Jianping Deng

Light conversion films represent one of the most pivotal functional materials in modern agriculture for enhancing crop photosynthetic efficiency. These films effectively transform inefficient solar spectral bands, such as ultraviolet and green light, into blue and red wavelengths that are readily absorbed by plants, thereby simultaneously increasing yield and improving quality. This review systematically summarizes recent advances in light converter agents incorporated into such films, with particular emphasis on rare‐earth complexes, organic small molecules, organic polymers, and emerging nanomaterials, along with their optical properties. Furthermore, the application performance of these films in the cultivation of fruits, vegetables, and ornamental flowers is comprehensively discussed, followed by a critical analysis of current technical bottlenecks and limitations. This work provides a systematic theoretical framework and cutting‐edge reference for advancing the fundamental understanding of light conversion materials, guiding technological innovations in light conversion films, and promoting the development of precision agriculture.

Luminescent materials have attracted significant attention owing to their diverse applications in flexible displays, bioimaging, information encryption, and chemical sensing. Polyurethanes (PUs), featuring high structural tailorability, dynamic hydrogen‐bonding networks, and microphase separation, serve not merely as passive host matrices but as active photophysical modulators. To overcome the abrupt transitions between disparate emitters, this review systematically categorizes functional fluorescent polyurethanes based on distinct matrix–emitter synergies across three primary luminescent sources: (1) metal‐based systems, where PU backbones act as macromolecular ligands to achieve dynamic coordination, high color purity, and extended lifetimes; (2) organic fluorophores and intrinsic emissive polyurethanes, where dense hydrogen‐bonding networks rigidify the microenvironment to suppress non‐radiative decay, enable stimuli‐responsive emission, and drive non‐traditional intrinsic luminescence (NTIL) via clusterization‐triggered emission (CTE); and (3) zero‐dimensional nanocomposites (e.g., quantum dots and perovskites), where PU serves as a protective micro‐encapsulant and surface defect passivator to enhance stability. Guided by an overarching conspectus scheme, we summarize structural design rules, combination modes, and energy‐transfer mechanisms governing PU–emitter interactions, while outlining critical challenges and future directions to inspire next‐generation smart optical polymers.

Cellulose‐based systems provide unique advantages for constructing circularly polarized luminescence (CPL) materials owing to their intrinsic chirality and clusteroluminescence properties. However, harnessing the clusteroluminescence of cellulose for the generation, modulation, and amplification of CPL remains challenging. The present work reports the first example of intrinsic CPL from cellulose derivatives by leveraging the synergistic effects of clusteroluminescence and the supramolecular chirality of the chiral nematic (cholesteric) liquid crystalline phase. Notably, the cholesteric cellulose derivatives can simultaneously transfer their inherent chirality and excitation energy to doped achiral fluorescent dyes, leading to amplified multicolor CPL emissions that extend into the near‐infrared region. By leveraging the selective reflection of cellulose derivative film, integration with achiral fluorescent and afterglow film enables tunable CPL, as well as circularly polarized afterglow. Moreover, multidimensional information encryption display and chiral logic system are successfully developed. This work offers valuable insights into the synergistic role of chirality and clusteroluminescence in biomacromolecules, and establishes a versatile and generalizable platform for constructing clusteroluminescence‐based CPL materials.

Cellulose‐based systems provide unique advantages for constructing circularly polarized luminescence (CPL) materials owing to their intrinsic chirality and clusteroluminescence properties. However, harnessing the clusteroluminescence of cellulose for the generation, modulation, and amplification of CPL remains challenging. The present work reports the first example of intrinsic CPL from cellulose derivatives by leveraging the synergistic effects of clusteroluminescence and the supramolecular chirality of the chiral nematic (cholesteric) liquid crystalline phase. Notably, the cholesteric cellulose derivatives can simultaneously transfer their inherent chirality and excitation energy to doped achiral fluorescent dyes, leading to amplified multicolor CPL emissions that extend into the near‐infrared region. By leveraging the selective reflection of cellulose derivative film, integration with achiral fluorescent and afterglow film enables tunable CPL, as well as circularly polarized afterglow. Moreover, multidimensional information encryption display and chiral logic system are successfully developed. This work offers valuable insights into the synergistic role of chirality and clusteroluminescence in biomacromolecules, and establishes a versatile and generalizable platform for constructing clusteroluminescence‐based CPL materials.

Luminescent materials are vital for diverse technological applications, such as light‐emitting diodes, medical diagnostics, and bio‐imaging, owing to their ability to convert energy into visible light. Traditional rare‐earth complexes face significant limitations, including resource scarcity, environmental toxicity, and aggregation‐caused quenching, that compromise efficiency in solid‐state devices, prompting a shift toward sustainable bio‐based polymers, with polylactic acid (PLA) emerging as a key candidate. This review addresses the urgent need for high‐performance, eco‐friendly alternatives by developing PLA‐based luminescent composites, which overcome previous challenges of toxicity, resource inefficiency, and quenching in conventional rare‐earth systems. Key outcomes demonstrate the successful integration of diverse dopants such as rare‐earth coordination complexes, boron compounds, inorganic phosphors, and perovskite derivatives into PLA matrices through physical doping and chemical bonding strategies, yielding enhanced optical properties including improved thermal stability, controlled room‐temperature phosphorescence, and resistance to quenching. These composites significantly advance photonic materials research by harmonizing superior functionalities like tunable emissions and chiral luminescence with the demands of environmental sustainability and resource efficiency. The incorporation of PLA's unique structural features, such as its inherent chirality and crystallinity, enables unprecedented control over molecular organization and excited‐state dynamics for applications in anti‐counterfeiting and sensors. Future research should focus on optimizing dopant‐polymer synergies to unlock potential in circularly polarized emission and expand the use of these composites in scalable green photonic technologies.