Sol-Gel Derived Strong Green Phosphor Zn2SiO4: Mn2+ and the Luminescent Properties

2014 ◽  
Vol 692 ◽  
pp. 304-310
Author(s):  
Yi Wang ◽  
Cheng Bin Huang ◽  
Pai Bin Xie ◽  
Song Ju Li ◽  
Zhi Wei Chen ◽  
...  
Keyword(s):  
Emission Spectrum ◽  
Doping Concentration ◽  
Annealing Temperature ◽  
Sol Gel ◽  
Green Emission ◽  
Luminescent Properties ◽  
Photoluminescence Properties ◽  
Green Phosphor ◽  
Strong Green Emission ◽  
Fluorescence Spectrometer

Being added by H3BO3 as flux, the nanosize strong green phosphor Zn2SiO4: Mn2+ was prepared by an improved sol-gel method. The structure and the morphology of the samples were examined by XRD, UV-VL spectrophotometer and SEM. The photoluminescence properties were measured by fluorescence spectrometer. Results show that, when the samples were annealed at 850°C for 2 hours, the intensity of emission spectrum of the sample is not strictly followed the monotonically increasing with the increase of Mn2+ doping concentration. It appears in a fluctuated tendency with the increase of doping concentration. In the 4% Mn2+ doping concentration and annealing temperature 950°C, the most strong green emission spectrum can be obtained. The mechanism of luminescence properties of this kind of material is analyzed.

Preparation of Y4MgSi3O13:Tb3+,Ce3+ Green Emitting Phosphor for White Light Emitting Diodes and its Luminescence Study

2011 ◽  
Vol 415-417 ◽  
pp. 1333-1339
Author(s):  
Guo Hua Song ◽  
Bin Jiang ◽  
Jian Wen Miao ◽  
Bang Dong Ding
Keyword(s):  
Sol Gel ◽  
Emission Spectra ◽  
Green Emission ◽  
Green Phosphor ◽  
Preparation Temperature ◽  
Light Emitting ◽  
Optimal Doping ◽  
Optimal Doping Concentration ◽  
White Light Emitting Diodes ◽  
Luminescence Characteristics

The Y4MgSi3O13:Tb3+,Ce3+green phosphors are synthesized by sol-gel method, the preparation temperature, reduction atmosphere and luminescence characteristics of Y4MgSi3O13doped with single Ce3+ions and Ce3+,Tb3+ions have been studied. The excitation and emission spectra of phosphors is determined by fluorescence spectrophotometer. The results show that: luminous intensity of Y4MgSi3O13:Tb3+phosphors increased after doped with Ce3+ions and the optimal doping concentration of Ce3+is 0.04. Y3.94MgSi3O13: 0.02Tb3+,0.04Ce3+green phosphor has the best luminescence characteristics under reduction atmosphere(H2:N2=1:3) at 1000°C, the phosphor gives intense green emission at 550nm originating from the5D4→7F5transition of Tb3+ions.

Photoluminescence Properties Influenced by Calcining Condition and Doping Concentration of Nano-Sized ZnGa2O4: Cr3+

2009 ◽  
Vol 610-613 ◽  
pp. 616-620 ◽  
Author(s):  
Wei Wei Zhang ◽  
Jun Ying Zhang ◽  
Hui Wan ◽  
Zi Yu Chen ◽  
Tian Min Wang
Keyword(s):  
Spinel Structure ◽  
Doping Concentration ◽  
Sol Gel ◽  
Blue Shift ◽  
Maximum Height ◽  
Photoluminescence Properties ◽  
Phosphor Powder ◽  
Red Emission ◽  
Intrinsic Excitation ◽  
Gel Technique

Chromium-activated ZnGa2O4 nano-sized phosphor powder was prepared by the Sol-Gel technique using citric acid as chelator, and the microstructure and luminescent property were studied. The host ZnGa2O4 belongs to the spinel structure and the ZnGa2O4:Cr3+ phosphor powder exhibited bright red emission band. The excitation bands with peak of maximum height at about 250 nm, 410 nm and 560 nm were related to the charge transfer (CT) of Ga-O, 4A2-4T1 and 4A2-4T2 transitions of Cr3+, respectively. Different quenching concentrations of the CT state and intrinsic excitation were discovered originating from different energy transfer schemes. Meanwhile, with the increasing of the calcining temperature the PLE spectrum exhibited an obvious blue-shift which is attributed to the enhancement of the crystal field.

scholarly journals Upconversion Luminescence and Photodegradation Performances of Pr Doped Y2SiO5Nanomaterials

