Improving the performance of ternary organic solar cells using metal oxides as charge-transport layers

Abstract

In this study, we improved the performance of ternary organic solar cells (OSCs) using metal oxides (p-type NiO_x and n-type SnO₂) as the charge-transport layers (CTLs). The use of NiO_x and SnO₂ can facilitate charge transportation and suppress charge recombination in PM6:IDIC:Y6-based ternary OSCs, which is beneficial for boosting their performance. As a result, the OSCs with CTLs of NiO_x and SnO₂ exhibited an improved power conversion efficiency (PCE) of 16.2% (on average), which is higher than that (15.1%) of the control OSCs using poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) and LiF as the CTLs. The stability of the OSCs was simultaneously improved with the PCE degradation significantly suppressed upon using NiO_x and SnO₂. After 10 days of storage and measurement under ambient conditions, the PCE degradation was dramatically decreased from 49.7% to 20.3%, which was induced by the high intrinsic stability of NiO_x and SnO₂. The best OSC using the CTLs of NiO_x and SnO₂ showed a champion PCE of 16.6%, with a stable power output and negligible hysteresis.