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Correction for ‘Controlled synthesis of pentachlorophenol-imprinted polymers on the surface of magnetic graphene oxide for highly selective adsorption’ by Sheng-Dong Pan et al., J. Mater. Chem. A, 2014, 2, 15345–15356.

A series of mercapto-functionalized core–shell structured nano-magnetic Fe 3 O 4 polymers (SH-Fe 3 O 4 -NMPs) with different amount of magnetic core were synthesized and characterized by XRD, EA, VSM, TG–DTG and XPS. Their applications as adsorbents for Hg(II) removal from aqueous solutions were intensively investigated. The adsorption process of Hg(II) by SH-Fe 3 O 4 -NMPs was found highly pH dependent and related to the content of Fe 3 O 4 magnetic core in the adsorbents. The optimized content of magnetic core for SH-Fe 3 O 4 -NMPs was found to be at 5.88%. Kinetic studies showed that the adsorption of Hg(II) by SH-Fe 3 O 4 -NMPs followed pseudo-second-order model, suggesting a chemisorption process. Activation energy ( E a ) for the Hg(II) removal was found to be 22.1 kJ mol −1 , indicating that the diffusion process might be the rate-controlled step. Thermodynamic studies suggested that the adsorption processes of Hg(II) onto the SH-Fe 3 O 4 -NMPs were endothermic and entropy favored in nature with the enthalpy changes (Δ H θ ) at 7.26–16.54 kJ mol −1 and the entropy changes (Δ S θ ) at 27.60–56.78 J mol −1 K −1 . The adsorption processes fit the Langmuir isotherms well with the maximum adsorption capacities of Hg(II) onto the SH-Fe 3 O 4 -NMPs at 129.9–256.4 mg g −1 with the content of Fe 3 O 4 in SH-Fe 3 O 4 -NMPs varying from 0% to 22.37%. The selective adsorption of Hg(II) by SH-Fe 3 O 4 -NMPs can be achieved when Ca 2+ , Mg 2+ , Na + or Cu 2+ ions coexisted. XRD and XPS analyses results of the adsorbents before and after Hg(II) adsorption suggested that Hg(II) ions had been successfully adsorbed onto SH-Fe 3 O 4 -NMPs via coordination interactions, and Hg(II) might be partially reduced to Hg 2 Cl 2 through solid state redox reaction via charge transport on the surface of the SH-Fe 3 O 4 -NMPs, in which the Fe 3 O 4 magnetic core in the adsorbents might play an important role.

A series of NH 2 -functionalized nano-magnetic polymer adsorbents (NH 2 -NMPs) coupled with different multi-amino groups, i.e ., ethylenediamine (EDA), diethylenetriamine (DETA), triethylenetetramine (TETA) and tetraethylenepentamine (TEPA), named as EDA-NMPs, DETA-NMPs, TETA-NMPs and TEPA-NMPs have been prepared and used for the investigation of the adsorption mechanism of Cu(II) and Cr(VI) co-existing water system. Three approaches, e.g. by adsorbing Cu(II), Cr(VI) from water simultaneously, or adsorbing Cr(VI) followed by adsorbing Cu(II), and vice versa , were applied for the adsorption mechanism investigation. The results showed that the adsorption of Cu(II) or/and Cr(VI) on NH 2 -NMPs was competitive as well as cooperative. The adsorption mechanisms of Cu(II), Cr(VI) co-existing system could be related with coordination interactions, electrostatic attraction, and ion exchange. New adsorbents can be obtained via adsorption of Cu(II) or Cr(VI) by NH 2 -NMPs, named as Cu-NH 2 -NMPs, i.e. , Cu-EDA-NMPs, Cu-DETA-NMPs, Cu-TETA-NMPs, Cu-TEPA-NMPs; and Cr-NH 2 -NMPs, i.e. , Cr-EDA-NMPs, Cr-DETA-NMPs, Cr-TETA-NMPs, Cr-TEPA-NMPs, respectively. Cu-NH 2 -NMPs and Cr-NH 2 -NMPs can be reused for the adsorption of Cr(VI) or Cu(II), with high selectivity, broad pH applicable range and comparable adsorption properties with NH 2 -NMPs themselves.

In this study, a novel NH2-functionalized nano-sized magnetic polymer (TEPA-NMP) adsorbent coupling with tetraethylenepentamine (TEPA) had been prepared. Its application for the removal of Cr(VI) from industrial wastewater was investigated. Batch adsorption studies were carried out to evaluate the effects of pH value, initial concentration, adsorption isotherm, adsorption kinetics, and desorption characters etc. The adsorption of Cr(VI) reached equilibrium rapidly within 30 mins. The adsorption efficiency of the TEPA-NMP on Cr(VI) was dependent on pH value and the initial Cr(VI) concentration. The adsorption efficiency of Cr(VI) decreased with the increasing of the initial Cr(VI) concentration and pH value. The adsorption data were well fitted with the Langmuir isotherm. The maximum adsorption capacity calculated from the Langmuir isotherm was 370.4 mg/g at temperature of 35 °C and pH of 2.0. Regeneration studies indicated that the adsorbent could be reused for 8 times with only 3.4 % lost of adsorption efficiency. The adsorption mechanism study results suggested that the adsorption of Cr(VI) could be related with electrostatic attraction, ion exchange and coordination interactions.

