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以钛酸四丁酯、五水硝酸铋为主要原料,采用溶胶-凝胶法在ITO导电玻璃基片表面制备铋掺杂摩尔分数分别为0、2％、4％、6％、8％和10％的TiO2薄膜,采用TG-DTA、XRD、电化学工作站、紫外可见分光光度计等表征铋掺杂TiO2薄膜.循环伏安分析显示:铋掺杂后薄膜的阴极还原峰由1个增至3个且峰流值变大,其电流响应时间变化不大,未掺杂和铋掺杂TiO2薄膜的着色效率(CE)最大值分别为3.08 cm2·C-、6.17 cm2·C-1.少量铋掺杂可以使TiO2正八而体结构发生扭曲变形,提高薄膜的电致变色性能,但过多的铋离子可能会富集于基质的晶界处,增加了锂离子的迁移阻力,甚至阻隔锂离子进入TiO2层中.未掺杂和铋掺杂TiO2凝胶加热至400℃后热稳定性良好;热处理500℃时其粉末为锐钛矿,且掺杂量越高无定形程度越高.

Electrochromic TiO2 films doped with 0,2％,4％,2％,8％ and 10％ (mole fraction) bismuth were prepared on the ITO glass surface by the sol-gel method using Ti(OC4H9)4 and Ri (NO3)3.5 H2O as raw materials.The bismuth doped TiO2 thin films were characterized by means of TG-DTA,XRD,electrochemical workstation and the ultraviolet-visible spectrophotometer (UV-vis).The results of cyclic vohammetric analysis show that doped films have three cathodic reduction peaks and larger peak flow values.The maximum coloration efficiency (CE) of undoped and bismuth doped TiO2 thin films are 3.08 cm2· C-1,6.17 cm2 · C-1,respectively.A small amount of bismuth doped can make octahedral structure of the TiO2 distort,and improve the electrochromic performance of the thin films.However,too many bismuth ions may aggregate at the grain boundary of the substrate,which increases the migration resistance of the lithium ions,even blocking the lithium ions into the TiO2 layer.The undoped and bismuth doped TiO2 gel have good thermal stability at 400 ℃.The powders transform into anatase when the heating temperature reaches to 500 ℃,and the higher the doping amount,the higher the degree of amorphization.