Abstract
We fabricated zinc oxide (ZnO) nanorods (NRs) with Al-doped ZnO (AZO) seed layers and dye-sensitized solar cells (DSSCs) employed the ZnO NRs between a TiO2 photoelectrode and a fluorine-doped SnO2 (FTO) electrode. The growth rate of the NRs was strongly dependent on the seed layer conditions, i.e., thickness, Al dopant and annealing temperature. Attaining a large particle size with a high crystallinity of the seed layer was vital to the well-aligned growth of the NRs. However, the growth was less related to the substrate material (glass and FTO coated glass). With optimized ZnO NRs, the DSSCs exhibited remarkably enhanced photovoltaic performance, because of the increase of dye absorption and fast carrier transfer, which, in turn, led to improved efficiency. The cell with the ZnO NRs grown on an AZO seed layer annealed at 350 °C showed a short-circuit current density (JSC) of 12.56 mA/cm2, an open-circuit voltage (VOC) of 0.70 V, a fill factor (FF) of 0.59 and a power conversion efficiency (PCE, η) of 5.20% under air mass 1.5 global (AM 1.5G) illumination of 100 mW/cm2.
Highlights
Zinc oxide (ZnO) is one of the most attractive II–VI semiconductor oxide materials, because of its wide resistivity range (10−4–1012 ·cm), direct wide band gap (3.37 eV) and large exciton binding energy (60 meV) at room temperature [1,2,3,4,5]
ZnO NRs grown on the Al-doped ZnO (AZO) seed layer show a stronger diffraction peak corresponding to the (002) plane growing along the c-axis perpendicular to the substrate surface; weak (100), (101), (102) and (110) peaks are observed
NRs grown on the AZO seed layer was approximately 200 nm, which is two times longer than NRs grown on the undoped ZnO seed layer
Summary
Zinc oxide (ZnO) is one of the most attractive II–VI semiconductor oxide materials, because of its wide resistivity range (10−4–1012 ·cm), direct wide band gap (3.37 eV) and large exciton binding energy (60 meV) at room temperature [1,2,3,4,5]. Reported that the length of Li-doped ZnO NRs increased with an increase in the thickness of the sputtered undoped ZnO seed layer [9]. It was reported that the crystallinity, surface morphology, thickness and preparation conditions of the undoped ZnO seed layer played an important role on the growth of the ZnO NRs [10,11,12,13,14]. The effects of the doped ZnO seed layer on the structural properties of the ZnO NRs have rarely been reported. We investigated the structural properties of ZnO nanostructures (nanorods, plate-like, flower-like) grown on an Al-doped ZnO (AZO) seed layers prepared by a sol-gel solution process on different substrate materials
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
