Nanoribbon-shaped nanocomposites composed of conjugated polymer poly(3-hexylthiophene) (P3HT) nanoribbons and plasmonic gold nanorods (AuNRs) were crafted by a co-assembly of thiol-terminated P3HT (P3HT-SH) nanofibers with dodecanethiol-coated AuNRs (AuNRs-DDT). First, P3HT-SH nanofibers were formed due to interchain π-π stacking. Upon the addition of AuNRs-DDT, P3HT-SH nanofibers were transformed into nanoribbons decorated with the aligned AuNRs on the surface (i.e., nanoribbon-like P3HT/AuNRs nanocomposites). Depending on the surface coverage of the P3HT nanoribbons by AuNRs, these hierarchically assembled nanocomposites exhibited broadened and red-shifted absorption bands of AuNRs in nIR region due to the plasmon coupling of adjacent aligned AuNRs and displayed quenched photoluminescence of P3HT. Such conjugated polymer/plasmonic nanorod nanocomposites may find applications in fields, such as building blocks for complex superstructures, optical biosensors, and optoelectronic devices.

Semiconducting organic–inorganic nanocomposites comprising conjugated polymers (CPs) and semiconducting nanocrystals (NCs) represent an important class of functional materials. The ability to organize CPs and NCs into self-assembled nanostructures in close proximity may enable efficient charge or energy transfer between them for use in flexible electronics, light-emitting displays, and photovoltaics. Herein we report the crafting of one-dimensional (1D) functional nanocomposites composed of all-conjugated diblock copolymers and CdSe nanorods (NRs) via two consecutive self-assembly processes, namely, self-assembly of poly­(3-hexyl­selenophene)-block-poly­(3-butyl­selenophene) (denoted P3HS-b-P3BS) diblock copolymers into nanofibers, followed by self-assembly of P3HS-b-P3BS nanofibers and CdSe NRs to yield P3HS-b-P3BS–CdSe NR nanocomposites. Notably, P3HS-b-P3BS diblock copolymers are first rationally designed and synthesized, exhibiting a narrow optical bandgap and forming nanofibers due to strong interchain π–π stacking (i.e., first self-assembly). Subsequently, the addition of CdSe NRs into P3HS-b-P3BS nanofiber solution results in the formation of 1D P3HS-b-P3BS–CdSe NR nanocomposites driven by the van der Waals interaction between aliphatic ligands on the surface of CdSe NRs and the hexyl side chains of P3HS-b-P3BS and the coordination interaction between the selenium of P3HS and the surface of CdSe NRs (i.e., second self-assembly). Quite intriguingly, an integrated Monte Carlo simulation and experimental study reveals that CdSe NRs are aligned parallel to the long axis of P3HS-b-P3BS nanofibers in an end-to-end mode at low concentration of CdSe. When high concentration of CdSe NRs is introduced, coexistence of the side-by-side and layer-by-layer assemblies of CdSe NRs along P3HS-b-P3BS nanofibers is yielded. Photoluminescence quenching of CdSe NRs is observed, suggesting an efficient charge transfer between CdSe and P3HS-b-P3BS. Such self-assembled conjugated diblock copolymer–quantum rod nanocomposites may find applications in optics, optoelectronics, and sensors.

The use of mixed solvents provided an effective way to control the self-assembly behavior and photophysical properties of a conjugated rod-coil block copolymer, poly(3-hexylthiophene)-b-poly(ethylene oxide) (P3HT-b-PEO). It was shown that the balance between the p-p stacking of the P3HT and microphase separation of the copolymer could be dynamically controlled and shifted by solvent blending. Depending on the mixed solvent ratio (i.e., chloroform/methanol, anisole/chloroform, or anisole/methanol), the copolymer chains experienced different kinetic pathways, yielding a series of nanostructures such as disordered wormlike pattern, densely packed nanofibrils, and isolated nanofibrils. With the varying solvent selectivity, the P3HT-b-PEO chains displayed a hybrid photophysical property depending on the competition between intrachain and interchain excitonic coupling, resulting in the transformation between J-and H-aggregation. Overall, this work offered an effective way to demonstrate the correlation and transformation between p-p stacking of P3HT and microphase separation, and how the conformation of P3HT chains influenced the photophysical properties of the copolymer during solvent blending.

Despite recent impressive advances in the synthesis of allinorganic perovskite CsPbX 3 (X = Cl, Br, and I) via facile solution-based approaches, it remains challenging to achieve well-defined morphologies of interest, particularly one-dimensional (1D) nanowires. Herein, we report a robust polar-solvent-assisted route to 1D CsPbBr 3 nanowires via room temperature supersaturated recrystallization. Notably, compared to CsPbBr 3 nanocubes synthesized in the absence of polar solvent acetonitrile (ACN), upon the introduction of a suitable amount of ACN into antisolvent toluene, CsPbBr 3 nanowires are rapidly yielded, experiencing a cubic-to-orthorhombic phase transformation and a blue-shifted emission. The formation mechanism of CsPbBr 3 nanowires can be qualitatively understood on the basis of the role of ACN as a structure-directing agent. Intriguingly, the addition of ACN renders an accelerated anion-exchange reaction between CsPbBr 3 and halide salts (i.e., Br-to-Cl and Br-to-I exchanges) due to improved dissolution of the halide ions in ACN. The polar solvent-directed growth strategy may represent an effective means of expanding the diversity of morphologies accessible to perovskite nanocrystals. As such, it facilitates an investigation into the dimensiondependent optical and optoelectronic properties of perovskite-based nanomaterials and devices. These CsPbBr 3 nanowires can be potentially used for nanoscale photonic, electronic, and optoelectronic devices, including photodetectors, light-emitting diodes, lasers, and solar cells.

Nanoribbon-shaped nanocomposites composed of conjugated polymer poly(3-hexylthiophene) (P3HT) nanoribbons and plasmonic gold nanorods (AuNRs) were crafted by a co-assembly of thiol-terminated P3HT (P3HT-SH) nanofibers with dodecanethiol-coated AuNRs (AuNRs-DDT). First, P3HT-SH nanofibers were formed due to interchain p-p stacking. Upon the addition of AuNRs-DDT, P3HT-SH nanofibers were transformed into nanoribbons decorated with the aligned AuNRs on the surface (i.e., nanoribbon-like P3HT/AuNRs nanocomposites). Depending on the surface coverage of the P3HT nanoribbons by AuNRs, these hierarchically assembled nanocomposites exhibited broadened and red-shifted absorption bands of AuNRs in nIR region due to the plasmon coupling of adjacent aligned AuNRs and displayed quenched photoluminescence of P3HT. Such conjugated polymer/plasmonic nanorod nanocomposites may find applications in fields, such as building blocks for complex superstructures, optical biosensors, and optoelectronic devices.