锂硼钨酸盐玻璃的分相及其对电性质的影响

Phase Separation in Lithium Borotungstate Glasses and Its Effect on the Electrical Properties

In this work,the phase separation in glasses in the Li_2O-B_2O_3-WO_3 system andits effects on electrical properties of glasses are studied.It is found that there is awide liquid-in-liquid phase separation region and exsists second phase separationphenomenon in this system.In phase-separated glasses,the matrix phase is rich inboron oxide and the droplet phase is rich in tungsten oxide.The microcrystallitesare observed to be deposited along the spherical surface of the droplet phase,indica-ting that the phase separation in glasses promotes crystallization.As a result of thephase separation,the ionic conductivity of the ion conductive glasses in the basicarea of the glass-forming region increases and that of the mixed conductive glassesin the acidic area decreases but their electronic conductivity increases,and the diele-ctric constant of the glasses increases,however,the electrode capacitance of the sa-mples at low frequences greatly decreases because of the increased electronic conduc-tivity.