以水稻秆为生物模板制备仿生TiO_(2)及其催化性能

Preparation of Bionic TiO_(2) from Rice Straw and its Catalytic Performance

以水稻秆为生物模板,结合溶胶—凝胶法制备仿生TiO_(2),以亚甲基蓝的催化降解为目标,考察仿生TiO_(2)制备工艺优化策略及光催化活性。研究发现:当水稻秆粉末掺杂量为1.75 g,煅烧温度为500℃,煅烧时间为5 h,在太阳光下照射30 min时,亚甲基蓝的降解率高达93%以上。通过场发射扫描电镜带能谱仪、X射线衍射仪、X射线光电子能谱仪和紫外—可见分光光度计对仿生TiO_(2)样品进行表征,结果显示:1)仿生TiO_(2)复制了水稻秆多层片状立体结构,增大了比表面积,实现了N、P等元素的掺杂;2)仿生TiO_(2)形成了新的杂质能级,禁带宽度窄化了0.04 eV,光吸收边带发生红移,光催化性能进一步提升。

By combining with sol-gel method,bionic TiO_(2)was prepared by using rice straw as the biological template.Aiming at the catalytic degradation of methylene blue,the preparation process optimization strategy and photocatalytic activity of bionic TiO_(2)were investigated.Findings:the degradation rate of methylene blue is over 93%when the rice straw powder doping amount is 1.75 g,the calcination temperature is 500℃,the calcination time is 5 h,and the sunlight is irradiated for 30 min.The bionic TiO_(2)samples were characterized by field emission scanning electron microscopy,X-ray diffractometer,X-ray photoelectron spectroscopy and UV-visible spectrophotometer.Results:1)the bionic TiO_(2)replicates the multi-layered three-dimensional structure of rice straw,increases the specific surface area,and realizes the doping of elements such as N and P;2)in the bionic TiO_(2),a new impurity energy level is formed,the band gap is narrowed by 0.04 eV,and the light absorption sideband is red-shifted,by which its photocatalytic performance is further improved.