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Yi Yang ◽  
Cheng Liu ◽  
Ping Mao ◽  
Lian-Jun Wang
Keyword(s):  
Doping Concentration ◽  
Crystal Size ◽  
Upconversion Luminescence ◽  
Sol Gel ◽  
Fine Crystal ◽  
X Ray ◽  
Photodegradation Rate ◽  
Infrared Spectrometer ◽  
Fluorescence Spectrometer ◽  
Degradation Time

Yttrium silicates Y2SiO5upconversion nanomaterials with different doping concentrations of praseodymium ion Pr are prepared by using a sol-gel method. X-ray diffractometer, SEM, Fourier transform infrared spectrometer, and fluorescence spectrometer have been employed to test the crystal structure and upconversion luminescence performances. The results indicate that samples calcined higher than 950°C present fine crystal structures, of which Si-O-Si band at 757–1048 cm−1splits into three fine peaks. The crystal size of the samples calcined at 950°C and 1000°C is 29.1 nm and 66.7 nm, respectively. The luminescence intensities of the samples are increasing at first and then decreasing, with the increasing of the doping concentrations of 0.47%, 0.77%, 0.96%, 2.95%, and 4.93%. Nanomaterial sample doped 0.96% Pr emits the highest upconversion luminescence intensity of 6.43 × 106 cps and shows the best photodegradation performance for nitrobenzene wastewater. It demonstrates that too much of Pr doping concentration would result in quenching of the fluorescence. Nevertheless, as the degradation time expands, sample doped 0.96% Pr shows much faster increasing of photodegradation rate than samples of other doping concentrations and reaches to a high photodegradation rate of 97.14% in 6 hours for 10 mg/L nitrobenzene wastewater.

scholarly journals Effects of Li+ Doping Concentration on Structure and Photoluminescence of the Y2O3: Ho3+/Yb3+ Up-conversion Film

2019 ◽  
pp. 1-8 ◽  
Author(s):  
Min Sun ◽  
Wenbo Hou ◽  
Juncheng Liu ◽  
Lifang Nie
Keyword(s):  
Doping Concentration ◽  
Crystal Size ◽  
Sol Gel ◽  
Emission Spectra ◽  
Luminescent Properties ◽  
Optical Transmittance ◽  
Li Doping ◽  
Maximum Value ◽  
Size Of Particles ◽  
Co Doped

The Li+ co-doped Y2O3: Ho3+/Yb3+ films were prepared with sol-gel method and spin-coating technique. The effects of Li+ on the structure and luminescent properties of the films were investigated. The results show the grain size increased first and then decreased with the increase of Li+ doping concentration. The crystal size of particles composing the film got the maximum value when Li+ concentration took 4 mol%. As Li+ doping concentration increased, the optical transmittance of the Y2O3: Ho3+/Yb3+ film improved at first then reduced and got the maximum at 3 mol%. Excited with a 980-nm laser, there were two green emissions in the up-conversion emission spectra, one centered at 535 nm, the other at 550 nm, which ascribed to the 5F4→5I8 and 5S2→5I8 transitions of Ho3+, respectively. The up-conversion luminescence intensity also increased firstly and then decreased with the Li+ doping concentration increase, and got the highest value at 2 mol%.

Red and Green Phosphors Glow on the Basis of Oxide Glass-Ceramics Doped with Eu3+ and Tb3+

2015 ◽  
Vol 670 ◽  
pp. 107-112 ◽  
Author(s):  
Seseg Yu. Tsyretarova ◽  
Nina M. Kozhevnikova ◽  
Nina S. Ereminа ◽  
Gennady M. Mokrousov
Keyword(s):  
Emission Spectrum ◽  
Glass Ceramic ◽  
Charge Transfer Band ◽  
Broad Band ◽  
Glass Ceramics ◽  
Green Emission ◽  
Luminescent Properties ◽  
Inorganic Materials ◽  
Oxide Glass ◽  
Excitation Spectra

