This work presents the structural, morphological and photocatalytic properties of pure SrTiO₃ (STO) and Bismuth doped STO. Several Bi doped samples were synthesized using Bi concentrations from 0.5 to 5 mol% and the sol-gel method. According to the X-ray diffraction analysis, all the samples presented cubic phase. The Scanning electron microscopy (SEM) showed that the samples without dopant or with low Bi concentration (0 and 0.5 mol%) presented a quasi-spherical morphology. The sample doped with 1 mol% of Bi presented mainly a rod-like morphology, while the samples doped with 2 and 5 mol% showed a mixture of quasi-cubic particles and rod-like particles. The absorbance experiments demonstrated that the introduction of Bi in the STO host extended the light absorption in the visible region and decreased the band gap of STO. Both effects benefited the photocatalytic properties of STO:Bi powders. In fact, the photocatalytic evaluation of the STO and STO:Bi powders under natural solar light revealed that total degradation of methylene blue (MB) can be produced only by the sample doped with 1 mol%. Scavenger experiments were also carried out using teraphtalic acid and benzoquinone in order to figure out which oxidizing agent (OH· radicals or O₂⁻) is producing the degradation of MB dye and found that the OH· radicals are the dominant agent. Since the STO:Bi powders can be activated by solar light for the photocatalytic degradation of MB, these powders could be a low cost option for the degradation of dyes in water treatment plants.

这项工作提出了纯SrTiO ₃的结构，形态和光催化性能（STO）和铋掺杂的STO。使用0.5至5mol％的Bi浓度和溶胶-凝胶法合成了几个Bi掺杂的样品。根据X射线衍射分析，所有样品呈立方相。扫描电子显微镜（SEM）表明，没有掺杂剂或Bi浓度低（0和0.5mol％）的样品呈现准球形的形态。掺杂有1 mol％的Bi的样品主要呈棒状形态，而掺杂有2 mol％和5 mol％的样品则显示出准立方颗粒和棒状颗粒的混合物。吸光度实验表明，在STO主体中引入Bi可以延长可见光区域的光吸收，并减小STO的带隙。两种作用均有益于STO：Bi粉末的光催化性能。事实上，在自然光下对STO和STO：Bi粉末的光催化评估表明，只有掺杂1 mol％的样品才能产生亚甲基蓝（MB）的总降解。还使用四邻苯二甲酸和苯醌进行了清除剂实验，以便确定哪种氧化剂（OH·自由基或O₂ ^- ）是生产MB染料的降解，发现OH·自由基是占主导地位的代理。由于STO：Bi粉末可以被太阳光激活以进行MB的光催化降解，因此这些粉末可能是水处理厂中染料降解的低成本选择。