Modeling Charge Mobility in Nanoparticle Solar Cells

Nanoparticle (NP) solar cells show the promise to enhance the efficiency of solar cells over the Shockley-Queisser limit due to quantum confinement enhanced charge multiplication processes [1]. A fundamental challenge of NP solar cells, however, is that the very reason that leads to enhanced charge generation also tends to hinder charge transport. To address this challenge, we outline a multi-scale transport modeling scheme based on our previous calculations [2] that involves determining NP parameters from ab-initio and semi-empirical calculations, such as energy level structures, charging energies. This is then embedded in a Kinetic Monte Carlo hopping transport framework to calculate electron and hole mobilities in NP devices as a function composition, disorder, temperature. As a first demonstration, we apply our method to PbSe NP Schottky devices.\\[4pt] Work done in collaboration with Ian Carbone, Physics Department, University of California, Santa Cruz and Marton Voros, Physics Department, University of California, Davis.\\[4pt] [1] Matthew C. Beard et al., Acc. Chem. Res. 46, 1252 (2013).\\[0pt] [2] Ian Carbone, S.A. Carter, G.T. Zimanyi, accepted in J. of Appl. Phys.