球形花状ZnO微-纳分级结构的制备及其光电化学性能

文章采用一种热蒸发的方法在镀有Zn膜的掺F的SnO2(FTO)导电玻璃上制备出球形花状ZnO微-纳米分级结构,利用SEM、XRD、PL等手段对球形微-纳米结构的形貌、成分和发光性能进行了分析。分析结果表明,球形花状六方纤锌矿ZnO微-纳米分级结构具有表面多孔特征,有利于染料的吸收。球形花状ZnO微-纳米结构存在近带边发射的近紫外发光(402nm)和来自于深能级缺陷的可见发光(460nm和500nm)。将所制备的样品作为光阳极组装成染料敏化太阳能电池(DSSC),该电池的转换效率η=0.67%,比以纳米棒、树枝状纳米结构、纳米梳作为光阳极材料的DSSC的转换效率要高,但是整体转换效率不高,这是由于晶体内部较多缺陷引起的。

Micro-nano hierarchical ZnO with spherical flower-like structure:fabrication and photoelectrical properties

In this paper,a spherical flower-like ZnO micro-nano hierarchical structure was successfully grown via thermal evaporation method on F-doped SnO2(FTO) conductive glass coated with Zn.The morphology,composition and luminescence properties of the spherical micro-nano hierarchical structure were characterized by field emission scanning electron microscopy(FESEM),powder X-ray diffraction(XRD) and photoluminescence spectroscopy(PL) respectively.The results reveal that the spherical flower-like wurtzite ZnO micro-nano hierarchical structure is of porous surface which enhances the dye absorbing.The PL measurement exhibits that the as-synthesized products have near-UV emission peaks of 402 nm and visible emission peaks of 460 nm and 500 nm due to near band-edge emission and deep level defects respectively.Dye-sensitized solar cells(DSSC) were assembled by using the ZnO as anode material.A conversion efficiency η=0.67% was obtained,which was higher than those of nanorods,nanobranches and nanocombs based anode materials.However the deep level defects and porous surface influenced the final conversion efficiency.