Structural characterization of the as-synthesized nanocrystals was performed using both transmission electron microscopy (Jeol JEM-2010) and the X-ray diffraction (XRD Bruker D8 Advance). The concentrations of perovskite nanocrystals in toluene solution were determined by the mass of lead, which were measured by the inductively coupled plasma optical emission spectrometry (ICP-OES Optima 8000; Perkin-Elmer).
1PA spectra of the perovskite nanocrystals in solution phase (toluene) were measured using a Shimadzu UV1800 Ultraviolet –Visible spectrophotometer. A Shimadzu RF-5301pc spectrofluorophotometer was employed to record the one-photon-excited PL spectra of the nanocrystals in toluene. Measurements of the absolute PLQYs of the perovskite nanocrystals were performed using an Ocean-optics USB4000 spectrometer with a BaSO4-coated integrating sphere excited by laser beam at 400 nm.
1PA spectra of the perovskite nanocrystals in solution phase (toluene) were measured using a Shimadzu UV1800 Ultraviolet –Visible spectrophotometer. A Shimadzu RF-5301pc spectrofluorophotometer was employed to record the one-photon-excited PL spectra of the nanocrystals in toluene. Measurements of the absolute PLQYs of the perovskite nanocrystals were performed using an Ocean-optics USB4000 spectrometer with a BaSO4-coated integrating sphere excited by laser beam at 400 nm.