Elaboration of ZnO nanowires by solution based method, characterization and solar cell applications

Abstract

ZnO nanowires (NWs) layers have been synthesized using a two-step chemical solution method on ITO glass substrates coated with ZnO seeds at different immersing times. The structures, morphology and optical properties of the synthesized ZnO NWs have been investigated. The prepared ZnO NWs have an obvious polycrystalline hexangular wurtzite structure and are preferentially oriented along the c-axis (002). FESEM micrographs showed that the prepared ZnO NWs are close to being vertically grown and more densely at higher immersing times. Poly [2-methoxy-5(2′-ethyl-hexyloxy)-1,4-phenylenevinylene], MEH-PPV, was used as an active layer to prepare three samples of MEH-PPV/ZnO solar cell based on ZnO NWs that were prepared at different immersing times. A maximum power conversion efficiency of 0.812% was achieved for MEH-PPV/ZnO solar cell prepared at a higher immersing time. The improved efficiency may be attributed to the enhancement of both open-circuit voltage and fill factor.

Metal Oxide Nanowires as Building Blocks for Optoelectronic Devices

“…Zinc oxide (ZnO) is an interesting eco-friendly and versatile metal oxide, suitable for many applications due to its remarkable physico-chemical properties. Being an n-type semiconductor with a direct band gap (3.37 eV), with an excitonic binding energy of 60 meV, it can be easily integrated in optoelectronic devices such as photodetectors [15], light emitting diodes [31], solar cells [32]. Additionally, its flexibility in terms of nanostructure morphology (nanowires, nanotubes, nanofibers, nanorods, nanoneedles, hexagonal nanoprisms, nanoflowers, rings, etc.)…”