetic Properties

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.821-822.1358 ◽

2013 ◽

Vol 821-822 ◽

pp. 1358-1361 ◽

Cited By ~ 2

Author(s):

Fan Zhang ◽

Rui Liang Su ◽

Li Zhi Shi ◽

Yang Liu ◽

Yan Na Chen ◽

...

Keyword(s):

Particle Size ◽

Magnetic Properties ◽

Room Temperature ◽

Magnetic Measurements ◽

Spinel Ferrite ◽

Synthesis Method ◽

Ferrite Nanoparticles ◽

Particle Sizes ◽

Naoh Solution ◽

20 Nm

CoFe2O4 (CFO) nanoparticles was synthesized by a simple hydrothermal method using NaOH solution as a mineralizer at 200 °C for 4 h. It was found that CFO particle sizes decreased firstly and then increased with the increasing of NaOH concentration, and had a minumum value about 10-20 nm when selected 4 mol/L NaOH solution, indicating the NaOH concentration played an important role in controlling the particle size of CFO powders. The room temperature magnetic measurements showed that the saturation magnetization value was 48 emu/g, which is less than the bulk value. The synthesis method is possible to be a general approach for the preparation of other spinel ferrite nanoparticles.

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Magneto-Opto Electronic Applications of Conductive and Room Temperature Ferromagnetic (Al, Mn) Co-Doped ZnO Particles with Visible Emission

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2020.17497 ◽

2020 ◽

Vol 20 (6) ◽

pp. 3913-3918 ◽

Cited By ~ 1

Author(s):

Divya Rehani ◽

Swati Bishnoi ◽

Manish Saxena ◽

Shailesh Narain Sharma

Keyword(s):

Room Temperature ◽

Annealing Temperature ◽

Magnetic Measurements ◽

Hexagonal Wurtzite Structure ◽

Solid State Reaction Method ◽

Ferromagnetic Behavior ◽

Maximum Conductivity ◽

Doped Zno ◽

Mn Doped ◽

Co Doped

The Mn, Al co-doped ZnO samples were synthesized using solid-state reaction method and were annealed in furnace at 300 °C, 600 °C and 900°C temperature. All the samples prepared were investigated in detail for analysis of their structural, morphological, optical, magnetic and electrical behavior. The XRD data confirmed the hexagonal wurtzite structure of pristine, Mn doped and Al, Mn co-doped ZnO. For morphological investigation SEM and TEM techniques were employed. The PL properties of the ZnO:Mn, Al sample revealed emission in the blue region (415–438 nm). Furthermore, IV studies were carried out to examine the conductivity of the ZnO:Mn, Al samples and maximum conductivity was found in the sample with 5% Al doping and annealing temperature 600 °C. The magnetic measurements revealed room temperature ferromagnetic behavior in the optimized ZnO:Mn, Al sample annealed at 600 °C which indicates its suitability for Magneto-Opto Electronic Applications.

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Graphene oxide grafted with Pd17Se15 nano-particles generated from a single source precursor as a recyclable and efficient catalyst for C–O coupling in O-arylation at room temperature

Chemical Communications ◽

10.1039/c3cc42608d ◽

2013 ◽

Vol 49 (68) ◽

pp. 7483 ◽

Cited By ~ 48

Author(s):

Hemant Joshi ◽

Kamal Nayan Sharma ◽

Alpesh K. Sharma ◽

Om Prakash ◽

Ajai Kumar Singh

Keyword(s):

Graphene Oxide ◽

Room Temperature ◽

Nano Particles ◽

Single Source ◽

Efficient Catalyst ◽

Single Source Precursor

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Suppression of Ferromagnetic Ordering in thicker co-sputtered Mn doped MgO Films

MRS Proceedings ◽

10.1557/opl.2013.611 ◽

2013 ◽

Vol 1552 ◽

pp. 83-88 ◽

Cited By ~ 1

Author(s):

Sreekanth K. Mahadeva ◽

Zhi-Yong Quan ◽

J. C. Fan ◽

K. S. Sreelatha ◽

L. Belova ◽

...

Keyword(s):

Magnetic Properties ◽

Film Thickness ◽

Saturation Magnetization ◽

Room Temperature ◽

Structural Surface ◽

Ferromagnetic Ordering ◽

Surface Morphologies ◽

Mn Doped ◽

Different Thickness

ABSTRACTWe report on preliminary studies of low (14 at.%) and high (53at.%) concentration Mn doped MgO films deposited by co-sputtering from metallic Mn and Mg targets. The structural, surface morphologies and magnetic properties of the films of different thickness were studied. All the as grown films are found to be amorphous and film surfaces are found to be flawless and homogeneous. We observe at room temperature robust ferromagnetic loops with a saturation magnetization value that is a function of film thickness reaching a maximum of ∼38.5 emu/cm3 in the Mn0.53Mg0.47O film at a thickness of ∼92 nm. In thicker films room-temperature ferromagnetic ordering is suppressed and eventually at a thickness around 120nm the expected diamagnetism of the bulk appears. The origin of ferromagnetism may be attributed to cation defects at the Mg-site.

