• Applied Science and Convergence Technology
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• v.23 no.1
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• pp.14-26
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• 2014

Copper is an important component from coin metal to electronic wire, integrated circuit, and to lithium battery. Copper oxides, mainly including $Cu_2O$ and CuO, are important semiconductors for the wide applications in solar cell, catalysis, lithium-ion battery, and sensor. Due to their low cost, low toxicity, and easy synthesis, copper oxides have received much research interest in recent year. Herein, we review the crystallization of copper oxides by designing various chemical reaction routes, for example, the synthesis of $Cu_2O$ by reduction route, the oxidation of copper to $Cu_2O$ or CuO, the chemical transformation of $Cu_2O$ to CuO, the chemical precipitation of CuO. In the designed reaction system, ligands, pH, inorganic ions, temperature were used to control both chemical reactions and the crystallization processes, which finally determined the phases, morphologies and sizes of copper oxides. Furthermore, copper oxides with different structures as electrode materials for lithium-ion batteries were also reviewed. This review presents a simple route to study the reaction-crystallization-performance relationship of Cu-based materials, which can be extended to other inorganic oxides.

• Journal of Powder Materials
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• v.29 no.5
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• pp.370-375
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• 2022

Cu-doped ZnSe quantum dots were successfully synthesized in an aqueous solution using an internal doping method. The effects of ligand type, CuSe synthesis temperature, and heating time on Cu-doped ZnSe synthesis were systematically investigated. Of MPA, GSH, TGA, and NAC used as ligands, MPA was the optimal ligand as determined by PL spectrum analysis. In addition, the emission wavelength was found to depend on the synthesis temperature of the internal doping core of CuSe. As the temperature increased, the doping of Cu²⁺ was enhanced, and the emission wavelength band was redshifted; accordingly, the emission peaks moved from blue to green (up to 550 nm). Thus, the synthesis of Cu:ZnSe using internal doping in aqueous solutions is a potential method for ecomanufacturing of color-tuned ZnSe quantum dots for display applications.

• Bulletin of the Korean Chemical Society
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• v.34 no.11
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• pp.3233-3238
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• 2013

Two new Cu(II) complexes, $[Cu_2(acpy-mdtc)_2(HBA)(ClO_4)]{\cdot}H_2O$ (1) (acpy-mdtc- = 2-acetylpyridine S-methyldithiocarbamate and $HBA^-$ = benzilic acid anion) and $[Cu_2(acpy-phtsc)_2(HBA)]{\cdot}ClO_4$ (2) (acpy-$phtsc^-$ = 2-acetylpyridine 4-phenyl-3-thiosemicarbazate) have been synthesized and characterized by elemental analysis, infrared spectroscopy, thermogravimetric analysis, and single crystal X-ray diffraction. The X-ray analysis reveals that the structures of 1 and 2 are dinuclear copper(II) complexes bridged by two thiolate sulfur atoms of Schiff base ligand and bidentate bridging $HBA^-$ anion. For 1, each of the two copper atoms has different coordination environments. Cu1 adopts a five-coordinate square-pyramidal with a $N_2OS_2$ donor, while Cu2 exhibits a distorted octahedral geometry in a $N_2O_2S_2$ manner. For 2, two Cu(II) ions all have a five-coordinate square-pyramidal with a $N_2OS_2$ donor. In each complex, the Schiff base ligand is coordinated to copper ions as a tridentate thiol mode.

