A series of single phase,warm white light emitting phosphors,Gd(P_(x)V_(1−x))O_(4):y at%Sm^(3+),with 1 at%Bi^(3+) doping concentration were synthesized by high temperature solid state method in this work.The experimen...A series of single phase,warm white light emitting phosphors,Gd(P_(x)V_(1−x))O_(4):y at%Sm^(3+),with 1 at%Bi^(3+) doping concentration were synthesized by high temperature solid state method in this work.The experimental results indicate broadband cyan emission of Bi^(3+)and characteristic orange-red emission of Sm^(3+)can be effectively tuned by changing the ratios of PO^(3−)_(4)/VO^(3−)_(4) in Gd(P_(x)V_(1−x))O_(4):1 at%Sm^(3+),1 at%Bi^(3+),and the energy transfer process among VO^(3−)_(4),Sm^(3+),Bi^(3+) also can be adjusted.Based on this,warm white light emitting can be realized by further optimizing the doping concentration of Sm^(3+) in the phosphors.At 423 K,the PL intensity of Gd(P_(0.7)V_(0.3))O_(4):2 at%Sm^(3+),1 at%Bi^(3+) remains~84.3%of the initial value at 293 K,while the measured quantum efficiency is 67.8%.EL spectrum analysis results of the fabricated white light emitting diode(wLED)based on a 310 nm UV-chip and Gd(P_(0.7)V_(0.3))O4:2 at%Sm^(3+),1 at%Bi^(3+)phosphors imply low correlated color temperature(3132 K)and appropriate color-rending index(R_(a)=82.7).These results demonstrate that Gd(P_(0.7)V_(0.3))O4:2 at%Sm^(3+),1 at%Bi^(3+)is a good candidate for manufacturing UV-activated warm white light emitting diodes.展开更多
FTIR absorption spectra indicate that H^+can easily enter the crystal structure and form OH^-centers in Er:Yb:YCOB and O-H bonds prefer to lie in the a-c plane.Within our current studied concentration level,crystal sa...FTIR absorption spectra indicate that H^+can easily enter the crystal structure and form OH^-centers in Er:Yb:YCOB and O-H bonds prefer to lie in the a-c plane.Within our current studied concentration level,crystal samples with higher OH-abso rption coefficie nts demonstrate stro nger fluo rescence intensity and longer fluorescence lifetime at 1535 nm.As the stretching vibration energy of OH-group approximately corresponds to the energy gap between the 4 I11/2 and 4 I13/2 levels of Er^3+,and thus,OH^-ions can shorten the fluorescence lifetime of Er^3+-4I11/2 level by the phonon-assisted cross-relaxation process between the Er^3+and OH-ions.Our curre nt results confirm that a certain conte nt of OH ions can enhance the ene rgy transfer process from Yb^3+to Er^3+and subsequently promote fluorescence output in 1.5-1.6μm.展开更多
A comprehensive investigation is carried out to compare the spectroscopic properties, absorption saturation behaviors and lasing properties of a Yb ion in tetragonal LuPO4 and LuVO4 isomorphic crystals. Significant di...A comprehensive investigation is carried out to compare the spectroscopic properties, absorption saturation behaviors and lasing properties of a Yb ion in tetragonal LuPO4 and LuVO4 isomorphic crystals. Significant distinctions are revealed in many aspects of the lasing behavior for the Yb ion doped in the two crystal hosts, and Yb：LuPO_4 proves to be superior to Yb：LuVO4 since it enables efficient laser action to be much more easily achieved. With a 0.6 mm thick crystal plate of Yb：LuPO4, an output power of 3.30 W can be generated with an optical–optical conversion efficiency of 50.8%; whereas with a 2 mm long miniature crystal rod, the output power produced can reach 8.35 W with an optical–optical conversion efficiency of 46.7%.展开更多
