Preparation Of Metal Chain Complex And Graphene Compound Electrode

Novel hybrid molecules containing metal atom chains have attracted more and more attention due to their special optical, electrical, magnetic and catalytic properties. Herein, we synthesized Ni3(dpa)4-(2-THc)2 through the condensation reaction between Ni3(dpa)4Cl2(dpa=2,2’-dipyridylamine anion) and 2-THc Ag(2-THc Ag=2-thiophenecarboxylate silver) by the elimination of Ag Cl. This indirectly proved that hybrid chain polymer poly[Ni3(dpa)4-(2,5-THdc)] can also be synthesized uising Ni3(dpa)4Cl2 and 2,5-THdc Ag2(2,5-THdc Ag2=2,5-thiophenedicarboxylate silver) through this method. Due to the reversible redox property and good conductivity of Ni3(dpa)4Cl2, we link Ni3(dpa)4Cl2 with reduced graphite(r GO) by chemical bond to synthesize r GO-C≡C-Ni3(dpa)4(Me CN)(PF6)(donated as r GO-C≡C-Ni3). FTIR, Mass spectrometry(MS), X-Ray diffraction(XRD), X-ray photoelectron spectroscopy(XPS) and 1H NMR analysis suggested that we synthesized above substances successfully.XPS analysis of poly[Ni3(dpa)4-(2,5-THdc)] confirm that the state of Ni remains to be Ni(II), the same as Ni3(dpa)4Cl2. Through the measurement of XPS, Energy dispersive spectrometer(EDS) and TG, We estimat that there is approximately 1 Ni3(dpa)42+ metal chain unit for every 300~400 carbons in r GO-C≡C-Ni3. Compared with Ni3(dpa)4Cl2, poly[Ni3(dpa)4-(2,5-THdc)] possesses stronger fluorescence emission intensity with absolute fluorescence quantum efficiency as high as 6.7%, and its fluorescence lifetime up to 1.54 μs. By contrast with [Ni3(dpa)4(Me CN)2](PF6)2, r GO-C≡C-Ni3 shows significant increase of fluorescence emission intensity due to its more efficient conjugation with both ?-delocalization and ?-conjugation. Magnetization analysis indicats that poly[Ni3(dpa)4-(2,5-THdc)] has stronger magnetic susceptibility than Ni3(dpa)4Cl2 and shows unsaturation even at an applied magnetic field of 5 T. RGO-C≡C-Ni3 exhibits paramagnetism but weaker than Ni3(dpa)4Cl2. Electrochemical measurement suggest that poly[Ni3(dpa)4-(2,5-THdc)] shows an irreversible oxidation process with an onset oxidation of-0.26 V and posseses a band gaps of 1.34 e V which confirms that poly[Ni3(dpa)4-(2,5-THdc)] can be easier stimulated than Ni3(dpa)4Cl2. Though RGO-C≡C-Ni3 exhibits lower specific capacitance, power density than r GO/[Ni3(dpa)4(Me CN)2](PF6)2 in 1.0 M Na2SO4 aqueous electrolyte, RGO-C≡C-Ni3 shows better electrochemical cycling stability. RGO-C≡C-Ni3 indicats higher specific capacitance, energy density and power density in 6.0 M KOH aqueous electrolyte than in 1.0 M Na2SO4 aqueous electrolyte, but similar electrochemical cycling stability in those two electrolyte.