The primary goal of the project is the demonstration of a small area, 15% efficient thin film solar cell which is free of Cd and Se and uses a small number of elements. This goal shall be achieved by a CuInS2 based solar cell (SULFURCELL). The avoidance of Cd and Se and the restriction of the number of different elements incorporated in the cell will reduce production and recycling costs as well as environmental impacts.
Development and optimization will be performed on all constituent components of the cell, i.e. substrate, backcontact, absorber, buffer and transparent front contact. The ternary chalcopyrite CuInS2 has an optimum band-gap and potential for high efficiency and high open circuit voltages facilitating the module design. Extrinsic doping and growth assistance will be used to improve the opto-electronical properties of CuInS2 as required for the project's goal. Cd free buffer layers with a suitable conduction band alignment to CuInS2 have to be developed. Novel concepts such as aerosol based techniques, spin coating and band-gap engineering by quantum confinement will be pursued. Transparent conductive oxides such as ZnO, ITO and SnO, deposited by sputtering or MOCVD are used as front contacts after optimization of transparency, conductivity and haze. Valuable input for these tasks is expected from characterization methods such as transmission electron microscopy, Raman spectroscopy and secondary ion mass spectroscopy. The material science aspects will be supplemented by the investigation of topics especially important for scaling-up and commercial exploitation, e.g.
substrate and patterned back-contact cost reduction, encapsulation and stability tests. The results of all sub-tasks will be used as input for an exploitation study.
Funding SchemeCSC - Cost-sharing contracts
80055 Portici Napoli
OX1 3PJ Oxford