Affiliation:
1. Department of Materials Science and Engineering National Tsing Hua University Hsinchu 300 Taiwan
2. Research Center for Applied Sciences Academia Sinica Taipei 115 Taiwan
3. Department of Physics National Taiwan University Taipei 106 Taiwan
4. Physikalisch‐Technische Bundesanstalt (PTB) Bundesallee 100 38116 Braunschweig Germany
5. Department of Chemical Engineering National Taiwan University Taipei 106 Taiwan
6. Graduate Institute of Electronics Engineering National Taiwan University Taipei 106 Taiwan
Abstract
AbstractOwing to their excellent carrier mobility, high absorption coefficient, exceptional quantum efficiency, and low‐cost solution processability, perovskite quantum dots (PQDs) are a promising candidate for photodetection. However, PQDs‐based photodetectors typically show poor optoelectronic performances, mainly limited by their weak light–matter interaction. In this work, MAPbBr3 PQDs are hybridized with graphene (Gr) and morphologically controlled plasmonic gold nanocrystals (AuNCs) to demonstrate a superior photodetector at 432 nm through a synergetic effect. The experimental results indicate that three shaped AuNCs (i.e., sphere, the octahedron (OD), and rhombic dodecahedron (RD)) all contribute to better photodetection behaviors due to surface trap state passivation and enhanced charge carrier densities with longer lifetime compared to that of pristine PQDs. In particular, the PQDs/RD‐AuNCs/Gr system demonstrates a record‐high responsivity of 2.7 × 105 A W−1, a detectivity of 4.9 × 1013 Jones, and external quantum efficiency (EQE) of 7.9 × 107% at 1.6 µW cm−2 illumination power density of 432 nm wavelength with a lowest applied voltage of 1.0 V for a gate‐free PQDs/AuNCs/Gr‐based photodetector. Furthermore, to the authors’ knowledge, this device shows the highest responsivity among the PQDs/AuNCs/Gr‐based electrostatic gate‐free lateral configuration photodetectors.
Subject
Atomic and Molecular Physics, and Optics,Electronic, Optical and Magnetic Materials