Photophysical properties of wavelength-tunable methylammonium lead halide perovskite nanocrystals. Issue 1 (2nd December 2016)

• Record Type: Journal Article
• Authors: Freppon, Daniel J.; Men, Long; Burkhow, Sadie J.; Petrich, Jacob W.; Vela, Javier; Smith, Emily A.
• Is Part Of: Journal of materials chemistry. Volume 5:Issue 1(2016)
• Page Start: 118
• Page End: 126
• Publication Date: 2016-12-02
• Subjects: Materials -- Periodicals; Chemistry, Analytic -- Periodicals; Optical materials -- Research -- Periodicals; Electronics -- Materials -- Research -- Periodicals; 543.0284
• DOI: 10.1039/c6tc03886g
• Languages: English
• ISSNs: 2050-7526

Abstract

Abstract : The single halide as well as the majority of the mixed halide nanocrystals do not show luminescence intermittency. Abstract : We present the time-correlated luminescence of isolated nanocrystals of five methylammonium lead mixed-halide perovskite compositions (CH3 NH3 PbBr3− x I x ) that were synthesized with varying iodide and bromide anion loading. All analyzed nanocrystals had a spherical morphology with diameters in the range of 2 to 32 nm. The luminescence maxima of CH3 NH3 PbBr3− x I x nanocrystals were tuned to wavelengths ranging between 498 and 740 nm by varying the halide loading. Both CH3 NH3 PbI3 and CH3 NH3 PbBr3 nanocrystals exhibited no luminescence intermittency for more than 90% of the 250 s analysis time, as defined by a luminescence intensity three standard deviations above the background. The mixed halide CH3 NH3 PbBr0.75 I0.25, CH3 NH3 PbBr0.50 I0.50, and CH3 NH3 PbBr0.25 I0.75 nanocrystals exhibited luminescence intermittency in 18%, 4% and 26% of the nanocrystals, respectively. Irrespective of luminescence intermittency, luminescence intensities were classified for each nanocrystal as: (a) constant, (b) multimodal, (c) photobrightening, and (d) photobleaching. Based on their photophysics, the CH3 NH3 PbBr3− x I x nanocrystals can be expected to be useful in a wide-range of applications where low and non-intermittent luminescence is desirable, for example as imaging probes and in films for energy conversion devices.