Advances in the construction, optical characteristics, and applications of chiral carbon dots
Chirality is a fundamental property ubiquitous in nature, playing a pivotal role across physics, chemistry, biology, and materials science. With the advent of nanotechnology, chiral research has extended to the nanoscale, where chiral quantum dots have attracted attention due to high photoluminescence quantum yields and stability. However, conventional II–VI quantum dots often contain toxic heavy metals, exhibit poor water solubility and biocompatibility, and require complex preparation. Carbon dots (CDs), a novel class of carbon-based nanomaterials under 10 nm, offer low toxicity, straightforward synthesis, and excellent biocompatibility. Chiral carbon dots (Ch-CDs) combine the advantages of CDs with intrinsic chirality, endowing them with circularly polarized luminescence (CPL) and distinctive photophysical and chemical properties. This review systematically refines and summarizes construction strategies for Ch-CDs, including one-step synthesis, surface modification, and assembly methods. It comprehensively elaborates on recent advances in optical properties, focusing on tunable multicolor CPL, CPL enhancement, and triplet-state emission, addressing a gap in reviews on triplet-related chiral functionalities. The challenges and future perspectives for diversified applications are proposed. Ch-CDs have been extensively applied in photoelectric detection, optical devices, biomedicine, information anti-counterfeiting, and encryption. This review aims to summarize current achievements and stimulate further research, fostering rapid development in the Ch-CDs field.