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1.
The complexes of 4-chloro-2-methoxybenzoic acid anion with Mn2+,
Co2+, Ni2+, Cu2+
and Zn2+ were obtained as polycrystalline solids
with general formula M(C8H6ClO3)2·nH2O and colours typical for M(II) ions (Mn – slightly pink, Co –
pink, Ni – slightly green, Cu – turquoise and Zn – white).
The results of elemental, thermal and spectral analyses suggest that compounds
of Mn(II), Cu(II) and Zn(II) are tetrahydrates whereas those of Co(II) and
Ni(II) are pentahydrates. The carboxylate groups in these complexes are monodentate.
The hydrates of 4-chloro-2-methoxybenzoates of Mn(II), Co(II), Ni(II), Cu(II)
and Zn(II) heated in air to 1273 K are dehydrated in one step in the range
of 323–411 K and form anhydrous salts which next in the range of 433–1212
K are decomposed to the following oxides: Mn3O4,
CoO, NiO and ZnO. The final products of decomposition of Cu(II) complex are
CuO and Cu. The solubility value in water at 293 K for all complexes is in
the order of 10–3 mol dm–3.
The plots of χM
vs.
temperature of 4-chloro-2-methoxybenzoates of Mn(II), Co(II), Ni(II) and Cu(II)
follow the Curie–Weiss law. The magnetic moment values of Mn2+,
Co2+, Ni2+ and Cu2+
ions in these complexes were determined in the range of 76−303 K and
they change from: 5.88–6.04 μB for Mn(C8H6ClO3)2·4H2O, 3.96–4.75
μB for Co(C8H6ClO3)2·5H2O, 2.32–3.02 μB for Ni(C8H6ClO3)2·5H2O and 1.77–1.94
μB for Cu(C8H6ClO3)2·4H2O. 相似文献
2.
The reaction of [M(L)]Cl2 · 2H2O (M = Ni2+ and Cu2+, L = 3,14-dimethyl-2,6,13,17-tetraazatricyclo[14,4,01.18,07.12]docosane) with 1,1-cyclobutanedicarboxylic acid (H2-cbdc) generates 1D and 2D hydrogen-bonded infinite chains [Ni(L)(H-cbdc−)2] (1) and [Cu(L)(H-cbdc−)2] (2). (H-cbdc− = cyclobutane-1-carboxylic acid-1-carboxylate). These complexes have been characterized by X-ray crystallography, spectroscopy,
and cyclic voltammetry. The crystal structure of 1 shows a distorted octahedral coordination geometry around the nickel(II) ion, with four secondary amines and two oxygen atoms
of the H-cbdc− ligand at the trans position. In 2, the coordination environment around the central copper(II) ion shows a Jahn–Teller distorted octahedron with four Cu–N bonds
and two long Cu–O distances. The cyclic voltammogram of the complexes undergoes two one-electron waves corresponding to MII/MIII and MII/MI processes. The electronic spectra and electrochemical behavior of the complexes are significantly affected by the nature
of the axial H-cbdc− ligand. 相似文献
3.
L. N. Mazalov S. V. Trubina I. M. Oglezneva N. A. Kryuchkova O. V. Tarasenko V. L. Varand T. E. Kokina S. V. Larionov 《Journal of Structural Chemistry》2005,46(3):542-545
X-ray photoelectron and voltammetry studies of the charged state of the metal atom in nickel(II) chelate complexes with ligands
containing CS
2
−
and PS
2
−
groups and in heteroligand complexes on their basis were carried out. It is shown that the degree of formal oxidation of
the nickel atom in the complexes corresponds to Ni(II). In the case of heteroligand complexes, addition of nitrogen heterocycles
causes an increase in the electron density on the atoms of the coordination center. Theoretical data obtained in ab initio quantum chemical model calculations correlate with the experimental results.
Original Russian Text Copyright ? 2005 by L. N. Mazalov, S. V. Trubina, I. M. Oglezneva, N. A. Kryuchkova, O. V. Tarasenko,
V. L. Varand, T. E. Kokina, and S. V. Larionov
__________
Translated from Zhurnal Strukturnoi Khimii, Vol. 46, No. 3, pp. 554–557, May–June, 2005. 相似文献
4.
