Emerging Trends in Liquid Luminescent Solar Concentrators: Progress and Prospects.

Liquid luminescent solar concentrators (liquid LSCs) have emerged as a promising alternative to conventional solid-state LSCs for enhancing solar energy harvesting. This review focuses primarily on the two major types of LSCs: liquid-based and thin-film-based systems. By comparing their respective advantages and limitations, it aims to identify how specific performance gaps, such as optical efficiency, quantum yield, scalability, recyclability, ease of fabrication, and cost can be addressed by one type over the other. Particular emphasis is placed on liquid LSCs, which, unlike their solid thin-film counterparts, offer unique benefits such as solution-processability, facile large-area coverage, self-healing potential, and material reusability. However, despite these benefits, research in this area remains scarce, with relatively few studies published to date. This review aims to provide a comprehensive overview of the recent developments in liquid LSCs, covering fundamental operating principles, key performance metrics, and major advances in luminescent materials, matrix design, and device architectures. Explored potential applications in sustainable energy systems are also reported. This review concludes by discussing ongoing challenges like stability, leakage, and contamination, and presenting future directions highlighting the promise of this underexplored field.