Flexible Luminescent Solar Concentrators Using Photo-Stable, Heavy-Metal-Free Quantum Dots

• Main Authors: Yu-Fang Guo, 郭宇芳
• Other Authors: chi-tsu yuan
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/65598722890095339822

碩士 === 中原大學 === 物理研究所 === 104 === Luminescent solar concentrators (LSCs) can be used to concentrate both diffuse and direct components of sunlight without the need of complex light tracking, thus can facilitate solar cells to efficiently harvest solar energy, while reducing the material cost of solar cells. Unfortunately, organic materials exhibit large re-absorption losses due to small Stokes shift, narrow absorption bands and poor photo-stability, thus significantly limit their practical uses in LSCs.　Heavy-metal-containing colloidal quantum dots (CQDs) with Stokes-shift engineering hold some unique properties, such as low reabsorption losses, stable PL emission and high PL quantum yields that are much beneficial for achieving high-performance LSCs but those luminophores are strongly toxic and involve complex manufacturing processes.　Here, we demonstrate flexible, photo-stable and semi-transparent LSCs based on facile-microwave-synthesis, heavy-metal-free CuInS２/ZnS CQDs (CIS/ZnS QDs) embedded in the PDMS waveguide matrix. Such flexible PDMS matrix not only can serve as a host waveguide but also can well disperse CIS/ZnS QDs from aggregation-induced PL quenching.　By changing the cation ratio of CIS/ZnS QDs, the Stokes-shift and photoluminescence quantum yields (PL-QY) can be engineered. The PL emission of those QDs exhibit large Stoke-shift, broad emission and absorption bands, and long PL lifetime due to defect-related emission processes. To access the performance of our flexible LSCs, excitation-position-dependent PL measurement were used to quantify the re-absorption losses in the flexible LSCs.