Niobium(V) ethoxide(Nb(OEt)5) was synthesized by electrochemical reaction of ethanol with niobium plate as the sacrificial anode,stainless steel as the cathode and tetraethylammonium chloride(TEAC) as the conductive a...Niobium(V) ethoxide(Nb(OEt)5) was synthesized by electrochemical reaction of ethanol with niobium plate as the sacrificial anode,stainless steel as the cathode and tetraethylammonium chloride(TEAC) as the conductive additive.The condensates were isolated by vacuum distillation under 5 kPa.The product was characterized by Fourier transform infrared(FT-IR) spectra,Raman spectra and nuclear magnetic resonance(NMR) spectra.The results indicate that the product is niobium ethoxide.Thermal properties of niobium ethoxide were analysed by TG/DTG.Vapour pressure was calculated from the Langmuir equation and the enthalpy of vaporization was calculated from the vapour pressure-temperature data using the Clausius-Clapeyron equation.The concentrations of impurity metallic elements in the sample were detected by ICP-MS.It is shown that the purity can reach 99.997%.The volatility and purity of the niobium ethoxide ensure that it could be a good precursor for chemical vapor deposition and atomic layer deposition of niobium oxide layers.展开更多
Polystyrene doped with yttrium ethoxide was prepared. The coordination between yttrium atom and benzene ring in the polystyrene doped with yttrium ethoxide was confirmed by means of IR, XPS.
Hafnium ethoxide was synthesized using electrochemical method.Optimization experiments were used to optimizevarious parameters namely Et4NBr concentration(c):0.01?0.06mol/L,solution temperature(t):30?78°C,polar d...Hafnium ethoxide was synthesized using electrochemical method.Optimization experiments were used to optimizevarious parameters namely Et4NBr concentration(c):0.01?0.06mol/L,solution temperature(t):30?78°C,polar distance(D):2.0?4.0cm and current density(J):100?400A/m2.The electrolytic products obtained under optimum conditions of c=0.04mol/L,t=78°C,D=2.0cm and J=100A/m2were further isolated by vacuum distillation under5kPa.The product was characterized byFourier transform infrared(FT-IR)spectra,nuclear magnetic resonance(NMR)spectra.The results indicated that the product washafnium ethoxide.ICP analysis suggested that the content of hafnium ethoxide in the final product exceeded99.997%.Thermalproperties of the product were analyzed by TG/DTG.The vaporization enthalpy of hafnium ethoxide was found to be79.1kJ/mol.The result confirmed that hafnium ethoxide was suitable for the preparation of hafnium oxide by atomic layer deposition.展开更多
The formation of ( t BuCp) 2ErOEt was discussed. Its single crystal structure was determined by X ray diffraction. The crystal is monoclinic, P 2(1)/ c space group, a =1.0191(2), b =1.6203(5), c ...The formation of ( t BuCp) 2ErOEt was discussed. Its single crystal structure was determined by X ray diffraction. The crystal is monoclinic, P 2(1)/ c space group, a =1.0191(2), b =1.6203(5), c =1.2118(3) nm, β =102.960(10)°, V =1.9500 (nm 3), Z =2, D c=1.566 mg·m -3 , R =0.0450, R w=0.1363. The complex is monomeric and solvent free in the solid state. The erbium ion is coordinated by two tert butyl cyclopentadienyl rings and one oxygen atom of ethoxy group to form a seven coordinated complex.展开更多
In this work,we used the in ert substances silic one oil a nd n-hexane to modulate the solve nt environ ment,and in so doing tailor the preparation of magnesium ethoxide(Mg(0Et)2)particles.We found the following:(1)no...In this work,we used the in ert substances silic one oil a nd n-hexane to modulate the solve nt environ ment,and in so doing tailor the preparation of magnesium ethoxide(Mg(0Et)2)particles.We found the following:(1)non polar n-hexane mainly modulates the polarity of the solvent to control the precipitation rate and size of the Mg(OEt)2 seeds,thereby triggering accelerated nucleation to form small primary particles;and(2)silicone oil(relatively high polarity and viscosity)facilitates the growth and agglomeration stage,to improve inter-particle dispersion and obtain relatively uniform Mg(OEt)2 particles.We summarized these findings in a comm on mechanism for preparing Mg(OEt)2 particles with uniform morphology,small size,and high bulk density as per the synergistic effect of n-hexane and silicone oil.The ratios of silicone oil end n-hexane are flexible,and afford various regular and well-dispersed Mg(OEt)2 particles that are 5-30μm in size and 0.2-0.7 g/cm^3 in bulk density.The nanoparticles thus have the potential to serve in diverse applications such as catalysis.展开更多