• Bulletin of the Korean Chemical Society
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• v.31 no.6
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• pp.1704-1710
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• 2010

The structure of a 2D grid-like copper(II) complex [Cu$(NCO)_2$(pyz)](pyz=pyrazine) (1) consists of 1D chains of Cu-pyz units connected by double end-on (EO) cyanato bridges. Each Cu(II) ion has a distorted octahedral coordination, completed by the four EO cyanato and two pyrazine ligands. Magnetic interactions through EO cyanato and pyrazine bridges in 1 are discussed on the basis of DFT broken-symmetry calculations at the B3LYP level. For model dicopper(II) complexes I (bridged by cyanato) and II (bridged by pyrazine), electronic structure calculations reproduce very well the experimental couplings for the S = 1/2 ferromagnetic and antiferromagnetic exchange-coupled 2D system: the calculated exchange parameters J are +1.25 $cm^{-1}$ and -3.07 $cm^{-1}$ for I and II, respectively. The $\sigma$ orbital interactions between the Cu $x^2-y^2$ magnetic orbitals and the nitrogen lone-pair orbitals of pyrazine are analyzed from the viewpoint of through-bond interaction. The energy splitting of 0.106 eV between two SOMOs indicates that the superexchange interaction should be antiferromagnetic in II. On the other hand, there are no bridging orbitals that efficiently connect the two copper(II) magnetic orbitals in I because the HOMOs of the basal-apical NCO bridge do not play a role in the formation of overlap interaction pathway. The energy separation in the pair of SOMOs of I is calculated to be very small (0.054 eV). This result is consistent with the occurrence of weakly ferromagnetic properties in I.

• Nano
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• v.13 no.10
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• pp.1850114.1-1850114.7
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• 2018

Here we report an optimized hot-injection method and a phase transfer strategy for the synthesis of water-soluble $CuInS_2$ QDs with desired properties. The structure and morphology studies demonstrate that the resulting QDs are $CuInS_2$ tetragonal phase with well-defined facets. It is also found that the crystal size gradually increases with the increase of reaction temperature, while the surface of QDs with pre- and post-phase transfer is functionalized with hydrophobic and hydrophilic ligands, respectively. Spectroscopy measurements reveal the size-dependent optical properties of $CuInS_2$ QDs, demonstrating the quantum confinement effect in this system.

• Journal of the Korean Chemical Society
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• v.29 no.6
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• pp.637-645
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• 1985

To predict speciation of copper and cadmium in natural waters, the stability constant of complexes formed between copper or cadmium and natural organic ligands have been determined by the ion selective electrodes at pH 6. The stability constants for copper and cadmium, log $K'_{CuL} = 5.80\;and\;log K'_{CdL}=3.82$, were incorporated inot MINEQL computer program and prediction of chemical species of copper and cadmium in a model fresh water system was made by using this computer program. The natural organic ligands form complex with cupric ions at the concentration of $10^{-6}$ moles/l and with cadmium ions at the concentration of $10^{-5}$ moles/l. This result showed that prediction of chemical species of heavy metals in natural waters was not possible without taking into account the presence of the natural organic ligands.

• The Korean Journal of Ecology
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• v.28 no.1
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• pp.7-13
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• 2005

In the present study, we investigated the tolerance of Commelina communis to growth in Cu-contaminated soil and water We examined the germination rate, root and shoot growth of seedlings, fresh biomass in soil and water, and ability to eliminate Cu. We found that C. communis eliminated 41% of Cu in soil containing 50 mg Cu/kg and removed over 50% of Cu from water containing 100 mg Cu/L Cu. In addition, the plants could accumulate 90 mg Cu/g when grown in soil containing 50 mg Cu/kg and 140 mg Cu/g when grown in soil containing 100 mg Cu/kg thus higher levels of Cu removal were observed in soils containing higher Cu concentrations. In water, the maximal accumulation rate was 4.9 mg Cu/g root and 1.2 mg Cu/g shoot in water containing 20 mg Cu/L, and 7 days after exposure, Cu absorption saturated. Further, the growth rate of C. communis was not affected by up to 100 mg Cu/kg in the soil. Therefore, the phytotoxic effect of Cu on plants increased as the concentration of Cu was raised, although to different extents depending on whether the Cu was in soil or water. Overall, Cu removal from soil by C. communis was most effective at 100 mg Cu/kg in soil and 10 mg Cu/L in water. Finally, we identified two peaks of Cu-binding ligands in C. communis. Which is a high molecular weight peak (HMWL) at 60 kDa (Fraction 17 to 25) and a Cu binding peptide peak at <1 kDa (Very low molecular weight ligand: VLMWL). Cu-binding peptide (Cu-BP) was observed to have an amino acid composition typical of phytochelations.