Wiesława Ferenc Beata Bocian J. Sarzyński 《Journal of Thermal Analysis and Calorimetry》2006,84(2):377-383
Four new complexes of 2,3,4-trimethoxybenzoic acid
anion with manganese(II), cobalt(II), nickel(II) and copper(II) cations were
synthesized, analysed and characterized by standard chemical and physical
methods. 2,3,4-Trimethoxybenzoates of Mn(II), Co(II), Ni(II) and Cu(II) are
polycrystalline compounds with colours typical for M(II) ions. The carboxylate
group in the anhydrous complexes of Mn(II), Co(II) and Ni(II) is monodentate
and in that of Cu(II) monohydrate is bidentate bridging one. The anhydrous
complexes of Mn(II), Co(II) and Ni(II) heated in air to 1273 K are stable
up to 505–517 K. Next in the range of 505–1205 K they decompose
to the following oxides: Mn3O4,
CoO, NiO. The complex of Cu(II) is stable up to 390 K, and next in the range
of 390–443 K it loses one molecule of water. The final product of its
decomposition is CuO. The solubility in water at 293 K is of the order of
10–3 mol dm–3
for the Mn(II) complex and 10–4 mol dm–3
for Co(II), Ni(II) and Cu(II) complexes. The magnetic moment values of Mn2+,
Co2+, Ni2+ and Cu2+
ions in 2,3,4-trimethoxybenzoates experimentally determined in the range of
77–300 K change from 5.64–6.57 μB (for Mn2+),
4.73–5.17 μB (for Co2+), 3.26–3.35 μB
(for Ni2+) and 0.27–1.42 μB (for Cu2+).
2,3,4-Trimethoxybenzoates of Mn(II), Co(II) and Ni(II) follow the Curie–Weiss
law, whereas that of Cu(II) forms a dimer. 相似文献
5.
The new Co(II), Cu(II), Ni(II) and Zn(II) complexes of potentially N2O2 Schiff base ligand [N,N’-bis(salicyldehydene)-1,4-bis-(o-aminophenoxy)butane] (H2L) prepared from 1,4-bis-(o-aminophenoxy)butane and salicyldehyde in DMF. Microanalytical data, elemental analysis, magnetic measurements, lH NMR, 13C NMR, UV-visible and IR spectra as well as conductance measurements were used to confirm the structures. In all complexes,
H2L behaves as a tetradentate.
The article is published in the original. 相似文献
6.
A new series of binuclear unsymmetrical compartmental oxime complexes (1–5) [M2L] [M=Cu(II), Ni(II)] have been synthesized using mononuclear complex [ML] (L=1,4-bis[2-hydroxy-3-(formyl)-5-methylbenzyl]piperazine), hydroxylamine hydrochloride and triethylamine. In this system there are two different compartments, one has piperazinyl nitrogens and phenolic oxygens and the other compartment has two oxime nitrogens and phenolic oxygens as coordinating sites. The complexes were characterized by elemental and spectral analysis. Electrochemical studies of the complexes show two step single electron quasi-reversible redox processes at cathodic potential region. For copper complexes E1 pc=−0.18 to −0.62 and E2 pc=−1.18 to −1.25 V, for nickel complexes E1 pc=−0.40 to −0.63 and E2 pc=−1.08 to −1.10 V and reduction potentials are sensitive towards the chemical environment around the copper and nickel atoms. The nickel(II) complexes undergo two electrons oxidation. The first one electron oxidation is observed around +0.75 V and the second around +1.13 V. ESR Spectra of the binuclear copper(II) complexes [Cu2L](ClO4), [Cu2L(Cl)], [Cu2L(NO3)] shows a broad signal at g=2.1 indicating the presence of coupling between the two copper centers. Copper(II) complexes show a magnetic moment value of μeff around 1.59 B.M at 298 K and variable temperature magnetic measurements show a −2J value of 172 cm−1 indicating presence of antiferromagnetic exchange interaction between copper(II) centres. 相似文献
7.
