Spectral Heterogeneity of Hybrid Lead Halide Perovskites Demystified by Spatially Resolved Emission

Solution-processed films of methylammonium lead bromide (MAPbBr3) perovskites have remarkable photoluminescence (PL), with utility in light-emitting devices (LEDs) and photodiodes; however, the PL emission is often complex, heterogeneous, anomalous, or poorly understood. We provide a deeper understanding by studying PL spectra of single MAPbBr3 crystallites with intracrystallite spatial resolution. We uncover an emission emanating from the crystallite boundaries that is spectrally distinct from the band-to-band recombination-based emission from the crystallite interiors. Both forms of emission contribute to spatially averaged PL measured on heterogeneous samples. We also map the PL emission spectrum in a distant-dependent manner across a single crystallite. The systematic distance dependence observed reveals that a portion of the PL emission emanating from within a crystallite is waveguided and outcoupled from the boundaries of the crystallite in a form that is spectrally modulated by self-absorption. Spa...

[1]  K. S. Tikhonov,et al.  Extended carrier lifetimes and diffusion in hybrid perovskites revealed by Hall effect and photoconductivity measurements , 2016, Nature Communications.

[2]  T. Ohta,et al.  PbS Cubes with Pyramidal Pits: An Example of Etching Growth , 2009 .

[3]  Fuzhi Huang,et al.  Wavelength-tunable waveguides based on polycrystalline organic-inorganic perovskite microwires. , 2016, Nanoscale.

[4]  Song Jin,et al.  Lead halide perovskite nanowire lasers with low lasing thresholds and high quality factors. , 2015, Nature materials.

[5]  Yuxi Tian,et al.  Artifacts in Absorption Measurements of Organometal Halide Perovskite Materials: What Are the Real Spectra? , 2015, The journal of physical chemistry letters.

[6]  J. Luther,et al.  Low surface recombination velocity in solution-grown CH3NH3PbBr3 perovskite single crystal , 2015, Nature Communications.

[7]  Qidai Chen,et al.  The Role of Trap-assisted Recombination in Luminescent Properties of Organometal Halide CH3NH3PbBr3 Perovskite Films and Quantum Dots , 2016, Scientific Reports.

[8]  M. Grätzel,et al.  Sequential deposition as a route to high-performance perovskite-sensitized solar cells , 2013, Nature.

[9]  V. Sundström,et al.  Enhanced Organo-Metal Halide Perovskite Photoluminescence from Nanosized Defect-Free Crystallites and Emitting Sites. , 2015, The journal of physical chemistry letters.

[10]  D. Ginger,et al.  Anticorrelation between Local Photoluminescence and Photocurrent Suggests Variability in Contact to Active Layer in Perovskite Solar Cells. , 2016, ACS nano.

[11]  P. Parilla,et al.  Electronic Structure and Optical Properties of α-CH3NH3PbBr3 Perovskite Single Crystal. , 2015, The journal of physical chemistry letters.

[12]  Tsutomu Miyasaka,et al.  Organometal halide perovskites as visible-light sensitizers for photovoltaic cells. , 2009, Journal of the American Chemical Society.

[13]  Libai Huang,et al.  Spatial and temporal imaging of long-range charge transport in perovskite thin films by ultrafast microscopy , 2015, Nature Communications.

[14]  R. Camacho,et al.  Exploring the Electronic Band Structure of Organometal Halide Perovskite via Photoluminescence Anisotropy of Individual Nanocrystals. , 2016, Nano letters.

[15]  Yu Hou,et al.  Direct insight into crystallization and stability of hybrid perovskite CH3NH3PbI3via solvothermal synthesis , 2015 .

[16]  Chang-Lyoul Lee,et al.  Multicolored Organic/Inorganic Hybrid Perovskite Light‐Emitting Diodes , 2015, Advanced materials.

[17]  F. Bretenaker,et al.  Impact of Reabsorption on the Emission Spectra and Recombination Dynamics of Hybrid Perovskite Single Crystals. , 2017, The journal of physical chemistry letters.

[18]  Richard H. Friend,et al.  Photon recycling in lead iodide perovskite solar cells , 2016, Science.

[19]  M. Johnston,et al.  Formamidinium lead trihalide: a broadly tunable perovskite for efficient planar heterojunction solar cells , 2014 .

[20]  Dong Shi,et al.  Two-Photon Absorption in Organometallic Bromide Perovskites. , 2015, ACS nano.

[21]  A. Petrozza,et al.  Research Update: Luminescence in lead halide perovskites , 2016 .

[22]  Chunxiang Xu,et al.  Comparative investigation on temperature-dependent photoluminescence of CH3NH3PbBr3 and CH(NH2)2PbBr3 microstructures , 2016 .

[23]  Alain Goriely,et al.  High-quality bulk hybrid perovskite single crystals within minutes by inverse temperature crystallization , 2015, Nature Communications.

[24]  Tien Khee Ng,et al.  The recombination mechanisms leading to amplified spontaneous emission at the true-green wavelength in CH3NH3PbBr3 perovskites , 2015 .

[25]  R. Schropp,et al.  Carrier Diffusion Lengths in Hybrid Perovskites: Processing, Composition, Aging, and Surface Passivation Effects , 2016 .

[26]  Tze Chien Sum,et al.  Room-temperature near-infrared high-Q perovskite whispering-gallery planar nanolasers. , 2014, Nano letters.

[27]  Q. Xiong,et al.  Tailoring the lasing modes in semiconductor nanowire cavities using intrinsic self-absorption. , 2013, Nano letters.

[28]  Chang-ling Zou,et al.  Output Coupling of Perovskite Lasers from Embedded Nanoscale Plasmonic Waveguides. , 2016, Journal of the American Chemical Society.

[29]  Wei Zhang,et al.  Enhanced optoelectronic quality of perovskite thin films with hypophosphorous acid for planar heterojunction solar cells , 2015, Nature Communications.

[30]  Jinsong Huang,et al.  Quantification of re-absorption and re-emission processes to determine photon recycling efficiency in perovskite single crystals , 2017, Nature Communications.

[31]  Tien Khee Ng,et al.  Optical constants of CH3NH3PbBr3 perovskite thin films measured by spectroscopic ellipsometry. , 2016, Optics express.

[32]  C. Brabec,et al.  Detection of X-ray photons by solution-processed lead halide perovskites , 2015, Nature Photonics.

[33]  David T. Limmer,et al.  Origin of Reversible Photoinduced Phase Separation in Hybrid Perovskites. , 2016, Nano letters.

[34]  Yang Yang,et al.  Solution-processed hybrid perovskite photodetectors with high detectivity , 2014, Nature Communications.

[35]  Yang Yang,et al.  Interface engineering of highly efficient perovskite solar cells , 2014, Science.

[36]  G. Ran,et al.  Effect of excess PbBr2 on photoluminescence spectra of CH3NH3PbBr3 perovskite particles at room temperature , 2016 .

[37]  E. Sargent,et al.  Low trap-state density and long carrier diffusion in organolead trihalide perovskite single crystals , 2015, Science.