To improve the electrochemical properties of rare-earth-Mg-Ni-based hydrogen storage alloys, the effects of stoichiometry and Cu-substitution on the phase structure and thermodynamic properties of the alloys were stud...To improve the electrochemical properties of rare-earth-Mg-Ni-based hydrogen storage alloys, the effects of stoichiometry and Cu-substitution on the phase structure and thermodynamic properties of the alloys were studied. Nonsubstituted Ml0.80Mg0.20（Ni2.90Co0.50-Mn0.30Al0.30）x （x=0.68, 0.70, 0.72, 0.74, 0.76） alloys and Cu-substituted Ml0.80Mg0.20（Ni2.90Co0.50-yCuyMn0.30Al0.30）0.70 （y=0, 0.10, 0.30, 0.50） alloys were prepared by induction melting. Phase structure analysis shows that the nonsubstituted alloys consist of a LaNi5 phase, a LaNi3 phase, and a minor La2Ni7 phase;in addition, in the case of Cu-substitution, the Nd2Ni7 phase appears and the LaNi3 phase vanishes. Ther-modynamic tests show that the enthalpy change in the dehydriding process decreases, indicating that hydride stability decreases with in-creasing stoichiometry and increasing Cu content. The maximum discharge capacity, kinetic properties, and cycling stability of the alloy electrodes all increase and then decrease with increasing stoichiometry or increasing Cu content. Furthermore, Cu substitution for Co ame-liorates the discharge capacity, kinetics, and cycling stability of the alloy electrodes.展开更多
A series of 3-pyridinyl-6-aryl-l, 2, 4-triazolo[3, 4-b][1, 3, 4]thiadiazoles(PATT) were prepared, the structures were confirmed by IR and H NMR spectra. The results of cyclic 1 voltammetry measurements imply that all ...A series of 3-pyridinyl-6-aryl-l, 2, 4-triazolo[3, 4-b][1, 3, 4]thiadiazoles(PATT) were prepared, the structures were confirmed by IR and H NMR spectra. The results of cyclic 1 voltammetry measurements imply that all these compounds have a higher electron affinity (EA) than 2-(4-biphenyl)-5-(4-tert-butyl phenyl)-1, 3, 4-oxadiazole (PBD) which implies that PATT could be acting as better electron acceptors than widely used electron transporting material PBD.展开更多
Two binuclear copper（Ⅱ） complexes, [Cu2（saloph）2 （μ-O）2]·2（DMF）[Hasaloph N,N＇-o-phenylenebis（salicylideneaminato）] （a） and [Cu2（salen）2（μ-O）2] [H2salen=N,N＇-bis（salicylic-deneaminato） ethyl...Two binuclear copper（Ⅱ） complexes, [Cu2（saloph）2 （μ-O）2]·2（DMF）[Hasaloph N,N＇-o-phenylenebis（salicylideneaminato）] （a） and [Cu2（salen）2（μ-O）2] [H2salen=N,N＇-bis（salicylic-deneaminato） ethylene] （b）were synthesized and characterized by X-ray crystal-lography. Both of them have distorted rectangular pyramidal geometry around Cu（Ⅱ）. The complete series of complexes show bridging phenoxo groups between the copper centers, together with hydroxo-bridges in these complexes. The complexes have also been characterized by elemental analysis, IR, TG-DTA, and electrochemical results.展开更多
基金supported by the National Natural Science Foundation of China(Nos.21303157 and 21106123)the Natural Science Foundation of Hebei Province,China(No.B2012203104)+1 种基金the China Postdoctoral Science Foundation Project(2013M541201)the Research Fund for the Doctoral Program of Higher Education of China(20131333120008)
文摘To improve the electrochemical properties of rare-earth-Mg-Ni-based hydrogen storage alloys, the effects of stoichiometry and Cu-substitution on the phase structure and thermodynamic properties of the alloys were studied. Nonsubstituted Ml0.80Mg0.20（Ni2.90Co0.50-Mn0.30Al0.30）x （x=0.68, 0.70, 0.72, 0.74, 0.76） alloys and Cu-substituted Ml0.80Mg0.20（Ni2.90Co0.50-yCuyMn0.30Al0.30）0.70 （y=0, 0.10, 0.30, 0.50） alloys were prepared by induction melting. Phase structure analysis shows that the nonsubstituted alloys consist of a LaNi5 phase, a LaNi3 phase, and a minor La2Ni7 phase;in addition, in the case of Cu-substitution, the Nd2Ni7 phase appears and the LaNi3 phase vanishes. Ther-modynamic tests show that the enthalpy change in the dehydriding process decreases, indicating that hydride stability decreases with in-creasing stoichiometry and increasing Cu content. The maximum discharge capacity, kinetic properties, and cycling stability of the alloy electrodes all increase and then decrease with increasing stoichiometry or increasing Cu content. Furthermore, Cu substitution for Co ame-liorates the discharge capacity, kinetics, and cycling stability of the alloy electrodes.
文摘A series of 3-pyridinyl-6-aryl-l, 2, 4-triazolo[3, 4-b][1, 3, 4]thiadiazoles(PATT) were prepared, the structures were confirmed by IR and H NMR spectra. The results of cyclic 1 voltammetry measurements imply that all these compounds have a higher electron affinity (EA) than 2-(4-biphenyl)-5-(4-tert-butyl phenyl)-1, 3, 4-oxadiazole (PBD) which implies that PATT could be acting as better electron acceptors than widely used electron transporting material PBD.
基金Supported by the Project for Distinguished Young Scholars from Hubei Provincial Department of Education (Q20082601)
文摘Two binuclear copper（Ⅱ） complexes, [Cu2（saloph）2 （μ-O）2]·2（DMF）[Hasaloph N,N＇-o-phenylenebis（salicylideneaminato）] （a） and [Cu2（salen）2（μ-O）2] [H2salen=N,N＇-bis（salicylic-deneaminato） ethylene] （b）were synthesized and characterized by X-ray crystal-lography. Both of them have distorted rectangular pyramidal geometry around Cu（Ⅱ）. The complete series of complexes show bridging phenoxo groups between the copper centers, together with hydroxo-bridges in these complexes. The complexes have also been characterized by elemental analysis, IR, TG-DTA, and electrochemical results.