Wiesława Ferenc Agnieszka Walków-Dziewulska Maria Wojciechowska J. Sarzyński 《Journal of Thermal Analysis and Calorimetry》2006,86(2):359-364
Physico-chemical properties of 4-chloro-2-nitrobenzoates of Co(II),
Ni(II), and Cu(II) were studied. The complexes were obtained as mono- and
trihydrates with a metal ion to ligand ratio of 1:2. All analysed 4-chloro-2-nitrobenzoates
are polycrystalline compounds with colours depending on the central ions:
pink for Co(II), green for Ni(II), and blue for Cu(II) complexes. Their thermal
decomposition was studied only in the range of 293–523 K, because it
was found that on heating in air above 523 K 4-chloro-2-nitrobenzoates decompose
explosively. Hydrated complexes lose crystallization water molecules in one
step and anhydrous compounds are formed. The final products of their decomposition
are the oxides of the respective transition metals. From the results it appears
that during dehydration process no transformation of nitro group to nitrite
takes place. The solubilities of analysed complexes in water at 293 K are
of the order of 10–4–10–2
mol dm–3. The magnetic moment values of Co2+,
Ni2+ and Cu2+ ions in
4-chloro-2-nitrobenzoates experimentally determined at 76–303 K change
from 3.89 to 4.82 μB for Co(II) complex, from 2.25
to 2.98 μB for Ni(II) 4-chloro-2-nitrobenzoate,
and from 0.27 to 1.44 μB for Cu(II) complex. 4-chloro-2-nitrobenzoates
of Co(II), and Ni(II) follow the Curie–Weiss law. Complex of Cu(II)
forms dimer. 相似文献
8.
Melchor González-Dávila J. Magdalena Santana-Casiano Frank J. Millero 《Journal of solution chemistry》2006,35(1):95-111
The oxidation rates of nanomolar levels of Fe(II) in seawater (salinity S = 36.2) by mixtures of O2 and H2O2 has been measured as a function of pH (5.8–8.4) and temperature (3–35∘C). A competition exists for the oxidation of Fe(II)
in the presence of both O2 (μ mol⋅L−1 levels) and H2O2 (nmol⋅L−1 levels). A kinetic model has been applied to explain the experimental results that considers the interactions of Fe(II) with
the major ions in seawater. In the presence of both oxidants, the hydrolyzed Fe(II) species dominate the Fe(II) oxidation
process between pH 6 and 8.5. Over pH range 6.2–7.9, the FeOH+ species are the most active, whereas above pH 7.9, the Fe(OH)02 species are the most active at the levels of CO2−3 concentration present in seawater. The predicted Fe(II) oxidation rate at [Fe(II)]0 = 30nmol⋅L−1 and pH = 8.17 in the oxygen-saturated seawater with [H2O2]0 = 50nmol⋅L−1 (log 10 k = −2.24s−1) is in excellent agreement with the experimental value of log 10 k = −2.29s−1 ([H2O2]0 = 55nmol⋅L−1, pH = 8). 相似文献
9.
The interaction between nickel and pectin extracted from citrus fruit was studied in 0.10 M KNO3, at pH 5.5 and 25 °C. Differential pulse and/or square wave polarography were used to determine free nickel. For a high coverage degree (θ) of the pectin by the metal ion a good fitting was observed between experimental results and the model that includes both complex species, ML and ML2 (M for the metal ion and L for the ligand). In the ML2 species, Ni(II) interacts with two carboxylate groups of different chains, resulting in an inter-chain association. For low θ values, the formation of ML2 is hindered due to the repulsion between the negative charges of carboxylic groups in two independent segments of pectin. The influence of calcium or copper ions on the free nickel concentration, in the presence of pectin, may lead to a decrease in free nickel concentration, contrary to what would be expected from direct competition between Ca(II) or Cu(II) and Ni(II) for the pectin binding sites. This is due to the partial neutralisation of the negative carboxylic charges by the positive charges of the divalent cations, which favours NiL2 formation through the association of independent chains. 相似文献
10.
Processes of electrochemical oxidation of Pd-rich Pd–Ni alloys in basic solutions were studied with the aim of electrochemical
quartz crystal microbalance. Potentials of current peaks of Ni(II)/Ni(III) redox couple are independent of alloy composition.
On the other hand, Ni(II)/Ni(III) redox couples formed on Pd–Ni alloys and Ni differ in respect to the structure of involved
compounds and the processes of transport of the species accompanying oxidation/reduction reaction. The process of oxidation
of Pd exhibits some differences between pure Pd and Pd–Ni alloys. This concerns mainly on participation of adsorbed water/OH− in Pd oxidation process. In the initial stages of Pd oxidation, the source of oxygen is water/OH− from the bulk of the solution. At this stage of the process, the product of Pd oxidation could be described as Pd(OH)2 or PdOH2O. With further progress in oxidation process, adsorbed species, water/OH−, start to play a decisive role. Hydrous species, i.e. Pd(OH)2 or PdOH2O, are also reduced in the final stages of Pd(II) reduction process.
