Despite great challenges, the development of new molecular structures with multiple and even conflicting characteristics are eagerly pursued for exploring advanced applications. To develop high-performance chiral organic semiconducting molecules, a distorted π-system is required for strong coupling with circularly polarized light (CPL), whereas planar π-stacking systems are necessary for high charge-carrier mobility. To address this dilemma, in this work, we introduce a skeleton merging approach through distortion of a perylene diimide (PDI) core with four fused heteroaromatics to form an ortho-π-extended PDI double-[7]heterohelicene. PDI double helicene inherits a high dissymmetry factor from the helicene skeleton, and the extended π-planar system concurrently maintains a high level of charge transport properties. In addition, ortho-π-extension of the PDI skeleton brings about near-infrared (NIR) light absorption and ambipolar charge transport abilities, endowing the corresponding organic phototransistors with high photoresponsivity of 450 and 120 mA W−1 in p- and n-type modes respectively, along with a high external quantum efficiency (89%) under NIR light irradiations. Remarkably, these multiple characteristics enable high-performance broadband CPL detections up to NIR spectral region with chiral organic semiconductors.

Chiral supramolecules have great potential for use in chiral recognition, sensing, and catalysis. Particularly, chiral supramolecular biocoordination polymers (SBCPs) provide a versatile platform for characterizing biorelated processes such as chirality transcription. Here, we selectively synthesize homochiral and heterochiral SBCPs, composed of chiral naphthalene diimide ligands and Zn ions, from enantiomeric and mixed R-ligands and S-ligands, respectively. Notably, we find that the chiral self-sorted SBCPs exhibit multifunctional properties, including photochromic, photoluminescent, photoconductive, and chemiresistive characteristics, thus can be used for various sensors. Specifically, these materials can be used for detecting hazardous amine materials due to the electron transfer from the amine to the SBCP surface and for enantioselectively sensing a chiral species naproxen due to the different binding energies with regard to their chirality. These results provide guidelines for the synthesis of chiral SBCPs and demonstrate their versatility and feasibility for use in various sensors covering photoactive, chemiresistive, and chiral sensors.

Chiral organic optoelectronics using circularly polarized light (CPL) as the key element in the photonic signal has recently emerged as a next-generation photonic technology. However, it remains challenging to simultaneously achieve high polarization selectivity and superior optoelectronic performance. Supramolecular two-dimensional (2D) chiral organic single crystals may be good candidates for this purpose due to their defect-free nature, molecular diversity, and morphologies. Here, quasi-2D single crystals of chiral perylene diimides with parallelogram and triangle/hexagon morphologies have been selectively fabricated via self-assembly using different cosolvent systems. These materials exhibit amplified circular dichroism (CD) spectral signals, due to their molecular packing modes and supramolecular chirality. Through molecular surface n-doping using hydrazine, chiral single crystals exhibit electron mobility surpassing 1.0 cm 2 V −1 s −1 , which is one of the highest among chiral organic semiconductors, and excellent optoelectronic functions. Theoretical calculations reveal that the radical anions formed by n-doping increase the electron affinity and/or reduce the energy gap, thus facilitating electron transport. More importantly, the doped organic chiral crystals selectively discriminate CPL handedness with a high anisotropy factor of photoresponsivity (∼0.12). These results demonstrate that surface-doped quasi-2D chiral organic single crystals are highly promising for chiral optoelectronics.

This study investigates the performance of single-crystalline nanomaterials of wide-band gap naphthalene diimide (NDI) derivatives with methylene-bridged aromatic side chains. Such materials are found to be easily used as high-performance, visible-blind near-UV light detectors. NDI single-crystalline nanoribbons are assembled using a simple solution-based process (without solvent-inclusion problems), which is then applied to organic phototransistors (OPTs). Such OPTs exhibit excellent n-channel transistor characteristics, including an average electron mobility of 1.7 cm V s, sensitive UV detection properties with a detection limit of ∼1 μW cm, millisecond-level responses, and detectivity as high as 10 Jones, demonstrating the highly sensitive organic visible-blind UV detectors. The high performance of our OPTs originates from the large face-to-face π-π stacking area between the NDI semiconducting cores, which is facilitated by methylene-bridged aromatic side chains. Interestingly, NDI-based nanoribbon OPTs exhibit a distinct visible-blind near-UV detection with an identical detection limit, even under intense visible light illumination (for example, 10 times higher intensity than UV light intensity). Our findings demonstrate that wide-band gap NDI-based nanomaterials are highly promising for developing high-performance visible-blind UV photodetectors. Such photodetectors could potentially be used for various applications including environmental and health-monitoring systems.