Cadmium Phosphide Research Articles

Powder conductor for pressure calibration applied to large volume press under high pressure

Pressure is the core of high-pressure science and technology, and the accuracy of pressure calibration is of much importance for high-pressure experiments and production. Although the pressure limit of the large volume press (LVP) continues to increase, there are no well solutions for in situ pressure calibration. In this study, using in situ high-pressure electrical performance measurement technology, two ideal calibration standard materials in powder conductors, cadmium phosphide (Cd3P2) and zinc telluride (ZnTe) with stable physical and chemical properties and obvious resistance change, are applied to pressure calibration in the LVP. In situ high-pressure synchrotron radiation x-ray diffraction was used to verify the phase transition pressure point of Cd3P2. The introduction of powder conductors for pressure calibration commits to establish a pressure system, which is safer, more stable to operate, and more accurate in experimental measurements for the LVP.

Elucidating the Location of Cd2+ in Post-synthetically Treated InP Quantum Dots Using Dynamic Nuclear Polarization 31P and 113Cd Solid-State NMR Spectroscopy

Indium phosphide quantum dots (InP QD) are a promising alternative to traditional QD materials that contain toxic heavy elements such as lead and cadmium. However, InP QD obtained from colloidal synthesis are often plagued by poor photoluminescence quantum yields (PL-QYs). In order to improve the PL-QY of InP QD, a number of post-synthetic treatments have been devised. Recently, it has been shown that InP post-synthetically treated with Lewis acid metal divalent cations (M-InP) exhibit enhanced PL-QY; however, the molecular structure and mechanism behind the improved PL-QY are not fully understood. To determine the surface structure of M-InP QD, dynamic nuclear polarization surface-enhanced nuclear magnetic resonance spectroscopy (DNP SENS) experiments were employed on a series of InP magic size clusters treated with Cd ions, InP QD, cadmium phosphide (Cd₃P₂) QD, and Cd-treated InP QD (Cd–InP QD). With the use of DNP SENS, we were able to obtain the 1D ³¹P and ¹¹³Cd NMR spectra, ¹¹³Cd{³¹P} rotational-echo double-resonance (REDOR) NMR spectra, and ³¹P{¹¹³Cd} dipolar heteronuclear multiple quantum correlation (D-HMQC) sequence. Changes in the phosphide ³¹P chemical shifts after Cd treatment provide indirect evidence that some Cd alloys into the sub-surface regions of the particle. DNP-enhanced ¹¹³Cd solid-state NMR spectra suggest that most Cd ions are coordinated by oxygen atoms from either carboxylate ligands or surface phosphate groups. ¹¹³Cd{³¹P} REDOR and ³¹P{¹¹³Cd} D-HMQC experiments confirm that a subset of Cd ions are located on the surface of Cd–InP QD and coordinated with phosphate groups.

The deposition of cadmium selenide and cadmium phosphide thin films from cadmium thioselenoimidodiphosphinate by AACVD and the formation of an aromatic species.

Aerosol-assisted chemical vapour deposition (AACVD) of Cd[(SPiPr2)(SePiPr2)N]2 yields hexagonal cadmium selenide and monoclinic cadmium phosphide films on glass substrates between 475 and 525 °C at different argon flow rates. The films were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), energy dispersive analysis of X-rays (EDAX) and X-ray photoelectron spectroscopy (XPS). All the results of XRD, EDAX and XPS are in agreement with our previous investigations on Cd[(SePiPr2)2N]2. A breakdown mechanism is proposed based on mass spectra and density functional theory calculations. A large peak at m/z 207 in the mass spectra, previously assigned by us as a new aromatic species, is also observed for this complex.

P-type doping efficiency in CdTe: Influence of second phase formation.

Cadmium telluride (CdTe) high purity, bulk, crystal ingots doped with phosphorus were grown by the vertical Bridgman melt growth technique to understand and improve dopant solubility and activation. Large net carrier densities have been reproducibly obtained from as-grown ingots, indicating successful incorporation of dopants into the lattice. However, net carrier density values are orders of magnitude lower than the solubility of P in CdTe as reported in literature, 1018/cm3 to 1019/cm3 [J. H. Greenberg, J. Cryst. Growth 161, 1-11 (1996) and R. B. Hall and H. H. Woodbury, J. Appl. Phys. 39(12), 5361-5365 (1968)], despite comparable starting charge dopant densities. Growth conditions, such as melt stoichiometry and post growth cooling, are shown to have significant impacts on dopant solubility. This study demonstrates that a significant portion of the dopant becomes incorporated into second phase defects as compounds of cadmium and phosphorous, such as cadmium phosphide, which inhibits dopant incorporation into the lattice and limits maximum attainable net carrier density in bulk crystals. Here, we present an extensive study on the characteristics of these second phase defects in relation to their composition and formation kinetics while providing a pathway to minimize their formation and enhance solubility.