This study is dedicated to the 70th birthday of Professor Oleg Petrii. 相似文献
11.
Robert I. Haines James E. Rowley 《Journal of inclusion phenomena and macrocyclic chemistry》2003,47(1-2):25-32
Three nickel(II) pentaazamacrocycles bearing pendant alkyl tails have been synthesized,and the crystal structure of one (bearing an octyl tail) is reported. The redox potentials of the complexes, for oxidation of the nickel(II) centre, is 0.72 V (versus S.H.E.) in all cases, indicating that the pendant alkyl tails have no effect on the redox site. The kinetics of oxidation of the complexes by peroxodisulfate, S2O8 2- and by aqua(5, 5, 7,12, 12, 14-hexamethyl-1,4,8,11-tetraazacyclotetradecane-1-acetato)nickel(III),[Ni(hmca)(OH2)]2+ have been studied. Oxidation by S2O8 2- occursby ion-pairing of the reactants, followed by electron transfer with concomitant peroxo bond fissure. Oxidation by [Ni(hmca)(OH2)]2+ occurs by an outer sphere electron transfer process. Redox kinetics at the nickel centre provides a probe for supramolecular interactions at the pendant tails in such complexes. 相似文献
12.
Reduction by NaBH4 of the imine functions of (5,7,7,13-tetramethyl-13-nitro-1,4,8,11-tetraazacyclotetradec-4-ene)-nickel(II) and -copper(II), and of their 13-ethyl-5,7,7-trimethyl-homologues, yield the nitro-substituted cyclic tetraamine cations (5,5,7,13-tetramethyl-13-nitro-1,4,8,11-tetraazacyclotetradecane)-nickel(II) and -copper(II), [M(neh)]2+, and (13-ethyl-5,5,7-trimethyl-homologues, [M(nph)]2+, respectively. The nickel(II) cations form square–planar, singlet ground, state salts with poorly coordinating anions and octahedral, triplet ground state, compounds with additional ligands, trans-β-[Ni(neh)A2], A− = Cl−, NCS− and trans-β-[Ni(neh)A2](ClO4)2, X = NH3, MeCN, all with nitrogen configuration III, 1R,4R,8S,11S = β. With oxalate the chain-polymeric compound catena-trans-β-[Ni(neh)(μ-C2O4)]n · 3n(H2O) is formed. Folded macrocycle compounds cis-α-[Ni(neh)(C5H7O2)]ClO4 and cis-α-[{Ni(neh)}2(C2O4)](ClO4)2 are formed with the chelates acetylacetonate and oxalate, with configuration 1R,4R,8R,11R = α. These react with HClO4 to form metastable α-[Ni(neh)](ClO4)2 with retention of configuration. The copper(II) cations form crimson salts with poorly coordinating anions and compounds of the type β-[Cu(neh)A]ClO4 of varying shades of blue with coordinating anions. Structures of singlet ground state square–planar nickel(II) compounds β-[Ni(neh)](ClO4)2 · H2O, β-[Ni(neh)](ClO4)2, β-[Ni(neh)]2[ZnCl3(OH2)]2[ZnCl4] · H2O and α-[Ni(neh)](ClO4)2, the triplet ground state chain-polymeric compound catena-trans-β-[Ni(neh)(μ-C2O4)]n · 3n(H2O) and of square–pyramidal β-[Cu(nph)Cl]ClO4 are reported. 相似文献
13.
A new vic-dioxime ligand, N,N′-bis(aminopyreneglyoxime) (LH2), and its copper(II), nickel(II) and cobalt(II) metal complexes were synthesized and characterized by elemental analyses,
IR, UVVIS and 1H and 13C NMR spectra (for the ligand). Mononuclear complexes were synthesized by a reaction of ligand (LH2) and salts of Co(II), Ni(II), and Cu(II) in ethanol. The complexes have the metal-ligand ratio of 1: 2 and metals are coordinated
by N,N′ atoms of vicinal dioximes. The ligand acts in a polydentate fashion bending through nitrogen atoms in the presence of a base,
as do most vic-dioximes. Detection of a H-bonding in the Co(II), Ni(II), and Cu(II) complexes by IR revealed the square-planar MN4 coordination of mononuclear complexes. Fluorescent properties of the ligand and its complexes arise from pyrene units conjugated
with a vic-dioxime moiety. Fluorescence emission spectra of the ligand showed a drastic decrease in its fluorescence intensity upon
metal binding. The electrochemical properties of the complexes were studied by the cyclic voltammetry technique. The nickel
complex displayed an irreversible oxidation process while the copper complex exhibited a quasi-reversible oxidation and reduction
processes based on the copper Cu(II)/Cu(III) and Cu(II)/Cu(I) couples, respectively. 相似文献
14.
