Enhanced efficiency of polymer solar cells by structure-differentiated silver nano-dopants in solution-processed tungsten oxide layer

In this article, we creatively incorporate naked Ag nanoparticles (nAgp), SiO2-covered Ag nanoparticles (SiAgp), and naked Ag nanoplates (nAgPl) into solution-processed tungsten oxide (WO3) hole transport layer in polymer solar cells (PSCs) to increase the light absorption through localized surface plasmon resonance (LSPR) effect. With optimized doping concentrations, nAgp decreases power conversion efficiency (PCE), however, SiAgp increases PCE by 13.2% and nAgPl increases PCE by 19.7%. In detail, the great PCEs discrepancies are mainly caused by the discrepancies of short circuit currents (J(sc)). The experiments results indicate that the naked surface of nAgp causes the exciton-quenching to decrease the J(sc) of PSCs. Whereas the capsulation of SiO2 at the surface of nAgp and the embedment of nAgPl in WO3 layer can prevent the exciton-quenching and help to use LSPR effect of Ag nano-dopants to enhance the J(sc) of PSCs. Crown Copyright (C) 2016 Published by Elsevier B.V. All rights reserved.