Transferable Graphene Oxide by Stamping Nanotechnology: Electron-Transport Layer for Efficient Bulk-Heterojunction Solar Cells

摘要

Donor-acceptor-blended bulk-heterojunction (BHJ) solar cells fabricated by low-cost printing technology offer a number of advantages: They are robust, lightweight, and flexible and can be produced in large area by roll-to-roll manufacturing. During recent years, there have been significant improvements in power conversion efficiency (PCE) in BHJ solar cells because of the synthesis of specific polymers and small molecules, the achievement of improved nanomorphology through process control (by processing additives), and the use of new architectures (e.g., the inverted structure with specific transport layers). The electron-transport layer (ETL) plays an especially important role in enhancing the PCE with increased short-circuit current density (J_(SC)), and fill factor (FF) in the device because of improved charge transport and charge extraction. Moreover, the ETL affects device stability as an oxygen scavenger that can protect against degradation of BHJ in air.