Pure and neodymium-doped gadolinium calcium oxoborate crystals of high quality were grown by the Czochralski method.The orientation of crystal was precisely determined,and the samples for measurements were prepared.Th...Pure and neodymium-doped gadolinium calcium oxoborate crystals of high quality were grown by the Czochralski method.The orientation of crystal was precisely determined,and the samples for measurements were prepared.Through synchrotron x-ray topography and high-resolution x-ray diffractometry,the twin structure was discovered.Some properties such as the figure of merit value,and dielectric,piezoelectric,and elastic constants were meausured along with a discussion of the anisotropy of the laser properties.展开更多
采用熔盐顶部籽晶法从K 2 Mo 3 O 10-B 2 O 3助熔剂中生长出尺寸为20 mm的优质GdAl 3(BO 3)4(简称GAB)和Nd^3+激活的自变频激光晶体。确定了GAB晶体的透光波长范围、折射率和倍频系数随波长的变化,结果表明其在整个透光范围内均可实现...采用熔盐顶部籽晶法从K 2 Mo 3 O 10-B 2 O 3助熔剂中生长出尺寸为20 mm的优质GdAl 3(BO 3)4(简称GAB)和Nd^3+激活的自变频激光晶体。确定了GAB晶体的透光波长范围、折射率和倍频系数随波长的变化,结果表明其在整个透光范围内均可实现相位匹配。测定了Nd^3+∶GAB晶体在室温下的偏振吸收、荧光光谱和荧光寿命,进行了光谱计算,测试了晶体的自变频激光性能,实现了紫外-可见光-红外-中红外多波段激光输出。展开更多
Doping modification of electrode materials is a sought-after strategy to improve their electrochemical performance in the secondary batteries field. Herein,polyanion（BO3）^3-doped Li3V2（PO4）3 cathode materials were...Doping modification of electrode materials is a sought-after strategy to improve their electrochemical performance in the secondary batteries field. Herein,polyanion（BO3）^3-doped Li3V2（PO4）3 cathode materials were successfully synthesized via a wet coordination method. The effects of（BO3）^3- doping content on crystal structure, morphology and electrochemical performance were explored by X-ray diffraction（XRD）, scanning electron microscopy（SEM）, cyclic voltammetry（CV） and electrochemical impedance spectroscopy（EIS）. All the asprepared samples have the same monoclinic structure;among them, Li3V2（PO4）（2.75）（BO3）（0.15） sample has relatively uniform and optimized particle size. In addition, this sample has the highest discharge capacity and the best cycling stability, with an initial discharge capacity of 120.4mAh·g^-1, and after 30 cycles at a rate of 0.1C, the discharge capacity still remains 119.3 mAh·g^-1. It is confirmed that moderate polyanion（BO3）^3- doping can rearrange the electronic structure of the bulk Li3V2（PO4）3,lower the charge transfer resistance and further improve the electrochemical behaviors.展开更多
文摘Pure and neodymium-doped gadolinium calcium oxoborate crystals of high quality were grown by the Czochralski method.The orientation of crystal was precisely determined,and the samples for measurements were prepared.Through synchrotron x-ray topography and high-resolution x-ray diffractometry,the twin structure was discovered.Some properties such as the figure of merit value,and dielectric,piezoelectric,and elastic constants were meausured along with a discussion of the anisotropy of the laser properties.
文摘采用熔盐顶部籽晶法从K 2 Mo 3 O 10-B 2 O 3助熔剂中生长出尺寸为20 mm的优质GdAl 3(BO 3)4(简称GAB)和Nd^3+激活的自变频激光晶体。确定了GAB晶体的透光波长范围、折射率和倍频系数随波长的变化,结果表明其在整个透光范围内均可实现相位匹配。测定了Nd^3+∶GAB晶体在室温下的偏振吸收、荧光光谱和荧光寿命,进行了光谱计算,测试了晶体的自变频激光性能,实现了紫外-可见光-红外-中红外多波段激光输出。
基金financially supported by the National Key Research and Development Program of China(No.2016YFB0100500)the Beijing Co-construction Project(No.20150939014)
文摘Doping modification of electrode materials is a sought-after strategy to improve their electrochemical performance in the secondary batteries field. Herein,polyanion（BO3）^3-doped Li3V2（PO4）3 cathode materials were successfully synthesized via a wet coordination method. The effects of（BO3）^3- doping content on crystal structure, morphology and electrochemical performance were explored by X-ray diffraction（XRD）, scanning electron microscopy（SEM）, cyclic voltammetry（CV） and electrochemical impedance spectroscopy（EIS）. All the asprepared samples have the same monoclinic structure;among them, Li3V2（PO4）（2.75）（BO3）（0.15） sample has relatively uniform and optimized particle size. In addition, this sample has the highest discharge capacity and the best cycling stability, with an initial discharge capacity of 120.4mAh·g^-1, and after 30 cycles at a rate of 0.1C, the discharge capacity still remains 119.3 mAh·g^-1. It is confirmed that moderate polyanion（BO3）^3- doping can rearrange the electronic structure of the bulk Li3V2（PO4）3,lower the charge transfer resistance and further improve the electrochemical behaviors.
