The second near-infrared (NIR-II, 1000–1700 nm) circularly polarized light holds significant untapped potential in areas such as optical anti-counterfeiting and information encryption due to its deeply covert nature. However, the typically low luminescence dissymmetry factor (g_lum) of circularly polarized luminescence (CPL) materials, particularly in NIR CPL materials, limits their practical application. Addressing this challenge, it is crucial to develop NIR CPL materials with enhanced g_lum. In this study, we present a series of chiral photonic micro-particles (CPMPs) with tunable chiral photonic bandgaps in the NIR-II range, capable of modulating NIR-II luminescent quantum dots to produce NIR CPL. These CPMPs not only impart chirality to the quantum dots, but also act as carriers, minimizing luminescence quenching from external environments. The tunable chiral photonic bandgap in CPMPs enables the generation of NIR CPL with a high |g_lum| value of up to 0.81, facilitating the advanced application in covert optical anti-counterfeiting. This work offers a straightforward and viable strategy for the development of NIR CPL materials, broadening their use in invisible information encryption and optical anti-counterfeiting technologies.

The generation of chirality in supramolecular structures from achiral building blocks has remained a challenge for a long time. In this study, we present a vortex-assisted chiral supramolecular polymerization from a series of achiral C₃-symmetric monomers, where the mechanism of symmetry-breaking is systematically investigated. By increasing the supersaturation, at the early stage of nucleation and growth, highly ordered assemblies can be generated as the initial chiral nuclei. Meanwhile, chiral assemblies from high supersaturation are hard to interwind into clusters, where clusters as nuclei are not conducive to being fractured by sheer force of vortex fluid. Therefore, it is concluded that chiral assemblies in the nucleation stage possess low energy barrier, so that chiral nuclei could be fractured and replicated by the vortex. By enlarging the initial chiral bias, the major chiral nuclei can evolute into the final chiral polymers.

Achieving large luminescence dissymmetry factors (g_lum) is challenging in the research field of circularly polarized luminescence (CPL). While various approaches have been developed to construct organic systems with CPL activity, there is still a lack of effective methods for fabricating CPL active inorganic materials. Herein, we propose an approach for endowing upconversion nanoparticles (UCNPs) and perovskite nanocrystal (PKNC) hybrid nanomaterials with upconverted circularly polarized luminescence (UC-CPL) activity. Chiral cesium lead bromides (CsPbBr₃) PKNCs were synthesized by a chiral-ligand-assistant method. Meanwhile, UCNP could be embedded into the chiral PKNC, enabling a photon upconvesion feature to the PKNC. The embedded UCNPs in PKNCs were confirmed by electron tomography. Consequently, various CPL activities, including prompt CPL, UC-CPL, and energy transfer enhanced circularly polarized luminescence (ET-CPL), were realized. The chiral perovskite nanocrystals could reabsorb the chiral energy generated from UCNPs, showing energy transfer enhanced CPL activity with four times magnification of the circular polarization. These findings provide a meaningful strategy for designing chiral photon upconversion inorganic nanomaterials with highly efficient UC-CPL activity.