Desirable Uniformity and Reproducibility of Electron Transport in Single‐Component Organic Solar Cells

Abstract

Despite the simplified fabrication process and desirable microstructural stability, the limited charge transport properties of block copolymers and double‐cable conjugated polymers hinder the overall performance of single‐component photovoltaic devices. Based on the key distinction in the donor (D)–acceptor (A) bonding patterns between single‐component and bulk heterojunction (BHJ) devices, rationalizing the difference between the transport mechanisms is crucial to understanding the structure–property correlation. Herein, the barrier formed between the D–A covalent bond that hinders electron transport in a series of single‐component photovoltaic devices is investigated. The electron transport in block copolymer‐based devices is strongly dependent on the electric field. However, these devices demonstrate exceptional advantages with respect to the charge transport properties, involving high stability to compositional variations, improved film uniformity, and device reproducibility. This work not only illustrates the specific charge transport behavior in block copolymer‐based devices but also clarifies the enormous commercial viability of large‐area single‐component organic solar cells (SCOSCs).

Unraveling High Reproducibility and Broad Composition Tolerance in High‐Efficiency Organic Solar Cells via Sequential Deposition

“…The high hole mean mobility implies improved hole transport process and efficient hole extraction at the electrode interface. [ 33 ] Besides, the c v of hole mobility in PM6:L8‐BO, PM6:BTP‐eC9, and PM6:Y6 systems with LBL structure are 42.4%, 60.5%, and 25.5%, which is significantly lower than the corresponding BHJ structure devices (49.1%, 100.0%, and 48.3%, respectively). In addition, a series of electron‐only devices were fabricated with the structure of ITO/Al/active layer/PDINN/Ag, and the layer of Al acts as the hole blocking layer.…”

Ultrafast Exciton Dissociation in Block Copolymer toward Efficient Single Material Organic Solar Cells

“…We have chosen the PS as the solvent matrix because it was demonstrated to sustain the extended conformation of dispersed polymers and have minor effects on their electronic properties. [ 60,61 ] Its dielectric constant is close to that of PBDB‐T and PTY6, which ensures low polarity to have a small impact on the charge dynamics. [ 62–64 ]…”

“…We have chosen the PS as the solvent matrix because it was demonstrated to sustain the extended conformation of dispersed polymers and have minor effects on their electronic properties. [60,61] Its dielectric constant is close to that of PBDB-T and PTY6, which ensures low polarity to have a small impact on the charge dynamics. [62][63][64] A similar behavior of k diss is found in the other block copolymer (PBDB-T-b-PIDIC2T) and blend (PBDB-T:PIDIC2T) film (See structure in Figure S8a, Supporting Information).…”

Stable block copolymer single-material organic solar cells: progress and perspective

“…The connected D and A blocks combine the functions of the photophysics process in a single system, which leads to different charge transport properties between the BCP and BHJ blend. 152,153 Photogenerated charge carriers originating from the donor or the acceptor block can be transferred within the region of the conjugated backbone. Sufficient interface for exciton dissociation and continuous channels for charge transport are expected to be realized in BCP films through their ordered nanostructure via self-assembly.…”