Synthesis of Monodisperse Cadmium Phosphide Nanoparticles Using ex-Situ Produced Phosphine

The synthesis of nanoparticles using a gas-liquid interfacial reaction, which for the first time is shown to result in highly monodisperse materials across a range of sizes, is presented. We demonstrate, using cadmium phosphide as the paradigm that this synthesis method can provide colloidal nanocrystals or quantum dots monodisperse enough so that for the first time multiple transitions in their absorbance spectra can be observed. Clear evidence is given that the resulting cadmium material is Cd(6)P(7) and not Cd(3)P(2), and a thorough investigation into the role of temperature and growth time and their effects on the optical properties has been conducted. This strategy can be extended to synthesize other relevant members of the binary component pnictide semiconducting family, and the chemistry of the pnictide compound formation using this synthetic methodology has been explained using the redox potential of the metals. The suitability of the resulting cadmium phosphide quantum dots for applications in light-emitting diodes (LEDs) has further been demonstrated.

Cadmium phosphide, Cd7P10, prepared at high pressures

In this study, pure-phase Cd7P10 crystals are prepared by the reaction of elements at high pressures in a large-volume cubic press. The synthetic Cd7P10 samples are characterized by powder X-ray diffraction, scanning electron microscopy and diamond indentation method. The results show that orthorhombic Cd7P10 grains with a size of over 70 μm could be obtained and that the high pressure well-sintered Cd7P10 compacts have a Vickers hardness value of 8.9 GPa under a load of 49 N. The pressure–temperature formation region of Cd7P10 is determined up to 5 GPa and 1500°C, and the formative mechanism under high pressures is discussed. Our results exhibit a novel route for synthesizing bulk semiconductor polystalline Cd7P10 compacts.

Cadmium Sulfide and Cadmium Phosphide Thin Films from a Single Cadmium Compound

Aerosol-assisted chemical vapor deposition of Cd[(SP(i)Pr(2))(2)N](2) leads to the growth of cadmium sulfide and/or phosphide thin films on glass. Decomposition of the precursor has been studied by pyrolysis-gas chromatography/mass spectrometry and modeled by density functional theory.

Synthesis and Characterization of Cadmium Phosphide Quantum Dots Emitting in the Visible Red to Near-Infrared

The synthesis of high-quality cadmium phosphide quantum dots with emission wavelength maxima in the range from 1200 to approximately 760 nm are reported. The results demonstrate that the nucleation and growth linked with the optical properties can be controlled by the temperature, the growth time, and the addition of ligands such as oleylamine and trioctylphosphine. Photoelectrochemical investigations revealed that the cadmium phosphide QD-derivatized electrodes show an optical response and that photocurrents of several nanoamperes per square centimeter can be obtained upon illumination.

Synthesis and band-gap photoluminescence from cadmium phosphide nano-particles

Cadmium phosphide (Cd 3P 2) when synthesized from the direct reaction of cadmium metal salt and tri-octylphosphine (TOP) in presence of sodium metal showed band-gap emissions with engineered band-gap energy in between 2.85 and 2.75 eV. Optical studies showed pronounced quantum confinement effect from nano-particles so prepared. X-ray diffraction (XRD) pattern of black powders revealed hexagonal Cd 2P 3 crystal structure. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) showed mixed morphology of fluffy particles likely to be amorphous in nature. Far-infrared (far-IR) spectroscopy revealed peaks associated with (Cd 3P 2).

Cadmium phosphide as a new material for infrared converters

Cadmium phosphide as a new material for infrared converters

Synthesis, Crystal and Electronic Structure of Cd2PCl2: Influence of Cation on Characteristic Structural Features of Pnictide Halides of Group 12 Metals.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Synthesis, crystal and electronic structure of Cd2PCl2: influence of cation on characteristic structural features of pnictide halides of Group 12 metals

Cadmium phosphide chloride Cd2PCl2 was prepared by the ampule synthesis method at 770 K. Crystals were obtained from the gaseous phase by the chemical transport reaction. The crystal structure of Cd2PCl2 is built of the P2Cd6 octahedra, which are linked in layers by sharing four equatorial vertices. The layers alternate in a fashion analogous to that observed in the K2NiF4 structural type and are linked in a three-dimensional framework through the halogen atoms. The characteristic features of the crystal and electronic structures of pnictide halides M2PCl2 (M = Cd or Hg) were considered based on X-ray diffraction data and results of quantum-chemical calculations.

A Novel Synthesis of Cadmium Phosphide Nanoparticles Using the Single-Source Precursor [MeCdPtBu2

A single-source precursor route to Cd3P2 nanoparticles is reported. Their synthesis via the thermolysis of [MeCdPtBu2]3—itself obtained using an improved procedure—in tri-n-octylphosphine oxide (TOPO) is described. The resulting TOPO-capped cadmium phosphide quantum dots are characterized by a combination of UV-vis and fluorescence emission spectroscopies, high resolution transmission electron microscopy, and elemental analysis. The effect of preparing samples with injection temperatures above 100°C is also investigated.

