Affiliation:
1. Department of Physics Center for Materials Science and Nanotechnology University of Oslo P.O.Box 1048 Blindern Oslo N‐0316 Norway
2. Department of Solar Energy Materials and Technologies Institute for Energy Technology (IFE) Kjeller 2027 Norway
Abstract
AbstractThe novel, high electron mobility material has been investigated theoretically as an absorber in a two‐terminal tandem solar cell. In addition to its high mobility, can attain sufficiently low carrier concentration to enable ‐junctions, and has a tunable bandgap around the 1.7 eV range. It is therefore suitable for pairing with a Si‐based bottom cell. In addition to the layer, the tandem cell consists of a emitter and a Si heterojunction bottom cell. A buffer layer is introduced between the emitter and absorber in the top cell to mediate a large valence band offset that resulted in a poor fill factor, . A buffer layer bandgap of 1.5 eV gave the highest power conversion efficiency (PCE). The objective is to estimate the optimal performance of in a tandem solar cell. The dependence of current–voltage (–) characteristics on thickness, mobility and carrier concentration in the layer is evaluated, and found to yield maximum performance with 0.35 , 250 Vs–1 and , respectively. Using these conditions, the – parameters of the device under AM1.5 illumination are short circuit current density, mA , open circuit voltage, V, and . With this, it is reported on, to the best of the knowledge, the first device simulation based on .