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A new process to synthesize polycrystalline samples of Sr_(14)Cu_(24)O_(41)was presented.Firstly,dry gel powder of Sr_(14)Cu_(24)O_(41)was synthesized by the citrates sol-gel method,using Sr(NO_3)_2,Cu(NO_3)_2,ethylene glycol and citrate acid as raw materials.Then,polycrystalline samples of Sr_(14)Cu_(24)O_4 l were prepared by solid- state reaction.Thermal Gravimetric and Differential Thermal Analysis(TG-DTA)showed that the temperature for solid-state reaction is at 942℃.The samples are identified to be single phase by X-ray Diffraction(XRD) and Scanning Electron Microscopy(SEM).The SEM pictures showed that the first-step particles were at even size of about 100 nm by this technique.The electronic transport measurements showed that the doping compound were semiconductor with a crossover temperature T_p in the Arrhenius plot of the resistivity versus temprature.
A new process to synthesize polycrystalline samples of Sr_ (14) Cu_ (24) O_ (41) was presented. Firstly, dry gel powder of Sr_ (14) Cu_ (24) O_ (41) was synthesized by the citrates sol-gel method , using Sr (NO_3) _2, Cu (NO_3) _2, ethylene glycol and citrate acid as raw materials.Then, polycrystalline samples of Sr_ (14) Cu_ (24) O_4 l were prepared by solid-state reaction.Thermal Gravimetric and Differential Thermal Analysis (TG-DTA) showed that the temperature for solid-state reaction is at 942 ° C. The samples are identified to be single phase by X-ray Diffraction (XRD) and Scanning Electron Microscopy the first-step particles were at even size of about 100 nm by this technique. The electronic transport measurements showed that the doping compound were semiconductor with a crossover temperature T_p in the Arrhenius plot of the resistivity versus temperature.