The selective oxidation of alcohols with molecular oxygen was efficiently completed in high conversion and selectivity using HPW/MCM-41 as a heterogeneous photocatalyst in ionic liquids, [bmim]PF6, [omim]BF4 and [hmim]BF4. Comparative studies on the catalytic properties of HPW/MCM-41, HPW to MCM-41 were carried out. Some important variables, e.g. the loading amount of HPW on MCM-41 and the effects of different ionic liquids were discussed in this work.

The selective oxidation of alcohols with molecular oxygen was efficiently completed in high conversion and selectivity using copper-bisisoquinoline-based catalysts under mild reaction condition. The effects of various parameters such as reaction temperature, reaction time, oxidant, ligands, etc, were studied. Solvent effect has been as well studied in ionic liquids [bmim]PF6, [omim]BF4 and [hmim]BF4, comparing to traditional volatile organic solvent. The use of ionic liquids was found to enhance the catalytic properties of the catalysts used.

Four new tetranuclear complexes, [Cu(en)2]3Ru(ox)3Cl3 (1), [Ni(en)2]3Ru(ox)3Cl3 (2), [Cu(bpy)2]3Ru(ox)3Cl3 (3) and [Ni(bpy)2]3Ru(ox)3Cl3 (4), have been prepared and characterized by elemental analyses, infrared and electronic spectra. The copper(II) complexes have been further characterized by ESR. The cyclic voltammograms of the four complexes have been studied. Magnetic investigation of (1) shows that this compound presents an antiferromagnetic interaction (J=−5.73 cm−1) between oxalate-bridged Cu(II)-Ru(III) units.

Two new Schiff base ligands (3-MeSGH and 4-MeSGH) derived from methyl-substituted salicylaldehyde (MeS) and D-glucosamine (GA), and ten of their metal complexes ML2 (M= Cu(II), Zn(II), Fe(II), Co(II), Ni(II); HL=3-MeSGH or 4-MeSGH) were prepared and characterized by elemental analyses, infrared and electronic spectra, molar conductivity measurements and magnetic moments at room temperature. The Schiff base ligands and the zinc(II) complexes were further characterized by 1H and 13C NMR. The copper(II) complexes were also characterized by ESR. All the complexes are non-electroly tes and superoxide free radical scavengers.

Cu(II), Zn(II), Fe(III), Co(III), and Ni(II) complexes of D-glucosamine (GluH2·HCl) were synthesized. These complexes, Cu (II)(GluH)(OAc)(H2O)·H2O (1), Zn(II)(GluH)(OAc)(H2O)·H2O (2), Fe(III)(Glu)(OAc)(H2O)·H2O (3), Co(III)(Glu)(OAc)(H2O)·H2O (4), and Ni(II)(GluH)(OAc)(H2O)·H2O (5), were characterized by elemental analyses, conductivity and magnetic susceptibility measurements, and infrared and electronic spectra. Cu(II)(GluH)(OAc)(H2O)·H2O was further characterized by ESR. The ligand (GluH2·HCl) and Zn(II) (GluH)(OAc)(H2O)·H2O were also characterized by 1H NMR and 13C NMR. It is suggested that all of the complexes have pseudo-tetrahedral structures and are nonelectrolytes. These complexes are superoxide free radical (O2 −·) scavengers.

Four novel binuclear Ln(III) complexes containing the dianion of phthalic acid (phth) as a bridging ligand have been synthesized, namely [Ln2(phth)(phen)4](CIO4)4.xH2O and [Ln2(phth)(NO2-phen)4](CIO4)4.xH2O (Ln = Dy, Nd; phth = dianion of phthalic acid; phen = 1,10-phenanthroline; NO2-phen = 5-nitro-1,10-phenanthroline). The complexes have been characterized by elemental analyses, IR, electronic spectra and conductances. The variable-temperature magnetic susceptibility (4-300K) of the complex [Dy2(phth)(NO5-phen)4](CIO4)4.6H2O has been determined, and the data were fit to the susceptibility equation derived from the spin Hamilton, Ĥ=δ[Lcirc]z 2+gβH·Ĵi+2Z′J′+MJ(Ĵz), by the least square method. The exchange interaction parameters are Z′J′ = -5. 94 × 10−4 cm−1 indicating that there is a weak antiferromagnetic spin exchange interaction between the lanthanide ions in the complex.