Characterization of two forms of cadmium phosphide by magic-angle spinning 31P NMR

Annealing of commercial grade cadmium phosphide (Cd 3P 2) at 600 K produces a material which, in magic-angle spinning spin-lattice 31P NMR relaxation experiments, has broad lines and multiple T 1 values. By contrast, sublimation at 900 K results in a crystalline material with narrow lines and a single T 1 ver, both materials have the same Cd-P lattice spacings as determined by rotational-echo, double-resonance 31P NMR with 113Cd dephasing. Both materials also have closely similar X-ray diffraction powder patterns. These results are interpreted in terms of a distribution of lattice vacancies in the annealed material, creating structural heterogeneity but with no substantial change in lattice parameters from those of the sublimed cadmium phosphide.

Sol-gel-like route to crystalline cadmium phosphide nanoclusters

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSol-gel-like route to crystalline cadmium phosphide nanoclustersMichael A. Matchett, Ann M. Viano, Natalie L. Adolphi, R. Dean Stoddard, William E. Buhro, Mark S. Conradi, and Patrick C. GibbonsCite this: Chem. Mater. 1992, 4, 3, 508–511Publication Date (Print):May 1, 1992Publication History Published online1 May 2002Published inissue 1 May 1992https://doi.org/10.1021/cm00021a007RIGHTS & PERMISSIONSArticle Views230Altmetric-Citations31LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (2 MB) Get e-AlertsSupporting Info (1)»Supporting Information Supporting Information Get e-Alerts

Growth of cadmium phosphide films by hot wall epitaxy

The Hot Wall Epitaxy (HWE) technique has been employed for the first time to grow thin epitaxial films of cadmium phosphide (Cd3P2) on mica substrates at different substrate temperatures in the range 150 – 300°C. The films were characterised by X-ray diffraction and SEM. The lattice constants calculated from the Bragg reflection are in close agreement with those reported in ASTM data. The grain size of the films is observed to increase from 1 – 2 μm as the substrate temperature is increased from 150°C to 300°C. The resistivity of the as-grown sample is around 10 Ohm cm. Thermal probe method has indicated the films to be n-type. Optical absorption measurements yielded a bandgap value of 0.58 eV.

Stimulated Emission Spectra and Valence Band Structure in the Cd3(AsxP1−x)2 System

AbstractRecombination radiation in Cd3(AsxP1−x)2 solid solutions near cadmium phosphide (x ⪅ 0.1) is studied. A complex structure of the stimulated emission spectra in Cd3(AsxP1−x)2 single crystals is detected. It is shown that for Cd3P2 the width of emission spectrum and its position relative to the transmission edge may be adequately described in terms of a direct interband‐transition model. The same model is used to calculate the luminescence Icv1(ω) and the optical transmission Tcv1(ω) in the presence of a small (i.e. up to 5% of the Brillouin zone size) K1 shift between the extrema of the heavy hole valence band V1 and conduction band C. It is shown that at k1 ≠ 0 the dependence Icv1(ω) may have two maxima. The structure of stimulated emission spectra and the reference data on luminescence in Cd3(AsxP1−x)2 single crystals are interpreted taking into account the calculations carried out in this work.

Preparation and characterisation of Cd3P2, a II–V group compound semiconductor

Cadmium phosphide (α-Cd3P2) a II3–V2 compound semiconductor has been prepared by C/H2 reduction of cadmium phosphate. The reduction process is conducted at 550°C allowing the reaction to continue for 4 to 5 hr. The material always gets deposited on the walls of the quartz tube at different zones, which after analysis is found to contain, depending upon the location of the zone, Cd3P2, CdP2 and other cadmium rich phosphides. The resistivity of the pressed samples are of the order of 3 × 10−4Θ-cm. Optical absorption spectra of thin films, obtained by thermal evaporation on glass substrates, have exhibited broad bands around 620 nm.

Analysis of the ESR spectrum of manganese(II) impurity centers in the layered compound cadmium phosphide sulfide (CdPS3)

Analysis of the ESR spectrum of manganese(II) impurity centers in the layered compound cadmium phosphide sulfide (CdPS3)

ChemInform Abstract: ELECTRONIC SPECTROSCOPY OF NEARLY OCTAHEDRALLY COORDINATED MANGANESE IN MANGANESE PHOSPHIDE SULFIDE (MNPS3) AND CADMIUM PHOSPHIDE SULFIDE (CDPS3) LATTICES

Chemischer InformationsdienstVolume 12, Issue 47 Physical Inorganic Chemistry ChemInform Abstract: ELECTRONIC SPECTROSCOPY OF NEARLY OCTAHEDRALLY COORDINATED MANGANESE IN MANGANESE PHOSPHIDE SULFIDE (MNPS3) AND CADMIUM PHOSPHIDE SULFIDE (CDPS3) LATTICES J. BOERIO-GOATES, J. BOERIO-GOATESSearch for more papers by this authorE. LIFSHITZ, E. LIFSHITZSearch for more papers by this authorA. H. FRANCIS, A. H. FRANCISSearch for more papers by this author J. BOERIO-GOATES, J. BOERIO-GOATESSearch for more papers by this authorE. LIFSHITZ, E. LIFSHITZSearch for more papers by this authorA. H. FRANCIS, A. H. FRANCISSearch for more papers by this author First published: November 24, 1981 https://doi.org/10.1002/chin.198147011AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume12, Issue47November 24, 1981 RelatedInformation