We report on the design and photovoltaic performance of nanostructured three dimensional (nano-3D) solar cells with ultrathin amorphous hydrogenated silicon (a-Si:H) absorber layers. Zinc oxide (ZnO) nanorods are employed as the building blocks for the nano-3D solar cells. The ZnO nanorods with controlled morphology are prepared by aqueous solution deposition at 80°C. The nanorod a-Si:H solar cells are realized by depositing n-i-p a-Si:H layers over Ag-coated ZnO nanorods. The photovoltaic performance of the nano-3D solar cells is experimentally demonstrated. With an ultrathin absorber layer of only 25 nm, an efficiency of 3.6% and a short-circuit current density of 8.3 mA/cm2 are obtained, significantly higher than values achieved for the planar or even the textured counterparts with a three times thicker (~75 nm) a-Si:H absorber layer. By increasing the absorber layer thickness in the nano-3D solar cells from 25 nm to 75 nm, the efficiency improved from 3.6% to 4.1% and the short-circuit current density increased from 8.3 mA/cm2 to 13.3 mA/cm2. The orthogonalization of the light path and the carrier transport path plays an important role in these nano-3D devices.
|Title of host publication||Proceedings of the 37th IEEE Photovoltaic Specialists Conference, 19-24 June 2011, Seattle, WA|
|Place of Publication||Piscataway|
|Publisher||Institute of Electrical and Electronics Engineers|
|Publication status||Published - 2011|