高热稳定性低电阻率钴钡掺杂氧化锰薄膜电极材料制备

Preparation of High Thermostability and Low Resistivity(Co,Ba)-Doped MnO_2 Electrodes

通过化学溶液共沉积结合旋涂技术,制备了钴(Co)钡(Ba)掺杂的二氧化锰(MnO_2)薄膜电极材料,在微晶玻璃电容器接近击穿时断路,从而起到保护电路的作用。对材料进行表征的结果表明,此种方法制备的Co、Ba掺杂的MnO_2其热稳定温度达到850℃,高于纯MnO_2薄膜电极的600℃。材料的电阻率下降,在Co含量为8mol%时,材料的电阻率达到0.207Ω·cm,接近纯MnO_2的电阻率。MnO_2电极在玻璃基片上附着性良好且厚度均匀。材料的高热稳定性和低电阻率可提高其应用效率。

MnO_2 thin films doped with Ba and Co were prepared by codeposition and spin-coating. We used a graceful failure mechanism of MnO_2 electrode which can convert to the insulator Mn_2O_3 phase for high-temperature capacitors, and which comprised high-energy density glass or glass–ceramic dielectrics and MnO_2 thin-film electrodes. The property of the MnO_2 electrode was studied by the four-point collinear probe meter, XRD, DSC, SEM, and SEM-EDS. The results indicate that the α-MnO_2 structure is stabilized by Ba insertion into an oxygen tunnel frame to form a hollandite structure, which could lead to the stable α-MnO_2 phase at 850 oC. The Co doping can reduce the quantity of Mn^(3+) convent from Mn^(4+) in the process of calcining. When the doped amount of Co is 8 mol%, the resistivity reaches the 0.207 ?·cm, which is close to the resistivity of pure MnO_2. The MnO_2 electrode adheres on the glass substrate closely, and the thinness of electrode is uniform. The Ba, Co doped MnO_2 is expected to be useful in self-healing cathode with graceful failure mode and other high-temperature sensor applications.