Construction of Laminated Luminescent Solar Concentrator “Smart” Window Based on Thermoresponsive Polymer and Carbon Quantum Dots

Abstract

Conventional luminescent solar concentrators (LSCs) lack the ability of dynamic modulation, energy saving, and privacy protection. In this work, a thermoresponsive laminated LSC was created and further used as a “smart” window (SW). The laminated LSC “smart” window (LSC-SW) was prepared by introducing carbon quantum dots (CQDs) into the sandwiched LSCs filled with aqueous thermosensitive polymer (PNIPAm) solution. To realize better compatibility, two types of fluorescent materials, hydrophilic CQDs (blue and green emitting CQDs), had been synthesized. The LSC-SW showed a good dynamic response to the ambient temperature and solar irradiation, which can be switched between transparent (<32 °C) and opaque states (>32 °C). Besides, the optimal LSC-SW had high transmittance (>80%) at the transparent state and low transmittance (<10%) at the opaque state. More importantly, the opaque state enabled the LSC-SW with higher external optical efficiency (ηopt of 7.49%), energy saving.