Layer-by-Layer Processed Organic Solar Cells

• Published in: Advanced energy materials 2016-09, Vol.6 (17), p.np-n/a
• Main Authors: Wang, Yifan, Zhan, Xiaowei
• Format: Article
• Language: English
• Subjects: Blends; Charge; Current carriers; Deposition; Excitons; layer-by-layer processes; organic photovoltaics; Phase separation; Photovoltaic cells; sequential processes; Solar cells; solution processes; vacuum deposition
• ISSN: 1614-6832; 1614-6840
• DOI: 10.1002/aenm.201600414

Layer‐by‐layer (LL) processes, i.e., sequential deposition of different active layers, are widely used in the fabrication of organic solar cells (OSCs). Recently, LL vacuum deposition and LL solution processes have attracted considerable attention. LL processing presents some advantages over the blend method: a) donor and acceptor layers can be easily and independently controlled and optimized; b) the charge carriers dissociated from excitons at the donor–acceptor interface are confined to each phase, so bimolecular recombination losses can be reduced; c) bilayer geometries enable an easier way for understanding the physical processes taking place at the donor–acceptor interface; d) desired vertical phase separation for charge extraction can be obtained through changing the sequence of donor and acceptor deposition. This report summarizes the recent developments of LL processed OSCs. The remaining problems and challenges, and the key research direction in near future are discussed. Layer‐by‐layer (LL) processing techniques exhibit some advantages over the traditional blend‐casting technique in organic solar cells. The recent developments of LL vacuum‐deposited and solution‐processed solar cells are summarized.