I. V. Mironov 《Russian Chemical Bulletin》1998,47(10):1864-1867
The influence of the ion background (NaClO4, LiClO4, and HClO4) on the kinetics of the reaction PtdientH2O2++X−→PtdientX++H2O(X=Cl, Br, I, SCN, and N3) was studied at 25°C by spectrophotometry. Changes in the rate constant with increase in the ionic strength are described
by the Debye-Hückel and Gosh-Bjerrum equations. The reaction PtdienCl++H2O→PtdientH2O2++Cl− was studied by potentiometry and its rate constant was established to depend weakly on variations of the medium.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1918–1921, October, 1998. 相似文献
15.
Galactose oxidase (GOase) is a fungal enzyme which is unusual among metalloenzymes in appearing to catalyse the two electron
oxidation of primary alcohols to aldehydes and H2O2. The crystal structure of the enzyme reveals that the coordination geometry of mononuclear copper(II) ion is square pyramidal,
with two histidine imidazoles, a tyrosinate, and either H2O (pH 7.0) or acetate (from buffer,pH 4-5) in the equatorial sites and a tyrosinate ligand weakly bound in the axial position. This paper summarizes the results
of our studies on the structure, spectral and redox properties of certain novel models for the active site of the inactive
form of GOase. The monophenolato Cu(II) complexes of the type [Cu(L1)X][H(L1) = 2-(bis(pyrid-2-ylmethyl)aminomethyl)-4-nitrophenol and X− = Cl−
1, NCS−
2, CH3COO−
3, ClO4
−
4] reveal a distorted square pyramidal geometry around Cu(II) with an unusual axial coordination of phenolate moiety. The coordination
geometry of 3 is reminiscent of the active site of GOase with an axial phenolate and equatorial CH3COO− ligands. All the present complexes exhibit several electronic and EPR spectral features which are also similar to the enzyme.
Further, to establish the structural and spectroscopic consequences of the coordination of two tyrosinates in GOase enzyme,
we studied the monomeric copper(II) complexes containing two phenolates and imidazole/pyridine donors as closer structural
models for GOase. N,N-dimethylethylenediamine and N,N’-dimethylethylenediamine have been used as starting materials to obtain
a variety of 2,4-disubstituted phenolate ligands. The X-ray crystal structures of the complexes [Cu(L5)(py)], (8) [H2(L5) = N,N-dimethyl-N’,N’-bis(2-hydroxy-4-nitrobenzyl) ethylenediamine, py = pyridine] and [Cu(L8)(H2O)] (11), [H2(L8) = N,N’-dimethyl-N,N’-bis(2-hydroxy-4-nitrobenzyl)ethylenediamine] reveal distorted square pyramidal geometries around Cu(II) with the axial tertiary
amine nitrogen and water coordination respectively. Interestingly, for the latter complex there are two different molecules
present in the same unit cell containing the methyl groups of the ethylenediamine fragmentcis to each other in one molecule andtrans to each other in the other. The ligand field and EPR spectra of the model complexes reveal square-based geometries even in
solution. The electrochemical and chemical means of generating novel radical species of the model complexes, analogous to
the active form of the enzyme is presently under investigation. 相似文献
16.
The tripodal ligand N,N′,N″-tri(benzimidazolyl)-methane has been used to synthesize nickel(II) complexes along with an exogeneous
ligand, X(X = Cr−,NO
3
−
,ClO
4
−
, HCOO−, OAc− and CNS−). Electronic absorption spectra reveal that the present nickel(II) complexes have six coordinate tetragonal geometries. The
value of Racah parameter(B), crystal field splitting parameter (Dq) and term,β0 (which is a measure of covalency) have been calculated.1HNMR spectroscopy reveals a dominantσ-delocalization pattern in these complexes. 相似文献
17.
