Control over the aggregated structure of donor–acceptor conjugated polymer films for high‐mobility organic field‐effect transistors

Abstract

Donor–acceptor (D‐A) conjugated polymers have demonstrated great potential in organic field‐effect transistors application, and their aggregated structure is a crucial factor for high charge mobility. However, the aggregated structure of D‐A conjugated polymer films is complex and the structure–property relationship is difficult to understand. This review provides an overview of recent progress in controlling the aggregated structure of D‐A conjugated polymer films for higher mobility, including the mechanisms, methods, and properties. We first discuss the multilevel microstructures of D‐A conjugated polymer films, and then summarize the current understanding of the relationship between film microstructures and charge transport properties. Subsequently, we review the theory of D‐A conjugated polymer crystallization. After that, we summarize the common methods to control the aggregated structure of semi‐crystalline and near‐amorphous D‐A conjugated polymer films, such as crystallites and aggregates, tie chains, film alignment, and attempt to understand them from the basic theory of polymer crystallization. Finally, we provide the current challenges in controlling the aggregated structure of D‐A conjugated polymer films and in understanding the structure–property relationship.

Manipulation of Nonradiative Process Based on the Aggregation Microenvironment to Customize Excited-State Energy Conversion

“…Other than being suppressed for high-efficiency luminescence, nonradiative processes are closely related to other excited-state energy conversions, such as photothermal and photochemical conversions, which play important roles in exploring advanced functional materials for biomedicine and energy utilization. ,,,, For example, ultrafast IC and VR for heat generation are considered as promising strategies for tumor elimination and water evaporation. − Effective photochemical conversion based on ISC, ET, and eT has been employed to cancer treatment and energy utilization. ,,,, Therefore, based on the ultrasensitivity of the nonradiative processes to the AME, understanding the pivotal nonradiative processes and developing their corresponding manipulation strategies based on the characteristic aggregation to customize excited-state energy conversion are currently drawing great attention.…”

Alleviating excessive aggregation of a non-fullerene acceptor by delaying and shortening the crystallization time to reduce the energy loss of ternary organic solar cells

“…OSCs offer numerous advantages, including low production costs, lightweight nature, and ability to be fabricated on flexible substrates. 1–4 Although the highest PCE of single-junction OSCs has reached 19.6%, 5 the PCE of OSCs is still lower than that of traditional silicon-based and perovskite solar cells. 6 Unlike the direct formation of electrons and holes in inorganic and perovskite solar cells, the excitons in organic semiconductors have strong Coulombic binding energy (≈0.5 eV).…”

Tuning the Aggregated Structure of Polymer Interlayers for High-Performance Quantum Dot Solar Cells and Photodetectors

“…In terms of devices like photovoltaic cells and photodetectors, the face-on orientation represents the optimal molecular stacking configuration for facilitating carrier transport. 23 devices. Real-space microscopic techniques, such as transmission electron microscopy (TEM) and atomic force microscopy (AFM), are used to demonstrate the correlations between the structure and properties.…”

“…These patterns result in different molecular stacking orientations, such as face-on orientation, edge-on orientation, and flat-on orientation. In terms of devices like photovoltaic cells and photodetectors, the face-on orientation represents the optimal molecular stacking configuration for facilitating carrier transport . Various characterization methods have been utilized to elucidate the impact of the mechanism of the microscopic morphology of conjugated polymers on the performance of optoelectronic devices.…”