作　　者： ;

机构地区： 广州大学

出　　处： 《高等学校化学学报》 2019年第10期2081-2089,共9页

摘　　要： 采用粒径为25 nm的锐钛矿和金红石型混合相二氧化钛(TiO2)材料(P25)替代常规锐钛矿型TiO2,制备了基于石墨氮化碳(g-C3N4)/混合相TiO2(g-C3N4/P25)的可见光激发光电敏感体系.研究结果表明,石墨氮化碳(g-C3N4)大的平面结构不仅能够成为TiO2纳米材料合适的高分散载体,其高效载流子传输能力还赋予了复合体系优异的光电性能.当g-C3N4掺杂质量分数仅为0.5%时,复合体系的光电流响应信号可提高至原来的4.5倍,增敏效果最好.该光敏体系的研制显著简化了制备工艺并降低了成本,同时有效提高了体系的可见光利用效率.基于该g-C3N4/P25光电敏感复合体系,首次采用光电化学方法实现了中草药抗氧化容量的测定,为量化中药体系抗氧化性能评估提供了新的思路. Chinese herbal medicines are rich in resources and can be found in various types.The efficacy of some Chinese herbal medicines are closely related to their antioxidant effects.Therefore,the rapid and accurate evaluation of the antioxidant capacity is the foundation for the scientific utilization of Chinese herbal medicine resources.By replacing the conventional titanium dioxide(TiO2)nanomaterials with the P25(the 25 nm anatase and rutile mixed phase titanium dioxide material),the graphitic carbon nitride(g-C3N4)/P25 nanocomposite-based sensitive visible light photoelectrochemical platform has been reported herein.In this system,not only the large planar of g-C3N4can serve as a highly-dispersed carrier for the TiO2nanomaterials,but also its highly efficient carrier transport capability can endow the composite material with excellent photoelectronchemical performance.The sensitization effect of g-C3N4with a mass ratio of only 0.5%is the best,and the photocurrent response signal of the composite material can be increased by 4.5-fold when compared with the conventional TiO2 nanomaterials.A good photoelectrochemical signal response can still be obtained under the open circuit potential,which provides a research basis for the construction of the two-electrode system.In comparison with previous reports,the photoelectrochemical strategy not only greatly simplifies the preparation process and reduces the cost,but also effectively improves the visible light utilization efficiency.This method was used for the first time to evaluate the antioxidant capacity of traditional Chinese herbal medicines which provided a new avenue for quantifying the antioxidant performance evaluation of traditional Chinese herbal medicines.

关 键 词： 抗氧化 氮化碳 二氧化钛 光电化学 中草药

领　　域： []