Ag-CNTs-TiO_2纳米纤维在可见光区的光电转换性能研究

Photocurrent response of electrospun Ag-CNTs-TiO_2 nanofiber under visible-light irridiation

基于静电纺丝技术制备尺寸均一、性能稳定的Ag-碳纳米管(CNTs)-TiO_2复合纳米纤维。结合了纳米银颗粒的表面等离激元共振效应,有效提高了复合材料对于可见光的吸收,此外,CNTs的掺入,可以加速电子在复合材料内部的传递,降低光生电子-空穴对的重合几率。采用扫描电子显微镜(SEM),X射线衍射(XRD)和X射线能谱仪(EDS)对复合纤维进行了表征,结果证明产物为Ag-CNTs-TiO_2复合纳米纤维,且纤维分散性好、长径比大,同时掺杂均匀,实验重复性好。相比较于TiO_2和TiO_2-Ag纳米纤维,Ag-CNTs-TiO_2纳米纤维的光电转换性能明显提高。研究了CNT掺杂量对复合材料光电转换效果的影响,结果表明:掺杂10%(wt,质量分数,下同)Ag和15%CNTs的Ag-CNTs-TiO_2复合纳米纤维光电转换效率最高。

The efficient use of solar energy is one of the biggest challenges.The electrospinning technology was used to make a novel nanofiber consisting of TiO2,Ag and carbon nanotube（CNT）with desirable dispersion.The increased absorption of visible light have been originated from the surface plasmon resonance（SPR）effect of Ag nanoparticles,and the highly efficient photoelectric conversion activity was associated with fast photo-generated charge separation due to the formation of Schottky junction between TiO2 and Ag nanoparticles,as well as the high electron mobility of CNT.Compared with TiO2 and Ag/TiO2 nanofiber,the as-obtained nanofibers exhibited excellent photocurrent activity,the photocurrent of0.7μA/cm2 was immediately observed by employing Ag/CNTs/TiO2.A versatile strategy for the synthesis of novel and efficient photomaterials was provided.