• Journal of the Korean Chemical Society
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• v.47 no.6
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• pp.569-577
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• 2003

Ligands, Br-PEMP, Cl-PEMP and $CH_3O-PEMP$ having Br, Cl and $CH_3O$ substituents at 5-position of the $N_2O$ tridentate ligand, 2-[(2-pyridine-2-ethylamio)-methyl]-phenol (H-PEMP) containing pyridine and phenol were synthesized. Another ligand, Naph-PEMP having pyridine and 2-hydroxy-1-naphthalene was also synthesized. The ligands were characterized using elemental analysis, UV-visible, IR, $^1H\;NMR\;and\;^{13}C$ NMR spectroscopy and mass analysis. The potentiometric titration study in aqueous solution revealed that the proton dissociation of the ligands occurred in three steps and the order of overall proton dissociation constants (log${\beta}$) was $CH_3O-PEMP$ > Naph-PEMP > H-PEMP > Cl-PEMP > Br-PEMP. The order of stability constants (logML and log$ML_2$) of their transition metal complexes was Co(II) < Ni(II) < Cu(II) > Zn(II). The order in their stability constants values of each transition metal complex agreed well with that in overall proton dissociation constant value of the ligands.

• Journal of the Korean Chemical Society
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• v.55 no.1
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• pp.28-37
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• 2011

Spectroscopic (infrared, electronic and $1^H$-NMR), elemental analyses CHN, molar conductivity, thermogravimetric analyses (TGA/DTG) and biological studies, of both benzanthrone derivatives 3-N-2-hydroxy ethylamine benzanthrone (HEAB) and 3-N-2-amino ethylamine benzanthrone (AEAB) with Cu(II), Co(II) and Ni(II) chlorides were discussed herein. Based on the above studies, HEAB ligand was suggested to be coordinated to each metal ions via hydroxo and amino groups to form [Cu(HEAB)$(Cl)_2$].$2H_2O$, [Co(HEAB)$(Cl)_2(H_2O)_2$].$8H_2O$ and [Ni(HEAB)$(Cl)_2(H_2O)_2$].$7H_2O$ coordinated complex. On the other hand, AEAB has an octahedral coordinated feature with formulas [Cu(AEAB)$(Cl)_2(H_2O)_2$].$2H_2O$, [Co(AEAB)$(Cl)_2(H_2O)_2$].$4H_2O$ and [Ni(AEAB)$(Cl)_2(H_2O)_2$]. $6H_2O$. The molar conductance values at $25{\circ}C$ for all complexes in DMF are slightly higher than free ligands; this supported the presence of chloride ions inside the coordination sphere. Both benzanthrone ligands and their complexes have been screened against different kinds of bacteria.

• Plant Resources
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• v.7 no.3
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• pp.163-169
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• 2004

To investigate the defense mechanism against the abiotic stress, a cDNA clone encoding a CuZn superoxide dismutase (CuZnSOD) protein was isolated from a cDNA library prepared from tabroot mRNAs of Codonopsis lanceolata. The eDNA, designated ClSODCc, is 799 nucleotides long and has an open reading frame of 459 bp with a deduced amino acid sequence of 152 residues. The deduced amino acid sequence of ClSODCc matched to the previously reported CuZnSODs. Consensus amino acid residues (His-45, -47, -62, -70, -79, -119 and Asp-82) were involved in Cu-, Cu/Zn-, and Zn- binding ligands. The deduced amino acid sequence of ClSODCc showed high homologies (82％-86％) regardless of species. Expression of ClSODCc by oxidative stress was increased up to 1 h after treatment and declined gradually. Much earlier and stronger expression of ClSODCc was observed in the cold stress treatment.