Dual-functional NiCo2S4 polyhedral architectures with outstanding electrochemical performance for supercapacitors and lithium-ion batteries(LIBs) have been rationally designed and successfully synthesized by a hydroth...Dual-functional NiCo2S4 polyhedral architectures with outstanding electrochemical performance for supercapacitors and lithium-ion batteries(LIBs) have been rationally designed and successfully synthesized by a hydrothermal method. The as-synthesized NiCo2S4 electrode for supercapacitor exhibits an outstanding specific capacitance of 1298 Fg-1 at 1 A g-1 and an excellent rate capability of ~80.4% at20 A g-1. Besides, capacitance retention of 90.44% is realized after 8000 cycles. In addition, the NiCo2S4 as anode in LIBs delivers high initial charge/discharge capacities of 807.6 and 972.8 m Ah g-1 at 0.5 C as well as good rate capability. In view of these points, this work provides a feasible pathway for assembling electrodes and devices with excellent electrochemical properties in the next generation energy storage applications.展开更多
A new organic crystal of 4-N, N-dimethylamino-4＇-N＇-methyl-stilbazolium benzene sulfonate （DASBS） was synthesized and characterized for the first time. It is a derivative of 4-N, N-dimethylamino-4＇-N＇-methyl-sti...A new organic crystal of 4-N, N-dimethylamino-4＇-N＇-methyl-stilbazolium benzene sulfonate （DASBS） was synthesized and characterized for the first time. It is a derivative of 4-N, N-dimethylamino-4＇-N＇-methyl-stilbazolium tosylate （DAST） with the benzene sulfonate replacing p-toluenesulfonate. Single crystal XRD demonstrated that the crystal structure of DASBS. H20 was triclinic. The thermal analysis of this new crystal was also conducted, and the melting point was obtained to be 232℃.展开更多
1.Text In recent years,new organic second-order nonlinear optical materials have been widely used in optical imaging,data storage,information processing and communication,etc.[1].Therefore,designing and growing crysta...1.Text In recent years,new organic second-order nonlinear optical materials have been widely used in optical imaging,data storage,information processing and communication,etc.[1].Therefore,designing and growing crystalline materials with strong second-order nonlinear effects is one of the current research hotspots[2].展开更多
基金Project supported by the National Natural Science Foundation of China(51972181,61705231)Major Basic Research Projects of Shandong Natural Science Foundation(ZR2018ZB0650)+2 种基金China Postdoctoral Science Foundation(2015M580573)High Quality Course Construction Project of Graduate Education in Shandong Province(SDYKC18051)Postgraduate Tutor Ability Improvement Project of Shandong Province(SDYY17179)。
文摘A series of single phase,warm white light emitting phosphors,Gd(P_(x)V_(1−x))O_(4):y at%Sm^(3+),with 1 at%Bi^(3+) doping concentration were synthesized by high temperature solid state method in this work.The experimental results indicate broadband cyan emission of Bi^(3+)and characteristic orange-red emission of Sm^(3+)can be effectively tuned by changing the ratios of PO^(3−)_(4)/VO^(3−)_(4) in Gd(P_(x)V_(1−x))O_(4):1 at%Sm^(3+),1 at%Bi^(3+),and the energy transfer process among VO^(3−)_(4),Sm^(3+),Bi^(3+) also can be adjusted.Based on this,warm white light emitting can be realized by further optimizing the doping concentration of Sm^(3+) in the phosphors.At 423 K,the PL intensity of Gd(P_(0.7)V_(0.3))O_(4):2 at%Sm^(3+),1 at%Bi^(3+) remains~84.3%of the initial value at 293 K,while the measured quantum efficiency is 67.8%.EL spectrum analysis results of the fabricated white light emitting diode(wLED)based on a 310 nm UV-chip and Gd(P_(0.7)V_(0.3))O4:2 at%Sm^(3+),1 at%Bi^(3+)phosphors imply low correlated color temperature(3132 K)and appropriate color-rending index(R_(a)=82.7).These results demonstrate that Gd(P_(0.7)V_(0.3))O4:2 at%Sm^(3+),1 at%Bi^(3+)is a good candidate for manufacturing UV-activated warm white light emitting diodes.
