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Noble metal nanostructures with plasmonic circular dichroism (PCD) have attracted interest, and a modulation of PCD is of great importance for their potential applications. Herein, we propose a supramolecular strategy for achieving dual thermal and photoswitchable PCD. When guanosine (G), deoxyguanosine (dG), and boric acid modified achiral gold nanorods (GNRs) were coassembled into a hydrogel, hybrid nanofibers with PCD were produced. When the hydrogel was heated, the nanofiber was disassembled and the PCD disappeared. As the hydrogel was thermally reversible, a thermo-controlled PCD could be realized. The hybrid hydrogel also showed photoswitchable PCD. When the gel was irradiated with an IR laser, the PCD disappeared. It can be restored by being placed at room temperature. Moreover, the hybrid gel was selectively responsive to the circularly polarized light (CPL). For (G/dG)-GNR hybrid assemblies, the R-CPL irradiation showed photothermal efficiency higher than that of L-CPL, which made it useful for an IR-irradiation-controlled release of drug molecules.

Biomaterials in nature often exhibit hierarchical chiral structures with an intriguing mechanism involving hierarchical chirality transfer from molecular to supramolecular and the nano- or microscale level. To mimic the cross-level chirality transfer, we present here one kind of host–guest complex system built of β-cyclodextrin (β-CD), sodium dodecyl sulfate (SDS), and fluorescent dyes, which show multilevel chirality, including molecular chirality of β-CD, induced supramolecular chirality of β-CD/SDS host–guest complexes, a chiral lattice self-assembled nanosheet, mesoscopic chirality of an assembled helical tube, induced chirality of a dye-doped chiral tube. The hierarchical chirality involved a chiral lattice self-assembly process, which can be identified by small-angle X-ray scattering, optical studies, circular dichroism, and circularly polarized luminescence spectral measurements. Benefiting from the chiral lattice self-assembly, intense circularly polarized luminescence was observed from the achiral dye-doped complexes with a large dissymmetry factor up to +0.1. This work thus provides a feasible insight for developing hierarchical chiroptical materials based on the lattice self-assembly.

Directed self-assembly has been used to create micro-nano scale patterns, including chiral periodic structures of organic molecules, for potential applications in optics, photonics, metamaterials, and medical and sensing technologies. This study presents a straightforward approach for fabricating large-scale chiral grating porphyrin assemblies through template-assisted techniques. The solution of tetrakis(4-sulfonatophenyl) porphyrin (TPPS) was induced by chiral amino acids (L/D-arginine and L/D -serine) to self-assemble into highly ordered chiral grating structures with the assistance of sodium dodecyl sulfate (SDS). The structures show precise line widths (5.5 μm) and gaps (18 μm). Using in situoptical microscopy and second harmonic generation (SHG) microscopy, the chiral characteristics and dynamic evolution of the template-assisted self-assembly are investigated. It is found that the chirality of amino acids induced TPPS self-assembled into chiral structures and the liquid contraction interface significantly enhanced the chirality of the assemblies. This study is significant for understanding the mechanism of chiral evolution and designing novel micro-nano materials with predetermined chiral properties.

Triplet-triplet annihilation based photon upconversion (TTA-UC) were constructed successfully by chiral self-assembly strategy. Enhanced TTA-UC could be obtained in the racemic assemblies compared with the homochiral assemblies.