A depth behavioral understanding for each layer in perovskite solar cells (PSCs) and their inter[acial interactions as a whole has been emerged for further enhancement in power conversion efficiency (PCE). Herein, NiO@Carbon was not only simulated as a hole transport layer but also as a counter electrode at the same time in the planar heterojunction based PSCs with the program wxAMPS (analysis of microelectronic and photonic structures)-lD. Simulation results revealed a high dependence of PCE on the effect of band offset between hole transport material (HTM) and perovskite layers. Meanwhile, the valence band offset (AEv) of NiO-HTM was optimized to be -0.1 to -0.3 eV lower than that of the perovskite layer. Additionally, a barrier cliff was identified to significantly influence the hole extraction at the HTM/absorber interface. Conversely, the AEv between the active material and NiO@Carbon-HTM was derived to be -0.15 to 0.15 eV with an enhanced efficiency from 15% to 16%.
The interface between graphene and organic layers is a key factor responsible for the performance of graphene-based organic solar cells(OSCs). In this paper, we focus on coating PEDOT:PSS onto the surface of graphene. We demonstrate two approaches, applying UV/Ozone treatment on graphene and modifying PEDOT:PSS with Zonyl, to get a PEDOT:PSS well-coated graphene film. Our results prove that both methods can be effective to solve the interface issue between graphene and PEDOT: PSS. Thereby it shows a positive application of the composited graphene/PEDOT:PSS film on graphene-based OSCs.