Theoretical limit of power conversion efficiency for organic and hybrid halide perovskite photovoltaics

We calculated the maximum power conversion efficiency as a function of the optical band gap for organic photovoltaic (PV) cells by assuming that charge separation is accompanied by the energy loss required to dissociate strongly bound charge pairs. The dissociation energy can be estimated from the relationship between the open circuit voltage (V-OC) and the optical band gap (E-g). By analyzing the published data on V-OC and E-g, the dissociation energy can be estimated. The result could be used as a guide for selecting donor and acceptor materials. We also studied the theoretical limit of power conversion efficiency of hybrid halide perovskite by taking into account the energy loss involved in the carrier transfer from the perovskite phase to the metal oxide charge transport layer. (C) 2015 The Japan Society of Applied Physics