Low cost fabrication of semiconducting materials for photovoltaic applications

The present study is divided in two parts. In the first part, the electrochemical deposition of ZnO 2D layers and nanowires and their photosensitization with extremely thin absorbing layers of CdS, CdTe, CuInS₂ (CIS) and Cu₂ZnSnS₄ (CZTS) is discussed. The photosensitizing semiconductors are prepared by close space sublimation (CSS, used for CdTe deposition), Successive Ionic Layer Adsorption and Reaction (SILAR) and electrodeposition techniques. It is shown that the SILAR method appears as very suitable for the formation of very thin and uniform films around ZnO nanowires and only few SILAR deposition cycles are enough to achieve good absorbance in the visible spectral wave range. In the second part the integration of these materials in extremely thin absorber (eta) and hybrid solar cells is presented. In this part is also discussed the electrochemical deposition of CuSCN which is used in these photovoltaic devices as hole transporting layer. Our results clearly show that the integration of electrodeposited ZnO 2D layers improves considerable the stability of inverted polymeric solar cells.