Mishra Leepsa, Behera Ranjan Kumar, Panigrahi Aradhana, Sarangi Manas Kumar
Department of Physics, Indian Institute of Technology Patna, Bihar, India, 801106.
J Phys Chem Lett. 2022 May 19;13(19):4357-4364. doi: 10.1021/acs.jpclett.2c00764. Epub 2022 May 11.
Regulated excited state energy and charge transfer play a pivotal role in nanoscale semiconductor device performance for efficient energy harvesting and optoelectronic applications. Herein, we report the influence of Förster resonance energy transfer (FRET) on the excited-state dynamics and charge transport properties of metal halide perovskite nanocrystals (PNCs), CsPbBr, and its anion-exchanged counterpart CsPbCl with CdSe/ZnS quantum dots (QDs). We report a drop in the FRET efficiency from ∼85% (CsPbBr) to ∼5% (CsPbCl) with QDs, inviting significant alteration in their charge transport properties. Using two-probe measurements we report substantial enhancement in the current for the blend structure of PNCs with QDs, originating from the reduced trap sites, compared to that of the pristine PNCs. The FRET-based upshot in the conduction mechanism with features of negative differential resistance and negligible hysteresis for CsPbBr PNCs can add new directions to high performance-based photovoltaics and optoelectronics.
受调控的激发态能量和电荷转移在用于高效能量收集和光电子应用的纳米级半导体器件性能中起着关键作用。在此，我们报告了Förster共振能量转移（FRET）对金属卤化物钙钛矿纳米晶体（PNCs）、CsPbBr及其与CdSe/ZnS量子点（QDs）进行阴离子交换后的对应物CsPbCl的激发态动力学和电荷传输性质的影响。我们报告了与量子点结合时FRET效率从约85%（CsPbBr）降至约5%（CsPbCl），这使其电荷传输性质发生了显著变化。通过双探针测量，我们报告了与原始PNCs相比，PNCs与量子点的混合结构的电流大幅增强，这源于陷阱位点的减少。基于FRET在CsPbBr PNCs传导机制中产生的具有负微分电阻和可忽略滞后特性的结果可为高性能光伏和光电子学增添新方向。
