The research team from Zhengzhou university has developed a scalable, environmentally friendly method to produce chiral perovskite nanocrystal/ethyl cellulose (EC) chiral ink with exceptional stability and processability. This new ink overcomes long-standing challenges of traditional chiral perovskites, e.g., cumbersome synthesis, poor stability, and limited processability, while boasting exceptional substrate compatibility and patterning versatility. This new process enables the fabrication of flexible, high-performance circularly polarized luminescent films and patterns, opening new horizons in secure information encryption, 3D display, and wearable optoelectronic devices.
Circularly polarized luminescence (CPL) offers unique advantages in light field control, chiral optical activity, and spin-polarized coupling, making it essential for 3D displays, information encryption, and spintronics. Metal halide perovskite nanocrystals (NCs) are ideal for chiral light emission due to their tunable emission, high photoluminescence efficiency, and solution processability. However, the practical development of CPL-perovskite devices has been hindered by several limitations such as complex synthesis procedures requiring high temperatures and inert atmospheres, poor stability of the nanocrystals, and weak processability for patterning on diverse substrates.
Maintaining high CPL performance while improving environmental resistance and compatibility with fabrication processes remains a critical challenge. Furthermore, traditional petroleum-based polymer matrices are non-degradable and resource-intensive, conflicting with green development goals.
The solutions: The researchers reported a one-step wet-ball-milling method that produces up to 500 mL of chiral perovskite ink under ambient conditions—no inert gas protection, high temperatures, or complex solvents required. Chiral molecules (R-/S-DPEM) act as chiral initiators, endowing perovskite NCs with chirality through strong surface coupling (glum reaches 3.4×10-³). Ethyl cellulose (EC), a bio-based polymer, serves dual roles: it passivates perovskite NC surfaces via hydroxyl and ethoxy groups, boosting PL quantum yield from 56% to 83%; it also provides structural support, enhancing the ink's stability (retaining 80% brightness after 100 days of air storage) and processability, which can be processed into various patterns via screen printing, handwriting, soaking, or laser engraving—enabling the creation of QR codes, text, and complex shapes that maintain stable circularly polarized luminescence.
The future: Future research will focus on three key directions: developing novel chiral ligands to deepen the understanding of chirality transfer mechanisms; optimizing material performance to improve glum values and long-term stability for industrial demands; and exploring new scalable production processes to accelerate commercialization.
The impact: This study marks a significant leap forward in the scalable synthesis and practical application of chiral perovskite materials, and sets the stage for a technological application in display, anti-counterfeiting, and wearable electronic devices.
The research has been recently published in the online edition of Materials Futures, a prominent international journal in the field of interdisciplinary materials science research.
Reference: Boya Li, Leimeng Xu, Wenxuan Fan, Fangru Wang, Wanjie Wang, Jizhong Song. Scale-up synthesis of perovskite nanocrystal/cellulose chiral ink toward patterned and circularly polarized luminescence[J]. Materials Futures, 2026, 5(2): 025301. DOI: 10.1088/2752-5724/ae3592
