Efficient and Flexible Luminescent Solar Concentrators Enabled by Vertically Aligned Doped Quantum Rods

ABSTRACT Flexible luminescent solar concentrators (LSCs) are attractive large‐area sunlight harvesters for wearable and portable photovoltaic devices. However, their optical performance is strongly limited by optical losses such as reabsorption and photon escape. In this work, we demonstrate high‐performance flexible LSCs based on vertically aligned tellurium‐doped CdSe/CdS/ZnS quantum rods (QRs) embedded in a polymer matrix. Tellurium doping (2%–4%) in CdSe/CdS/ZnS QRs introduces mid‐gap states, leading to a large Stokes shift (0.70 eV) that effectively suppresses reabsorption. Additionally, electric field‐assisted photopolymerization vertically aligns the QRs, dramatically enhancing total internal reflection and light confinement. Simulations confirm that vertical alignment maintains superior waveguiding efficiency under bending. By further integrating a backside aluminum reflector for photon recycling, the optimized LSC achieves a power conversion efficiency (PCE) of 2.22% and an optical efficiency of 17.50% under illumination (AM1.5G, 100 mW/cm 2 ). The device also exhibits exceptional mechanical flexibility, retaining over 90% of the initial efficiency after 100 bending cycles. This work provides a strategy for designing high‐efficiency, mechanically robust LSCs through synergistic electronic structure engineering, optical anisotropy control, and theoretical design guidance.