Stokes-Shift-Engineered Indium Phosphide Quantum Dots for Efficient Luminescent Solar Concentrators

Abstract

Luminescent solar concentrators (LSCs) show promise because of their potential for low-cost, large-area, and high-efficiency energy harvesting. Stokes shift engineering of luminescent quantum dots (QDs) is a favorable approach to suppress reabsorption losses in LSCs; however, the use of highly toxic heavy metals in QDs constitutes a serious concern for environmental sustainability. Here, we report LSCs based on cadmium-free InP/ZnO core/shell QDs with type-II band alignment that allow for the suppression of reabsorption by Stokes shift engineering. The spectral emission and absorption overlap was controlled by the growth of a ZnO shell on an InP core. At the same time, the ZnO layer also facilitates the photostability of the QDs within the host matrix. We analyzed the optical performance of indium-based LSCs and identified the optical efficiency as 1.45%. The transparency, flexibility, and cadmium-free content of the LSCs hold promise for solar window applications.

Triplex Glass Laminates with Silicon Quantum Dots for Luminescent Solar Concentrators

“…To improve the performance of an LSC, one of the most effective approaches is to enhance the PLQY of fluorophores. Most of the LSCs with decent optical efficiencies are based on QDs with PLQY above 50% [6c,6e,6f,20] . Surface functionalization of the hydride‐terminated Si QDs with organic ligands has made the synthesis of the stable colloidal Si QD solution with PLQY above 50% feasible.…”

“…Finally, we fabricated a medium‐size (9 × 9 × 0.3 cm 3 ), highly transparent (transmittance of ≈79% at 500 nm) LSC based on the optimized Si QDs/OSTE nanocomposite, with an optical power efficiency of 3.7%, as well as a thicker one (9 × 9 × 0.6 cm 3 , transmittance of ≈62% at 500 nm), featuring an efficiency of 7.9%. These values put Si QDs on par with other colloidal QDs, such as CuInS 2 , [6c] highlighting potential of this material system, where element abundance and nontoxicity are clear advantages.…”

“…This is due to their broadband absorption and unique size/composition‐dependent optical properties, such as structure‐engineered Stokes shift, a high photoluminescence quantum yield (PLQY), and desirable photo/chemical stability. [ 6 ] Recently, a CuInS 2 QD‐based LSC with dimensions of 30 × 30 × 0.7 cm 3 has achieved an optical efficiency of 6.8% (400–750 nm transmittance around 40%), which is promising for the large‐scale application of LSCs. [ 7 ] In addition, LSCs based on silicon QDs have drawn increasing interest in recent years.…”

“…This is an alternative structure for LSCs, which replicates some modern windows and features both for the protection of the active layer from the environment and for the enhancement of the unit mechanical strength. [ 10 ] Furthermore, the propagation losses can be reduced by laminating the nanocomposite between two sheets of optically clear glass, due to the shortened optical path within the QD layer [6c,11] …”

Effective Neural Photostimulation Using Indium-Based Type-II Quantum Dots

“…Zinc oxide (ZnO) has the potential to form a type-II band alignment by incorporation onto an InP core as we reported previously (see Figure 1a). 44 ZnO is a wide band gap semiconductor (3.37 eV 45 ), which has been used for gas sensors, varistors, generators of surface acoustic waves, and solar cells due to its optical, acoustic, and electric properties. 46−48 Advantageously, it has high radiation, chemical, and thermal resistance; 46 in addition, it shows higher biocompatibility compared to nonoxide materials and has been used for various biological applications.…”