稀有金属材料与工程
稀有金屬材料與工程
희유금속재료여공정
RARE METAL MATERIALS AND ENGINEERNG
2010年
3期
523-527
,共5页
杨双%李昕%王进福%吴丽平
楊雙%李昕%王進福%吳麗平
양쌍%리흔%왕진복%오려평
稀土多元渗%Ln_xMo_yC%导电率
稀土多元滲%Ln_xMo_yC%導電率
희토다원삼%Ln_xMo_yC%도전솔
rare earth co-permeation%Ln_xMo_yC%conductivity
为扩大碳化铝在导电材料方面的应用,研究稀土碳化钼Ln_xMo_yC的制备方法及其导电性.采用稀土多元渗法,以(NH_4)_3[CrMO_6O_(24)H_6]·7H_2O为前驱体制备Ln_xMo_yC.用X射线衍射、电子探针X射线能谱、光电子能谱和四探针电极等手段对其结构、元素含量、价态及电性能等进行测试.结果表明:生成的L_xMo_yC是六方密堆结构;渗入的微量稀土元素对其导电性产生了影响;La_(0.00593)Nd_(0.00562)Sm_(0.00502)Gd_(0.00500)Mo_(1.98)C(简写为LNSGMC)的室温电导率(4.692×10~(2S·cm~(-1)比用传统方法得到的最高值(1.025×10~-2S·cm~(-1)高近4.6倍,且在289~490K范围内其表现出金属导电行为,在490~550 K范围内却表现出显著的半导体导电行为.
為擴大碳化鋁在導電材料方麵的應用,研究稀土碳化鉬Ln_xMo_yC的製備方法及其導電性.採用稀土多元滲法,以(NH_4)_3[CrMO_6O_(24)H_6]·7H_2O為前驅體製備Ln_xMo_yC.用X射線衍射、電子探針X射線能譜、光電子能譜和四探針電極等手段對其結構、元素含量、價態及電性能等進行測試.結果錶明:生成的L_xMo_yC是六方密堆結構;滲入的微量稀土元素對其導電性產生瞭影響;La_(0.00593)Nd_(0.00562)Sm_(0.00502)Gd_(0.00500)Mo_(1.98)C(簡寫為LNSGMC)的室溫電導率(4.692×10~(2S·cm~(-1)比用傳統方法得到的最高值(1.025×10~-2S·cm~(-1)高近4.6倍,且在289~490K範圍內其錶現齣金屬導電行為,在490~550 K範圍內卻錶現齣顯著的半導體導電行為.
위확대탄화려재도전재료방면적응용,연구희토탄화목Ln_xMo_yC적제비방법급기도전성.채용희토다원삼법,이(NH_4)_3[CrMO_6O_(24)H_6]·7H_2O위전구체제비Ln_xMo_yC.용X사선연사、전자탐침X사선능보、광전자능보화사탐침전겁등수단대기결구、원소함량、개태급전성능등진행측시.결과표명:생성적L_xMo_yC시륙방밀퇴결구;삼입적미량희토원소대기도전성산생료영향;La_(0.00593)Nd_(0.00562)Sm_(0.00502)Gd_(0.00500)Mo_(1.98)C(간사위LNSGMC)적실온전도솔(4.692×10~(2S·cm~(-1)비용전통방법득도적최고치(1.025×10~-2S·cm~(-1)고근4.6배,차재289~490K범위내기표현출금속도전행위,재490~550 K범위내각표현출현저적반도체도전행위.
In order to extend the application of Mo_2C as electric materials, the preparation of RE molybdenum carbide Ln_xMo_yC by means of rare earth co-permeation with (NH_4)_3[CrMo_6O_(24)H_6]·7H_2O as the precursor and its conductivity were studied.XRD,EDS,XPS and four-probe poles were used to characterize the structure, element content, valences and conductivity bf Ln_xMo_yC. Results show that the structure of the prepared L_xMo_yC is single hexagonal close-packed (hcp) and some rare earth elements such as Nd, Gd, La and Sm permeated into crystal phase of molybdenum carbide have influence on its conductivity. The conductivity of LNSGMC La_(0.00593)Nd_(0.00562)Sm_(0.00502)Gd_(0.00500)Mo_(1.98C) at room temperature is 1.692×10~2 S·cm~(-1),which is 4.6 times higher than the highest value (1.025×10~2S·cm~(-1) by conventional methods. In the range of 289-490 K,it shows meallic conductivity while in 490-550 K range it shouw obvious semiconductor conductivity.