基金Project supported by the National Natural Science Foundation of China(11204148,11374170)Major Basic Research Projects of Shandong Natural Science Foundation(ZR2018ZB0650)+4 种基金China Postdoctoral Science Foundation(2015M580573)the Applied Basic Research Programs for Youths of Qingdao(15-9-1-52-JCH)Taishan Scholar Program of Shandong Provincethe Qingdao Postdoctoral Application Research Project(2015127)the Open Projects of State Key Laboratory of Rare-earth Resource Utilization(RERU2016015)
文摘FTIR absorption spectra indicate that H^+can easily enter the crystal structure and form OH^-centers in Er:Yb:YCOB and O-H bonds prefer to lie in the a-c plane.Within our current studied concentration level,crystal samples with higher OH-abso rption coefficie nts demonstrate stro nger fluo rescence intensity and longer fluorescence lifetime at 1535 nm.As the stretching vibration energy of OH-group approximately corresponds to the energy gap between the 4 I11/2 and 4 I13/2 levels of Er^3+,and thus,OH^-ions can shorten the fluorescence lifetime of Er^3+-4I11/2 level by the phonon-assisted cross-relaxation process between the Er^3+and OH-ions.Our curre nt results confirm that a certain conte nt of OH ions can enhance the ene rgy transfer process from Yb^3+to Er^3+and subsequently promote fluorescence output in 1.5-1.6μm.
基金Project supported by the National Natural Science Foundation of China(Grant No.11574170)
文摘A comprehensive investigation is carried out to compare the spectroscopic properties, absorption saturation behaviors and lasing properties of a Yb ion in tetragonal LuPO4 and LuVO4 isomorphic crystals. Significant distinctions are revealed in many aspects of the lasing behavior for the Yb ion doped in the two crystal hosts, and Yb：LuPO_4 proves to be superior to Yb：LuVO4 since it enables efficient laser action to be much more easily achieved. With a 0.6 mm thick crystal plate of Yb：LuPO4, an output power of 3.30 W can be generated with an optical–optical conversion efficiency of 50.8%; whereas with a 2 mm long miniature crystal rod, the output power produced can reach 8.35 W with an optical–optical conversion efficiency of 46.7%.
基金the National Natural Science Foundation of China(51672109)the Natural Science Foundation of Shandong Province for Excellent Young Scholars(ZR2016JL015).
文摘Dual-functional NiCo2S4 polyhedral architectures with outstanding electrochemical performance for supercapacitors and lithium-ion batteries(LIBs) have been rationally designed and successfully synthesized by a hydrothermal method. The as-synthesized NiCo2S4 electrode for supercapacitor exhibits an outstanding specific capacitance of 1298 Fg-1 at 1 A g-1 and an excellent rate capability of ~80.4% at20 A g-1. Besides, capacitance retention of 90.44% is realized after 8000 cycles. In addition, the NiCo2S4 as anode in LIBs delivers high initial charge/discharge capacities of 807.6 and 972.8 m Ah g-1 at 0.5 C as well as good rate capability. In view of these points, this work provides a feasible pathway for assembling electrodes and devices with excellent electrochemical properties in the next generation energy storage applications.
文摘A new organic crystal of 4-N, N-dimethylamino-4＇-N＇-methyl-stilbazolium benzene sulfonate （DASBS） was synthesized and characterized for the first time. It is a derivative of 4-N, N-dimethylamino-4＇-N＇-methyl-stilbazolium tosylate （DAST） with the benzene sulfonate replacing p-toluenesulfonate. Single crystal XRD demonstrated that the crystal structure of DASBS. H20 was triclinic. The thermal analysis of this new crystal was also conducted, and the melting point was obtained to be 232℃.
基金supported by the Key Projects of the Joint Fund for Regional Innovation and Development of the National Natural Science Foundation of China(No.U22A20123)Program for National Natural Science Foundation of China(No.51972181)the program for Natural Science Foundation of Shandong Province(No.ZR2020ME022).
文摘1.Text In recent years,new organic second-order nonlinear optical materials have been widely used in optical imaging,data storage,information processing and communication,etc.[1].Therefore,designing and growing crystalline materials with strong second-order nonlinear effects is one of the current research hotspots[2].