Glass-ceramics phosphors were obtained by the introduction of the crystalline phase NaMg3Sc (MoO4)5:Eu3+,Tb3+ in the glass composition 8SiO2-20B2O3-5Lu2O3-31Bi2O3-36ZnO. The properties were characterized by X-ray diffraction (XRD), photoluminescence (PL) and photoluminescent excitation spectra (PLE). The XRD patterns were indicated NaMg3Sc (MoO4)5:Eu3+,Tb3+ crystallize well with the novel structure type and were assigned to the triclinic phase (space group PĪ, Z = 6). Glass-ceramic phosphors are well-known and promising as solid electrolytes, laser, luminescent and other inorganic materials. Luminescent properties of the phosphors are performed at room temperature. The excitation spectra of Eu-doped phosphor present strong absorption at 300 nm and the sharp peaks in the 350-500 nm range. Under the 394 nm excitation, intense red emission peak at 616 nm corresponding to 5D0→7F2 transition of Eu3+ is observed in the emission spectrum. The luminescence property indicates that the local symmetry of Eu3+ ion has no inversion center. The excitation spectra of Tb-doped phosphor by monitoring wavelength at 546 nm shows the intense broad band from 260 to 420 nm and the line at 234 nm, which is mainly attributed to charge-transfer band transition in MoO42- group, indicating the existence of energy transfer from MoO42- to Tb3+ in the Tb3+:glass-ceramic. The measured emission spectrum of Tb-doped phosphor has intense green emission at 546 nm corresponding to 5D4→7F5 transition of Tb3+, with λex=368 nm. The as-prepared phosphors may find potential applications in the field such as color displays, light-emitting diodes (LEDs) and optoelectronic devices.

Fabrication and Optical Properties of Mn Doped ZnS Nanowires

2011 ◽  
Vol 236-238 ◽  
pp. 2211-2215
Author(s):  
Jun Jie Qi ◽  
Qi Zhang ◽  
Qing Liang Liao ◽  
Zhan Qiang Deng ◽  
Yue Zhang
Keyword(s):  
Optical Properties ◽  
Aspect Ratio ◽  
Room Temperature ◽  
Green Emission ◽  
Deposition Method ◽  
Photoluminescence Properties ◽  
Room Temperature Photoluminescence ◽  
The Common ◽  
Strong Green Emission ◽  
Mn Doped

Mn doped ZnS nanowires with typical wurtzite single-crystalline structure were successfully synthesized via H2 assistant chemical evaporation deposition method. The investigations indicated that the diameter of Mn/ZnS Nanowire with high aspect ratio is 25~40nm, EDS results show that the content of Mn element is about 4.45at%. HRTEM and SAED results demonstrated that the Mn/ZnS nanowires grow along [101] direction, which was different from the common direction reported in literatures. Room temperature photoluminescence properties were also examined, showing a strong green emission centered at 523.04 nm, and a weak emission at 382.53 nm was also observed, showing a red shift of 45.53 nm comparing to the intrinsic luminescence.

Synthesis of Ba2SiO4:Eu2+ by a Hybrid Process and Its Luminescent Properties

2015 ◽  
Vol 15 (10) ◽  
pp. 8155-8160 ◽  
Author(s):  
Jung Hye Park ◽  
Wonsik Ahn ◽  
Young Jin Kim
Keyword(s):  
Colloidal Silica ◽  
Particle Distribution ◽  
Sol Gel ◽  
Green Emission ◽  
Luminescent Properties ◽  
Hybrid Process ◽  
Photoluminescence Spectra ◽  
Preparation Conditions ◽  
Gel Combustion ◽  
Silicon Sources

Ba2SiO4:Eu2+ powders were prepared using a sol–gel-combustion (hybrid) process with tetraethyl orthosilicate (TEOS) and colloidal silica (C-SiO2) as Si sources. The effects of the silicon sources and preparation conditions on phase formation and luminescent properties were investigated. The B2S:Eu2+ powders synthesized with TEOS were composed of the irregular particles, whereas C-SiO2 was more conducive to uniform particle distribution for the Ba2SiO4:Eu2+ powders, leading to the enhancement of the emission intensity. The photoluminescence spectra of the synthesized powders exhibited broad excitation bands spanning 250 to 450 nm, and strong green-emission bands, whose intensities and positions were heavily dependent on the concentration of Eu2+ and Sr2+ substituted for Ba2+ in Ba2SiO4.

scholarly journals High-pressure synthesis, crystal structure and photoluminescence properties of a new terbium silicate: Na2Tb1.08Ca2.92Si6O18H0.8

RSC Advances ◽  
2017 ◽  
Vol 7 (79) ◽  
pp. 50195-50199 ◽  
Author(s):  
Xinjian Bao ◽  
Xiaoyang Liu ◽  
Xi Liu
Keyword(s):  
Crystal Structure ◽  
High Pressure ◽  
Green Emission ◽  
Pressure Condition ◽  
Photoluminescence Properties ◽  
High Pressure Synthesis ◽  
Pressure Synthesis ◽  
Strong Green Emission

New terbium silicate Na2Tb1.08Ca2.92Si6O18H0.8 was synthesized at high pressure condition. The structure was and the photoluminescence properties were also investigated suggesting a strong green emission with the lifetime 2.498(7) ms.

Sign in / Sign up

Export Citation Format

Share Document