基金Project(2007AA03Z425) supported by the National Hi-tech Research and Development Program of ChinaProject(50404011) supported by the National Natural Science Foundation of China
文摘Niobium(V) ethoxide(Nb(OEt)5) was synthesized by electrochemical reaction of ethanol with niobium plate as the sacrificial anode,stainless steel as the cathode and tetraethylammonium chloride(TEAC) as the conductive additive.The condensates were isolated by vacuum distillation under 5 kPa.The product was characterized by Fourier transform infrared(FT-IR) spectra,Raman spectra and nuclear magnetic resonance(NMR) spectra.The results indicate that the product is niobium ethoxide.Thermal properties of niobium ethoxide were analysed by TG/DTG.Vapour pressure was calculated from the Langmuir equation and the enthalpy of vaporization was calculated from the vapour pressure-temperature data using the Clausius-Clapeyron equation.The concentrations of impurity metallic elements in the sample were detected by ICP-MS.It is shown that the purity can reach 99.997%.The volatility and purity of the niobium ethoxide ensure that it could be a good precursor for chemical vapor deposition and atomic layer deposition of niobium oxide layers.
文摘Polystyrene doped with yttrium ethoxide was prepared. The coordination between yttrium atom and benzene ring in the polystyrene doped with yttrium ethoxide was confirmed by means of IR, XPS.
基金Project(51374254) supported by the National Natural Science Foundation of China
文摘Hafnium ethoxide was synthesized using electrochemical method.Optimization experiments were used to optimizevarious parameters namely Et4NBr concentration(c):0.01?0.06mol/L,solution temperature(t):30?78°C,polar distance(D):2.0?4.0cm and current density(J):100?400A/m2.The electrolytic products obtained under optimum conditions of c=0.04mol/L,t=78°C,D=2.0cm and J=100A/m2were further isolated by vacuum distillation under5kPa.The product was characterized byFourier transform infrared(FT-IR)spectra,nuclear magnetic resonance(NMR)spectra.The results indicated that the product washafnium ethoxide.ICP analysis suggested that the content of hafnium ethoxide in the final product exceeded99.997%.Thermalproperties of the product were analyzed by TG/DTG.The vaporization enthalpy of hafnium ethoxide was found to be79.1kJ/mol.The result confirmed that hafnium ethoxide was suitable for the preparation of hafnium oxide by atomic layer deposition.
文摘The formation of ( t BuCp) 2ErOEt was discussed. Its single crystal structure was determined by X ray diffraction. The crystal is monoclinic, P 2(1)/ c space group, a =1.0191(2), b =1.6203(5), c =1.2118(3) nm, β =102.960(10)°, V =1.9500 (nm 3), Z =2, D c=1.566 mg·m -3 , R =0.0450, R w=0.1363. The complex is monomeric and solvent free in the solid state. The erbium ion is coordinated by two tert butyl cyclopentadienyl rings and one oxygen atom of ethoxy group to form a seven coordinated complex.
基金the National Natural Science Foundation of China(grant numbers 21422603,U1662120,and 21978152).
文摘In this work,we used the in ert substances silic one oil a nd n-hexane to modulate the solve nt environ ment,and in so doing tailor the preparation of magnesium ethoxide(Mg(0Et)2)particles.We found the following:(1)non polar n-hexane mainly modulates the polarity of the solvent to control the precipitation rate and size of the Mg(OEt)2 seeds,thereby triggering accelerated nucleation to form small primary particles;and(2)silicone oil(relatively high polarity and viscosity)facilitates the growth and agglomeration stage,to improve inter-particle dispersion and obtain relatively uniform Mg(OEt)2 particles.We summarized these findings in a comm on mechanism for preparing Mg(OEt)2 particles with uniform morphology,small size,and high bulk density as per the synergistic effect of n-hexane and silicone oil.The ratios of silicone oil end n-hexane are flexible,and afford various regular and well-dispersed Mg(OEt)2 particles that are 5-30μm in size and 0.2-0.7 g/cm^3 in bulk density.The nanoparticles thus have the potential to serve in diverse applications such as catalysis.
