am8b10618_si_001.pdf (2.06 MB)
Greener Luminescent Solar Concentrators with High Loading Contents Based on in Situ Cross-Linked Carbon Nanodots for Enhancing Solar Energy Harvesting and Resisting Concentration-Induced Quenching
journal contribution
posted on 2018-09-11, 00:00 authored by Maria Jessabel Talite, Hsiu-Ying Huang, Yao-Hsuan Wu, Princess Genevieve Sena, Kun-Bin Cai, Tzu-Neng Lin, Ji-Lin Shen, Wu-Ching Chou, Chi-Tsu YuanA luminescent solar concentrator
(LSC) is composed of loaded luminophores and a waveguide that can
be employed to harvest and concentrate both direct and diffused sunlight
for promising applications in solar windows. Thus far, most of efficient
LSCs still relied on the heavy-metal-containing colloidal quantum
dots (CQDs) dispersed into a polymer matrix with a very low loading
(typically <1 wt %). Such low-loading constraint is required to
mitigate the concentration-induced quenching (CIQ) and maintain high
optical quality and film uniformity, but this would strongly reduce
the light-absorbing efficiency. To address all issues, greener LSCs
with high loading concentration were prepared by in situ cross-linking
organosilane-functionalized carbon nanodots (Si-CNDs), and their photophysical
properties relevant to LSC operation were studied. The PL emission
is stable and does not suffer from the severe CIQ effect for cross-linked
Si-CNDs even with 25 wt % loadings, thus exhibiting high solid-state
quantum yields (QYs) up to 45 ± 5% after the calibration of the
reabsorption losses. Furthermore, such LSCs can still hold high optical
quality and film uniformity, leading to low scattering losses and
high internal quantum efficiency of ∼22%. However, the reabsorption
losses need to be further addressed to realize large-area LSCs based
on earth-abundant, cost-effective CNDs.