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Bimetallic single-source precursor for the synthesis of pure nanocrystalline room temperature-stabilized β-NiMoO 4

Ceramics International ◽

10.1016/j.ceramint.2015.09.076 ◽

2016 ◽

Vol 42 (1) ◽

pp. 1366-1372 ◽

Cited By ~ 3

Author(s):

Ahmed M. Moneeb ◽

Abdullah M. Alabdulrahman ◽

Abdulaziz A. Bagabas ◽

Cory K. Perkins ◽

Allen W. Apblett

Keyword(s):

Room Temperature ◽

Single Source ◽

Single Source Precursor

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ENHANCED MAGNETIZATION IN COBALT SUBSTITUTED Ni–Zn NANOFERRITES

International Journal of Nanoscience ◽

10.1142/s0219581x1100909x ◽

2011 ◽

Vol 10 (04n05) ◽

pp. 571-576 ◽

Cited By ~ 3

Author(s):

M. CHAITANYA VARMA ◽

A. MAHESH KUMAR ◽

K. H. RAO

Keyword(s):

Particle Size ◽

Room Temperature ◽

Sol Gel ◽

Chelating Agent ◽

Lattice Parameter ◽

Line Broadening ◽

X Ray Diffraction ◽

Chemical Methods ◽

X Ray ◽

Nickel Zinc

Cobalt substituted nickel zinc ferrite nanoparticles ( Ni 0.65–x Co x Zn 0.35 Fe 2.0 O 4) X varying from 0.0 to 0.65 in steps of 0.15 have been produced using sol–gel method, with PVA as chelating agent. The phase formation of the sintered ferrite was confirmed by X-ray diffraction studies. The lattice parameter a(A°) has been calculated using Nelson–Riley method. The crystallite size has been estimated by the Williamson–Hall method using the full width at half-maximum (FWHM) of the line broadening of all the peaks. Mössbauer spectroscopy (MS) of the samples showed the clear presence of two sextets and distribution of iron over the two sites has been given. Increase in saturation magnetization with cobalt concentration with a slight decrease for x = 0.15 has been observed with the vibrating sample magnetometry study. The observed value of magnetization for Ni0.65Zn0.35Fe2O4 with a particle size of 43.5 nm has been 71 emu/gm at room temperature, which is higher than that reported for samples prepared using chemical methods of the same composition. The results have been explained on the basis of the particle size and cation distribution among various sites.

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ROOM TEMPERATURE FERROMAGNETISM IN Mn DOPED ZnO SEMICONDUCTOR

International Journal of Modern Physics B ◽

10.1142/s0217979209052133 ◽

2009 ◽

Vol 23 (08) ◽

pp. 2029-2040 ◽

Cited By ~ 3

Author(s):

R. K. SINGHAL ◽

S. N. DOLIA ◽

M. S. DHAWAN ◽

S. K. GAUR ◽

SUDHISH KUMAR ◽

...

Keyword(s):

Magnetic Properties ◽

Room Temperature ◽

Room Temperature Ferromagnetism ◽

Recent Past ◽

Doped Zno ◽

Ferromagnetic Ordering ◽

Mn Doped ◽

Zno Semiconductor ◽

Ferromagnetic Contribution ◽

Co Doped

Following the theoretical prediction of ferromagnetism in Mn - and Co -doped ZnO , there has been an immense experimental search for dilute semiconductors that show ferromagnetic ordering above room temperature, and several workers have reported ferromagnetism in bulk samples as well as in thin films of these materials. Mn -doped ZnO is the key material in this regard, which has been, in the recent past, shown to exhibit such magnetic properties. Many more such attempts have either led to failure or to a much lower Tc, and there have been a lot of confronting reports casting considerable doubts on the magnetism in this system. In order to shed some light, we have prepared and characterized dilute Mn -doped (2 and 4%) ZnO pellets. SQUID measurements confirm that the 2% sample shows above room temperature ferromagnetic ordering, the ferromagnetic contribution coming mainly from the bulk. The ordering gets completely quenched for 4% Mn doping. Upon cooling down, the 2% Mn doped sample showed further enhancement in magnetic properties appreciably. On the other hand, the 4% sample did not show any ferromagnetic ordering, even down to 5 K, and has been found to retain the paramagnetic character.

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A Facile Route for the Synthesis of Poly(N-vinylcarbazole)/Manganese Sulphide Quantum Dots Nanocomposites with Enhanced Optical Properties

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2008.485 ◽

2008 ◽

Vol 8 (11) ◽

pp. 6031-6037 ◽

Cited By ~ 2

Author(s):

Nosipho Moloto ◽

Suprakas Sinha Ray ◽

Makwena Justice Moloto

Keyword(s):

Quantum Dots ◽

Optical Properties ◽

Electron Microscope ◽

Elevated Temperature ◽

Room Temperature ◽

Single Source ◽

Precursor Method ◽

Tetramethylthiuram Disulfide ◽

Single Source Precursor ◽

Facile Route

This communication describes a facile route for the synthesis of manganese sulphide (MnS) quantum dots (QDs) contained in poly(N-vinyl carbazole) (PNVC) nanocomposites. MnS QDs were synthesized using the single-source precursor method by thermolysing tetramethylthiuram disulfide manganese complex in hexadecylamine (HDA). Two different methods were used for the synthesis of MnS QD incorporated PNVC nanocomposites. The first method entailed the stirring of a mixture of MnS QDs and PNVC in chloroform (CHCl3) at room temperature and the second method was the refluxing of MnS QDs and PNVC solution in CHCl3 at an elevated temperature. A field emission electron microscope (FESEM) study revealed that the dispersion of MnS QDs in a PNVC matrix was improved in the case of nanocomposites prepared by the second method. The optical properties of pure PNVC were significantly altered for the case of nanocomposite prepared by the second route.

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