钛基SnO2+SbOx电极固溶体生长活化能及作用机制

Growth Activation Energy of Ti-Based SnO2 + SbOx Electrode Solid Solution and Its Activation Mechanism

摘要:

采用热分解法制备SnO2+SbOx钛基氧化物电极，利用TG/DTA、XRD和XPS等手段对SnO2+SbOx固溶体进行表征，计算SnO2+SbOx固溶体的生长活化能，并探讨SnO2+SbOx固溶体的作用机制，同时采用快速寿命法考察氧化物电极在0.5 mol/L H2SO4溶液中2 A/cm2下的预期使用寿命。结果表明： Sb掺杂SnO2形成的N型半导体和P型半导体产生的自由电子和氧空位使得电极导电性增强，预期使用寿命增加为30 h，晶粒表面氧空位的存在和非常低的晶间旋转驱动力是导致SnO2+SbOx固溶体的生长活化能降低为12.63 kJ/mol的主要原因。因此，Sb掺杂SnO2形成的电极固溶体是一种导电性好和稳定性高的电极材料。

Abstract:

Ti based oxide anode with SnO2+SbOx was prepared by a thermal decomposition method. The SnO2+SbOx solid solution was characterized with TG/DTA, XRD and XPS. The growth activation energy of SnO2+SbOx solid solution was calculated and its activation mechanism was discussed. Meanwhile the expected lifetime of the oxide anode under high current density of 2 A/cm2 and in 0.5 mol/L H2SO4 solution was determined by a fast life method. The results show that the free electrons and oxygen vacancy produced by the N-type semiconductor and P-type semiconductor from Sb-doped SnO2 enhance the electrode conductivity and increase its expected lifetime to 30 h. The oxygen vacancy and too low intergranular rotary driving force are the main reasons for the decrease to 12.63 kJ/mol of the growth activation energy of SnO2+SbOx solid solution. Thus, SnO2+SbOx electrode solid solution is a fine electrode material with good conductivity and high stability.