Construction stable and highly bright photoluminescence of Ag and Mn codoped Zn-In-Se nanocrystals toward wLEDs application

Single-Phase Cu,Mn-Codoped ZnGaS/ZnS Quantum Dots for Full-Spectrum White-Light-Emitting Diodes

“…The average decay times recorded at 450 and 500 nm were 0.845 and 1.714 μs, which are consistent with the lifetimes of host and Cu dopant emissions (Table S2). ,,, Besides, the average decay time recorded at 580 nm was 4.209 ms, which corresponded with Mn d–d states. ,,, …”

“…Besides, the diffraction peaks of the Cu,Mn:ZnGaS QDs were located between those for zinc blende ZnS (JCPDS 05-0566) and tetragonal ZnGa 2 S 4 (JCPDS 40-1462), which could be attributed to the alloy structure of Cu,Mn:ZnGaS QDs. , No diffraction peaks of Mn and Cu were found, indicating that Mn and Cu doping did not cause phase transformation of the crystal structure. After ZnS shelling, the diffraction peaks shifted toward the ZnS phase, revealing the formation of a ZnS shell. , To further clarify the composition of the core and core/shell QDs, the XPS and high-resolution XPS spectra were recorded and are given in Figure b–e. The XPS peak at 19.8 eV could be assigned to Ga 3d, indicating the presence of Ga (Figure c) .…”

“…After ZnS shelling, the diffraction peaks shifted toward the ZnS phase, revealing the formation of a ZnS shell. 43,44 To further clarify the composition of the core and core/shell QDs, the XPS and high-resolution XPS spectra were recorded and are given in Figure 2b−e. The XPS peak at 19.8 eV could be assigned to Ga 3d, indicating the presence of Ga (Figure 2c).…”

“…21,40,47,48 Besides, the average decay time recorded at 580 nm was 4.209 ms, which corresponded with Mn d−d states. 24,26,43,49 As shown in Figure 3c, with an increase of the Zn/Ga molar ratio, the host emission showed an obvious blue shift. The Tauc plots (Figure S2) of the (Ahv) 2 − hv relationship (A = absorbance, h = Planck's constant, and v = light frequency) also indicated that the corresponding band gap gradually increases from 3.38 to 3.48 eV, which was due to the higher band gap of ZnS (3.49 eV) than Ga 2 S 3 (2.5 eV).…”

Structure and luminescence properties of single-component melilite Sr2MgSi2O7:Ce/Tb/Sm for n-UV wLEDs

“…Specifically, for mode (iii), there are three main ways to achieve white PL via the single-phase phosphor, (1) singly doping, i.e., Dy 3+ , 11 (2) host defect-induced, 12 and (3) codoping multiple RE and/or TM ions via ET (Scheme S2 †). 13,14 Generally, although the first mode is the simpler and much more straightforward way, spectral adjustment is difficult, and the luminous efficiency/intensity is usually low. Meanwhile, the disadvantage of mode (ii) is that it cannot be precisely regulated and is greatly affected by the environment, thus presenting low stability.…”