CdS:Mn/ZnS核壳结构纳米晶体的场致发光性质

锰掺杂的核壳结构CdS:Mn/ZnS纳米晶体由胶体化学方法制备,并将该纳米晶体所形成的薄膜夹在两层Ta₂O₅薄膜中间,形成交流薄膜电致发光器件.该器件的电致发光强度随着环境温度的升高呈现先增强后减小的变化规律,并且Mn杂质的位置会影响其电致发光谱.     

meso-四(4-磺苯基)卟啉对铕(Ⅲ)与羧酸络合物电还原的催化作用

水溶液中Eu³⁺与meso-四(4-磺苯基)卟啉(TPPS)不易形成卟啉络合物,但在乙酸、酒石酸、丙二酸等共存时,在循环伏安图上可得一对Eu³⁺还原-氧化的可逆或准可逆峰,此峰与Eu³⁺在NaClO₄底液中的还原峰相比,峰电位正移,峰电流增高。从6种Eu³⁺-羧酸络合物与TPPS共存时的实验中证明这些络合物并没有和TPPS形成三元络合物,而是吸附在汞电极上的TPPS产生电催化作用。     

钴(II)-丁二酮肟体系极谱催化波的机理研究

本文研究了钴(II)-丁二酮肟(DMG)在氨性底液(pH9)中极谱催化波的机理.用线性扫描伏安法,循环伏安法和阳极溶出法等方法证明,这催化波的形成是由于吸附在汞电极上的钴(II)-丁二酮肟螯合物不可逆地还原到零价的"活性钴",同时在电极表面的"活性钴"又催化了丁二酮肟的还原.     

稀土元素的电分析化学研究 VIII.钆与邻苯二酚紫的配合吸附波

In certain supporting electrolytes, pyrocatechol violet (PV) may be reduced at single-sweep polarograph and a well-defined wave can be observed. The height of this wave decreases when Gd3+ is added into the solution and a sharp-peaked new wave is observed at more negative potentials. The height of this new wave is proportional to the concentration of gadolinium added. NH4Cl-(CH2)6N4 mixture (pH 5.5) was chosen as the suitable supporting electrolyte, in which the new wave of the Gd3+-PV complex is higher and the difference of peak potentials between PV and complex is larger. The linear relationship between wave height and concentration of Gd3+ holds in the range of 1X10-6-2X10-5 M. In this system other rare earth elements exhibit similar wave peaks. This wave has been proved to be an adsorptive-complex wave by several experiments.     

稀土元素的电分析化学研究 X:钆-茜素红的极谱配合吸附波的研究

In a supporting electrolyte containing 2X10-4M Alizarin Red S, 0.1M NH3-NH4Cl and at pH 9.6, we obtained an adsorptive complex wave of gadolinium-Alizarin Bed S by single-sweep polarography. The peak potential of the derivative wave is -0.69V (S. C. E.). The limit of detection for gadolinium is 6X10-8M. We have determined the composition of the complex which is 1:3 GD-Alizarin Red S and confirmed that the wave is an adsorptive complex wave. The electrode processes may be presented as follows: Gd3+ + 3HL2- + 3NH3 = (GdL3)6- + 3(NH4)^+ (Chemical reaction) (GdL3)6- = (GdL3)ad6- (Surface process) The total electrochemical reaction is (GdL3)ad6- + 6e + 6(NH4)^+ = (Gd(LH2)3)ad6- + 6NH3     

稀土元素的电分析化学研究(Ⅵ)——钐-罗丹明B-氯化铵体系的极谱研究

在单扫示波极谱仪上,罗丹明B在氯化铵底液中(0.4M)的导数波(-1.45V,SCE)是一个吸附波,加入Sm³⁺能降低它的波高,二苯胍(1×10^-4M)的存在使罗丹明B(8.4×10^-5M)的波形稳定,Sm³⁺浓度为3×10^-7-2×10^-3M时,浓度与波峰的降低呈线性关系。在直流极谱仪上,在有二氧六圜存在的氯化铵底液中,钐(Ⅲ)-罗丹明B络合物在-1.7V(SCE)有一个吸附还原波。在最佳条件下(0.1M氯化铵,4.2×10^-5M罗丹明B和10%二氧六圜,pH=5.0),在浓度为2×10^-5-2×10^-5M范围内,波高与Sm³⁺浓度有正比关系。比较了稀土-罗丹明B在二氧六圜中的极谱波,销比钐灵敏,铒最灵敏;但是罗丹明B的吸附波妨碍了在它后面的络合物波的灵敏度进一步提高。     

稀土元素的电分析化学研究(Ⅰ)——铕的极谱研究

用交流极谱法比较了Eu⁺³离子在NH₄SCN、EDTA-NaCl、DTPA-NaCl三种底液中的极谱行为,其中以在DTPA-NaCl底液中的极谱可逆性为最好。使用DTPA-NaCl底液测定Eu⁺³的最宜条件为:pH>6.5,NaCl浓度>0.3M,DTPA浓度略大于溶液中全部可与DTPA络合的金属离子的总浓度。在此条件下,用交流极谱或单扫示波极谱法测定Eu⁺³的下限为2×10^-6M,用微分脉冲极谱法测定为2×10^-7M。其他稀土离子不干扰。还测定了某些稀土氧化物样品中少量的Eu,得到满意的结果。