《Journal of Coordination Chemistry》2012,65(15):2727-2734
Bis(N-alkyldithiocarbamato)nickel(II) complexes (1–5) [Ni(S2CNHR)2] (where R?=?Me, Et, n-Pr, i-Pr, n-Bu) were synthesized by the reaction of NiCl2?·?6H2O and the corresponding sodium salt of N-alkyldithiocarbamate in 1?:?2 molar ratio in aqueous medium. These bis(N-alkyldithiocarbamato)nickel(II) complexes (1–5) were characterized by elemental analysis, UV-Visible, IR, and 1H/13C-NMR spectroscopy. The crystallographic investigation of [Ni(S2CNH(n-Pr))2] (3) and [Ni(S2CNH(i-Pr))2] (4) revealed distorted square-planar geometry around nickel(II). The dithiocarbamates have anisobidentate coordination with nickel and the dithiocarbamates are trans. 相似文献
18.
Ion Association and Hydration in Aqueous Solutions of Nickel(II) and Cobalt(II) Sulfate 总被引:1,自引:0,他引:1
Aqueous solutions of nickel(II) and cobalt(II) sulfate have been investigated at 25 ∘C by dielectric relaxation spectroscopy (DRS) over a wide range of frequencies (0.2 ≤ ν (GHz) ≤ 89) and salt concentrations
(0.025 ≤ c(mol-L−1) ≤ 1.4). The spectra indicate, as for MgSO4(aq) studied previously, the simultaneous presence of double solvent-separated, solvent-shared and contact ion pairs in both
NiSO4(aq) and CoSO4(aq). The stepwise formation constants for each ion-pair type and the overall association constant, obtained from the data
are in good agreement with ultrasonic relaxation and other estimates. The DR spectra at higher concentrations (c ≥ 0.5 mol-L−1) suggest the existence of a nonlinear triple ion M2SO42+(aq). Consistent with the very strong hydration of the salts, which have ‘effective’ hydration numbers approaching 27 at infinite
dilution, there are no significant differences in any of the relaxation or thermodynamic parameters for NiSO4(aq) and CoSO4(aq), except that the triple ion appears to be somewhat more stable for the latter. 相似文献
19.
Guillermo González-Alatorre Andres García-Godínez Vicente Rico-Ramírez Eleazar Escamilla-Silva Enrique A. Botello 《Reaction Kinetics and Catalysis Letters》2008,94(2):337-344
The oxygenation constants and thermodynamic parameters (ΔHo, ΔSo) of a series of novel Co(II) dihydroxamic acids containing a central functional group (-OCH3) CoL1∼CoL6 were measured, their catalytic performance in the oxidation of p-xylene to p-toluic acid (PTA) were examined. The influence of` ligand structure, the substituents (X = Cl, OCH3 and Y = H, CH3, Cl) of the aromatic rings and added alkaline cations on the O2-binding capabilities and catalytic oxidation activities were investigated. 相似文献
20.
Genovaitė Valiulienė Albina Žielienė Birutė Šimkūnaitė Leonas Naruškevičius Loreta Tamašauskaitė Tamašiūnaitė Vidas Pakštas Algis Selskis 《Journal of Solid State Electrochemistry》2010,14(2):203-212
The electrochemical behavior of Bi2S3 coatings in Watts nickel plating electrolyte was investigated using the cyclic voltammetry, electrochemical quartz crystal
microbalance, X-ray diffraction, and energy dispersive X-ray analysis methods. During the bismuth sulfide coating reduction
in Watts background electrolyte in the potential region from −0.4 to −0.6 V, the Bi2S3 and Bi(III) oxygen compounds are reduced to metallic Bi, and the decrease in coating mass is related to the transfer of S2− ions from the electrode surface. When the bismuth sulfide coating is reduced in Watts nickel plating electrolyte, the observed
increase in coating mass in the potential region −0.1 to −0.4 V is conditioned by Ni2+ ions reduction before the bulk deposition of Ni, initiated by Bi2S3. In this potential region, the reduction of Bi(III) oxygen compounds can occur. After the treatment of as-deposited bismuth
sulfide coating in nickel plating electrolyte at E = −0.3 V, the sheet resistance of the layer decreases from 1013 to 500–700 Ω cm. A metal-rich mixed sulfide Ni3Bi2S2–parkerite is obtained when as-deposited bismuth sulfide coating is treated in Watts nickel plating electrolyte at a potential
close to the equilibrium potential of the Ni/Ni2+ system and then annealed at temperatures higher than 120 °C. 相似文献