Sensitization of ZnO nanowire arrays with CuInS2 for extremely thin absorber solar cells

Abstract

We report on the photosensitization of electrodeposited ZnO nanowire arrays with CuInS2 (CIS) extremely thin layers prepared by two methods: successive ionic layer adsorption and reaction (SILAR) and electrochemical deposition (ECD). This is the first time that such core (ZnO)/shell (CIS) nanostructures are realized. Using SILAR method, 20 nm thick films composed of CIS nanoparticles are grown after 15 deposition cycles. The final layer thickness when prepared by SILAR technique depends on the number of deposition cycles and is used as a main parameter to control it. For the electrodeposited CIS films the passed charge density during deposition is used for monitoring the film thickness. These room-temperature solution based methods (SILAR and ECD) appear to be very suitable for preparing good quality, thin uniform (in nanometer scale) films of absorbing materials.