CdS/ZnO-Nanorod as Novel Window Layer for Solar Cell Application

摘要

Vertically aligned ZnO nanorods were deposited onto chemical bath deposited CdS (CBD-CdS) films for window layer application in solar cells. The composite films were characterized by measuring microstructural, optical, Raman and photoluminescence (PL) properties. All the ZnO films deposited on CBD-CdS were vertically aligned. The value of the band gap of as-deposited CBD-CdS/ZnO nanorods was found to be ～3.19 eV which changed marginally to 3.14 eV upon annealing. Fourier transformed infrared (FTIR) spectra indicated the existence of distinct characteristic absorption peak at ～478 cm~(-1) for Zn-O stretching modes. The Raman spectra of the annealed CBD-CdS/ZnO nanorods indicated only two characteristic peaks at ～303 cm~(-1) and 602 cm~(-1). The PL spectra indicated that the strong peaks located at ～2.07 eV for CBD-CdS and at ～3.15 eV for ZnO nanorods are suppressed considerably in CBD-CdS/ZnO nanorod films. The PL spectra for CBD-CdS/ZnO nanorod films consisted of peaks located at ～2.13 eV, ～2.63 eV, ～2.95 eV and ～3.4 eV arising due to transitions related to different DA transitions.