A hydrogen-bonded complex Ru(bpy)2(OX)·4H2O has been synthesized. Its structure consists of a unique three-dimensional network in which Ru(bpy)2(OX)·4H2O units are alternatively linked by tetracyclic and octacyclic rings. The cyclic voltammogram of the titled compound has been studied.

Cu(II), Fe(II), Co(II), Ni(II), Mn(II) complexes of azido-l, 4-bis(imidazol-l-yl-methyl)benzene (bix) or 1, 4-bis(imidazol-l-yl-methyl)-2.5-dimethyl-benzene) (Mebix) were synthesized by the spontaneous self-assembly method. The compounds [Cu2(bix)3(N3)4-2H2O. Ni2(bix)3(N3)46H2O. Co2(bix)3(N3)4·6H2O, Cu2(Mebix)3(N3)4·4H2O, Mn2(Mebix)3(N3)4·6H2O, Ni2(Mebix)3(N3)4·4H2O] were characterized by element analyses, infrared and electronic spectra. Cu2(bix)3(N3)4·2H2O was further characterized by ESR. It is suggested that all the complexes have ID structures, in which bix or Mebix functions as bridging ligand and N3' as terminal ligand. The coordination environment is distorted octahedral for each metal ion.

Cu(II), Zn(II), Fe(II), Fe(III), Co(II), Co(III). Ni(II) complexes with the Schiff basc derived from D-glucosamine and 2-hydroxynaphthaldehyde (NGH2) were synthesized. These compounds [Cu(II)NG 2H2O, Zn(II)(NGH)2. H2O, Fe(II)NG .2H2O, Fe(III)NG(OAc) .H2O, Co(II)NG .2H2O, Co(III)NG(OAc).H2O and Ni(II)(NGH)2 .4H2O] were characterized by element analyses, conductivity measurements, infrared and electronic spectra. The Schiff base ligand (NGH2) and Zn(II)(NGH)2. H2O were further characterized by 1H NMR and 13C NMR. Cu(II)NG 2H2O was also characterized by ESR. It is suggested that all the complexes have pseudo-tetrahedral structures. All the complexes are non-electrolytes. These complexes are superoxide free radical (O2) scavengers.

A one-dimensional 4,4′-bipy-bridged compound [Mn(hfac)2(4,4′-bipy)]n (hfac = hexafluoroacetetylacetonato; 4,4′-bipy = 4,4′-bipyridine) has been prepared and its structure has been determined. The structure consists of a zigzag-one-dimensional chain in which Mn(II) ion is bridged by 4,4′-bipy. The coordination environment is distorted octahedral for Mn(II), and Mn(hfac)2(4,4′-bipy) has a cis coordination. Magnetic investigation shows that this compound presents a very weak antiferromagnetic interaction (J = −0.196 cm−1, gMn, = 2.02, F = 2.24 × 10−3).

In this work, four novel tetraethylenepentamine (TEPA)-functionalized nano-sized magnetic polymers (TEPA NMPs) adsorbents have been applied for the removal of Cu(II) from wastewater. Batch adsorption studies were carried out to evaluate the effects of pH value, initial concentration, adsorption isotherm, and adsorption kinetics etc. The adsorption of Cu(II) reached equilibrium rapidly within 90 mins. The adsorption efficiency of the TEPA-NMPs on Cu(II) was dependent on pH value, the initial Cu(II) concentration and the amount of the crosslink agent, i.e., divinylbenzen (DVB) used for the prepreation of the adsorbents. The adsorption efficiency of Cu(II) decreased with the increasing of the initial Cu(II) concentration and pH value. The adsorption data were well fitted with the Langmuir isotherm. The maximum adsorption capacity calculated from the Langmuir isotherm was 116.28 mg·g-1 at temperature of 308 K and pH of 4.0. Thermodynamic parameters like ΔHθ, ΔSθ and ΔGθ for the adsorption of Cu(II) onto the TEPA-NMPs have been estimated, which suggested that the adsorption processes of Cu(II) onto the TEPA-NMPs were endothermic and entropy favored in nature, with ΔH at 15.42 kJ·mol-1, ΔS at 62.54 J·mol-1·K-1.

A new five-coordinate nickel(II) complex of a trans[14]diene macrocyclic ligand has been prepared and characterized by X-ray crystallography, u.v. and i.r. spectroscopy. The coordination environment of the nickel(II) ion is a distorted square pyramid with the nickel(II) ion deviating from the level plane 0.25 A and the SCN ligand at the apical side.

The preparation, X-ray crystal structure, and magnetic properties of a novel three-dimensional oxalate-bridged heterometal supramolecular complex {K[Cu(trans[14]dien)]Cr(ox)3}n (trans[14]dien = 5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradeca-4,11-diene; ox = oxalate ion) have been reported. The magnetic investigation showed that the oxalate-bridged chromium(III)−copper(II) units were antiferromagnetically coupled (J = −9.88 cm-1).