Lu3Al5O12(LuAG) thin films with different Tb^3+ concentration were prepared on carefully cleaned (111 ) silicon wafer by a Peehini process and dip-coating technique. Heat treatment was performed in the temperatur...Lu3Al5O12(LuAG) thin films with different Tb^3+ concentration were prepared on carefully cleaned (111 ) silicon wafer by a Peehini process and dip-coating technique. Heat treatment was performed in the temperature range from 800 to 1100 ℃. The crystal structure was analyzed by XRD. The results show that LuAG film starts to crystallize at about 900 ℃, and the particle size increases with the sintering temperature. Excitation and emission spectra of Tb^3+ doped LuAG films were measured. The effects of heat-treatment temperature and doping concentration of Th3 + on the luminescent properties were also investigated. For a comparison study, Th^3+-doped LuAG powders were also prepared by the same sol-gel method.展开更多
The performance of pearlescent pigment significantly affected by the grain size and the roughness of deposited film. The effect of TiCl_(4) concentration on the initial deposition of TiO_(2) on mica by atmospheric pre...The performance of pearlescent pigment significantly affected by the grain size and the roughness of deposited film. The effect of TiCl_(4) concentration on the initial deposition of TiO_(2) on mica by atmospheric pressure chemical vapor deposition(APCVD) was investigated. The precursor concentration significantly affected the deposition and morphology of TiO_(2) grains assembling the film. The deposition time for fully covering the surface of mica decreased from 120 to 10 s as the TiCl_(4) concentration increased from 0.38%to 2.44%. The grain size increased with the TiCl_(4) concentration. The AFM and TEM analysis demonstrated that the aggregation of TiO_(2) clusters at the initial stage finally result to the agglomeration of fine TiO_(2) grains at high TiCl_(4) concentrations. Following the results, it was suggested that the nucleation density and size was easy to be adjusted when the TiCl_(4) concentration is below 0.90%.展开更多
As a promising solid electrolyte for thin-film lithium batteries,the amorphous Li_(0.33)La_(0.56)TiO_(3)(LLTO)thin film has gained great interest.However,enhancing ionic conductivity remains challenging in the field.H...As a promising solid electrolyte for thin-film lithium batteries,the amorphous Li_(0.33)La_(0.56)TiO_(3)(LLTO)thin film has gained great interest.However,enhancing ionic conductivity remains challenging in the field.Here,a systematical study was performed to improve the ionic conductivity of sputter-deposited LLTO thin films via the optimization of processing atmosphere and temperature.By combining the optimized oxygen partial pressure(30%),annealing temperature(300℃),and annealing atmosphere(air),an amorphous LLTO thin film with an ionic conductivity of 5.32910^(-5)·S·cm^(-1) at room temperature and activation energy of 0.26 eV was achieved.The results showed that,first,the oxygen partial pressure should be high enough to compensate for the oxygen loss,but low enough to avoid the abusive oxygen scattering effect on lithium precursors that results in a lithium-poor composition.The oxygen partial pressure needs to achieve a balance between lithium loss and oxygen defects to improve the ionic conductivity.Second,a proper annealing temperature reduces the oxygen defects of LLTO thin films while maintaining its amorphous state,which improves the ionic conductivity.Third,the highest ionic conductivity for the LLTO thin films that were annealed in air(a static space without a gas stream)occurs because of the decreased lithium loss and oxygen defects during annealing.These findings show that the lithium-ion concentration and oxygen defects affect the ionic conductivity for amorphous LLTO thin films,which provides insight into the optimization of LLTO thin-film solid electrolytes,and generates new opportunities for their application in thinfilm lithium batteries.展开更多
基金Project supported by the National High Technology Research and Development Programof China(863 Program) (2002 AA324070) and the National Natural Science Foundation of China (50332050)
文摘Lu3Al5O12(LuAG) thin films with different Tb^3+ concentration were prepared on carefully cleaned (111 ) silicon wafer by a Peehini process and dip-coating technique. Heat treatment was performed in the temperature range from 800 to 1100 ℃. The crystal structure was analyzed by XRD. The results show that LuAG film starts to crystallize at about 900 ℃, and the particle size increases with the sintering temperature. Excitation and emission spectra of Tb^3+ doped LuAG films were measured. The effects of heat-treatment temperature and doping concentration of Th3 + on the luminescent properties were also investigated. For a comparison study, Th^3+-doped LuAG powders were also prepared by the same sol-gel method.
基金the support from National Natural Science Foundation of China (22208355, 22178363 and 21978300)the financial support and mica samples from Changzi Wu and RIKA technology CO., LTD.
文摘The performance of pearlescent pigment significantly affected by the grain size and the roughness of deposited film. The effect of TiCl_(4) concentration on the initial deposition of TiO_(2) on mica by atmospheric pressure chemical vapor deposition(APCVD) was investigated. The precursor concentration significantly affected the deposition and morphology of TiO_(2) grains assembling the film. The deposition time for fully covering the surface of mica decreased from 120 to 10 s as the TiCl_(4) concentration increased from 0.38%to 2.44%. The grain size increased with the TiCl_(4) concentration. The AFM and TEM analysis demonstrated that the aggregation of TiO_(2) clusters at the initial stage finally result to the agglomeration of fine TiO_(2) grains at high TiCl_(4) concentrations. Following the results, it was suggested that the nucleation density and size was easy to be adjusted when the TiCl_(4) concentration is below 0.90%.
基金This study was financially supported by the National Natural Science Funds of China(No.21905040)the Startup Funds from the University of Electronic Science and Technology of China,the National Key Research and Development Program of China(Nos.2017YFB0702802 and 2018YFB0905400)Shanghai Venus Project(No.18QB1402600).
文摘As a promising solid electrolyte for thin-film lithium batteries,the amorphous Li_(0.33)La_(0.56)TiO_(3)(LLTO)thin film has gained great interest.However,enhancing ionic conductivity remains challenging in the field.Here,a systematical study was performed to improve the ionic conductivity of sputter-deposited LLTO thin films via the optimization of processing atmosphere and temperature.By combining the optimized oxygen partial pressure(30%),annealing temperature(300℃),and annealing atmosphere(air),an amorphous LLTO thin film with an ionic conductivity of 5.32910^(-5)·S·cm^(-1) at room temperature and activation energy of 0.26 eV was achieved.The results showed that,first,the oxygen partial pressure should be high enough to compensate for the oxygen loss,but low enough to avoid the abusive oxygen scattering effect on lithium precursors that results in a lithium-poor composition.The oxygen partial pressure needs to achieve a balance between lithium loss and oxygen defects to improve the ionic conductivity.Second,a proper annealing temperature reduces the oxygen defects of LLTO thin films while maintaining its amorphous state,which improves the ionic conductivity.Third,the highest ionic conductivity for the LLTO thin films that were annealed in air(a static space without a gas stream)occurs because of the decreased lithium loss and oxygen defects during annealing.These findings show that the lithium-ion concentration and oxygen defects affect the ionic conductivity for amorphous LLTO thin films,which provides insight into the optimization of LLTO thin-film solid electrolytes,and generates new opportunities for their application in thinfilm lithium batteries.
基金supported by the National Natural Science Foundation of China(51972094 and 52002107)Hebei Provincial Department of Science and Technology(236Z4403G)+1 种基金Research Innovation Team Project of Hebei University(IT2023A04,150000321008)supported in part by the Micro-analysis Center and the High-Performance Computing Center of Hebei University。