Position Dependent Impact of Plasmonic Nanocubes on the Optical Performance of Perovskite Solar Cells: A Simulation

A plasmon enhanced semitransparent planar perovskite (CH3NH3PbBrxI3-x, x = 0 to 1) solar cell with plasmonic silver nanocube (Ag NC) array is studied using finite difference time domain (FDTD) analysis. The NC array is positioned at either of two sites of the cell, namely at the back contact layer wrapped by transparent electrode and at the absorber layer. The comparative analysis is performed for light absorption enhancement as well as transparency for different NC sizes and NC distances along with various composition of the perovskite material at a fixed absorber thickness. With the investigation of local field concentration and extinction cross-section of the NCs as well as the absorption pattern of the cell for both NC locations it is found that, for both cases the enhancement is achieved by red shifting the band edge. However, higher absorption enhancement can be obtained for cells with plamonic NCs at back contact which is more pronounced for smaller NC size, attributed by the strong electrode coupling effect. In contrast, cells with NCs at the absorber is found to provide better transparency at a fair level of absorption enhancement. Thus, this work provides a comprehensive optical analysis of typical perovskite solar cells with the incorporation of plasmonic metal nanostructures.