In this work, with the purpose to explore the coordination chemistry of calcium complexes which could work as a partial model of manganese-calcium cluster, a spectrophotometric study to evaluate the stability of the c...In this work, with the purpose to explore the coordination chemistry of calcium complexes which could work as a partial model of manganese-calcium cluster, a spectrophotometric study to evaluate the stability of the complexes: Calcium(Ⅱ)-1,2-ethylendiamine, Calcium(Ⅱ)-1,3-propanediamine and Calcium(Ⅱ)-1,4-butanediamine in acetonitrile, were carried on. By processing the spectrophotometric data with the HypSpec program allows the determination of the formation constants. The logarithmic values of the formation constants obtained for Calcium(Ⅱ)-1,2-ethylendiamine, Calcium(Ⅱ)-1,3-propanediamine and Calcium(Ⅱ)-1,4-butanediamine were log β_(110) = 4.69, log β_(110)= 5.25 and log β_(110) = 4.072, respectively.展开更多
Co（Ⅱ）-salen was encapsulated in MIL- 100（Cr） metal organic framework by ＂ship in a bottle＂ to synthesize a new electrocatalyst, Cosalen@MIL- 100（Cr）. The material was characterized by XRD, FT-IR, UV-Vis and N...Co（Ⅱ）-salen was encapsulated in MIL- 100（Cr） metal organic framework by ＂ship in a bottle＂ to synthesize a new electrocatalyst, Cosalen@MIL- 100（Cr）. The material was characterized by XRD, FT-IR, UV-Vis and N2-adsorption. The Cosalen@MIL-100（Cr） modified glassy carbon electrode exhibits a well-defined reduction peak at the potential of -0.21 V toward the oxygen reduction reaction （ORR） by cyclic voltam- metry （CV） in pH = 6.84 phosphate buffer. Almost 400 mV positive shift of potential at Cosalen@MIL-100（Cr） modified electrode for ORR compared with that at bare glassy carbon, indicates that Cosalen@MIL-100（Cr） possesses excellent electrocatalytic activity. The transferred number of electrons for ORR was determined by chronocoulometry. The result suggests that the introduction of Co（II）-salen complex into MOF increases the electrocatalytic activity via a four-electron reduction pathway. Furthermore, this electrocatalyst exhibits good stability and reproducibility.展开更多
基金the Secretaria de Educacion Publica(SEP)through PRODEP program for their economic support in the project "Equilibrios de Formacion de Complejos de Manganeso(Ⅱ)-Diamina para su Aplicacion en Sistemas de Fotosintesis Artificial"the Secretaria de Innovacion,Cienciay Educacion Superior(SICES)for its economic support through their program"Convocatoria de Investigadores Jovenes 2016",in the project "Obtencion de Clusteres Manganeso-Calcio para su Aplicacion Potencial en Sistemas de Fotosintesis Artificial"
文摘In this work, with the purpose to explore the coordination chemistry of calcium complexes which could work as a partial model of manganese-calcium cluster, a spectrophotometric study to evaluate the stability of the complexes: Calcium(Ⅱ)-1,2-ethylendiamine, Calcium(Ⅱ)-1,3-propanediamine and Calcium(Ⅱ)-1,4-butanediamine in acetonitrile, were carried on. By processing the spectrophotometric data with the HypSpec program allows the determination of the formation constants. The logarithmic values of the formation constants obtained for Calcium(Ⅱ)-1,2-ethylendiamine, Calcium(Ⅱ)-1,3-propanediamine and Calcium(Ⅱ)-1,4-butanediamine were log β_(110) = 4.69, log β_(110)= 5.25 and log β_(110) = 4.072, respectively.
基金supported by the Program for New Century Excellent Talents in University(NCET-04-0270)the National Basic Research Program of China(2011CB201301)
文摘Co（Ⅱ）-salen was encapsulated in MIL- 100（Cr） metal organic framework by ＂ship in a bottle＂ to synthesize a new electrocatalyst, Cosalen@MIL- 100（Cr）. The material was characterized by XRD, FT-IR, UV-Vis and N2-adsorption. The Cosalen@MIL-100（Cr） modified glassy carbon electrode exhibits a well-defined reduction peak at the potential of -0.21 V toward the oxygen reduction reaction （ORR） by cyclic voltam- metry （CV） in pH = 6.84 phosphate buffer. Almost 400 mV positive shift of potential at Cosalen@MIL-100（Cr） modified electrode for ORR compared with that at bare glassy carbon, indicates that Cosalen@MIL-100（Cr） possesses excellent electrocatalytic activity. The transferred number of electrons for ORR was determined by chronocoulometry. The result suggests that the introduction of Co（II）-salen complex into MOF increases the electrocatalytic activity via a four-electron reduction pathway. Furthermore, this electrocatalyst exhibits good stability and reproducibility.
