共查询到17条相似文献,搜索用时 984 毫秒
1.
2.
3.
4.
5.
6.
Sm_(0.9)Sr_(0.1)FeO_3的制备及其气敏性能 总被引:2,自引:1,他引:1
用Sr对SmFeO3进行A位掺杂,用柠檬酸盐sol-gel法制得Sm0.9Sr0.1FeO3粉体。对其进行XRD表征,并制成气敏元件。采用静态配气法测试其气敏性能。结果表明:该粉体为斜方晶系钙钛矿结构,平均晶粒尺寸约为25nm。在空气中的电导较SmFeO3高50倍左右,最佳工作温度下降160℃。在220℃的最佳工作温度下,气敏元件对体积分数为5×10–4乙醇的灵敏度高达56,且其选择性好,响应–恢复时间分别为40s和50s,有望开发成为对乙醇检测的气敏材料。 相似文献
7.
8.
采用传统固相合成法制备了Pb(Mn1/3Sb2/3)O3掺杂的(1–x)(Pb0.92Ba0.02Sr0.06)(Zr0.52Ti0.48)O3-xPb(Mn1/3Sb2/3)O3[xPMS-(1–x)PBSZT]压电陶瓷。通过XRD、SEM和准静态d33仪等手段探讨了PMS掺杂量对xPMS-(1–x)PBSZT陶瓷样品的相结构、显微结构和电性能的影响。结果表明:适量的PMS掺杂有助于降低陶瓷样品的烧结温度,x=0.01的样品在1 230℃烧结具有最大体积密度7.83 g/cm3。当x=0.02时,其具有最佳综合电性能,主要参数为:d33=349pC/N,kp=0.592,εr=1 587,tanδ=0.46%。 相似文献
9.
10.
研究了Zr和Ti复合取代Ca[(Li1/3Nb2/3)0.95Zr0.15-xTix]O3+δ(0≤x≤0.15,CLNZT)陶瓷B位对其晶体结构及微波介电性能的影响,并分析了谐振频率温度系数τf随容忍因子t的变化关系。当0≤x≤0.15时,CLNZT陶瓷为单一斜方钙钛矿相,随x的增加,τf由–9.4×10–6/℃变为–15.8×10–6/℃,而品质因数与谐振频率乘积Q·f值先增大,x=0.10时又开始下降。当x=0.10时,陶瓷具有较好的微波介电性能:εr为32.8,Q·f值为1.66×104GHz,τf为–13.6×10–6/℃。 相似文献
11.
12.
添加质量分数为1%的H3BO3为助烧剂。研究了Ba5(Nb1–xSbx)4O15(0≤x≤0.2)陶瓷的烧结特性、显微结构和微波介电性能。结果表明:当x≤0.15时,该类陶瓷可在900℃附近烧结,并伴有少量BaSb2O6和BaB2O4相;随着x从0增加到0.2,εr和τf均有较大幅度下降;Q.f先升后降。在900℃烧成温度下,x为0.15的陶瓷获得较好的微波介电性能:εr为29.21,Q.f为13 266 GHz,τf为11×10–6℃–1,并能与Ag电极很好相容,基本满足LTCC工艺的要求。 相似文献
13.
CSBT-BNT-NT系高介瓷料α_ε系列化的研究 总被引:2,自引:1,他引:1
进行了具有高介电常数的 (Ca,Sr,Ba) Ti O3(CSBT) - Ba6 - 3x Nd8+ 2 x Ti1 8O5 4 (BNT) - Nd2 Ti2 O7(NT)系瓷料介电常数温度系数 (αε)系列化的研究 ,采用多相混合控制技术 ,按李赫涅德凯混合法则 ,调整该三元系瓷料αε系列。研制的瓷料介电性能 :εr=90~ 15 0 ;tgδ( 2 0℃ ,1 MHz) ≤ (0 .5~ 5 .0 )× 10 - 4 ;αc( - 2 5~ + 85℃ ) =((0~ - 75 0 )± 6 0 )× 10 - 6℃ - 1 ;ρv( 2 0℃ ,DC 1 0 0 V) ≥ 10 1 2 Ω· cm。 相似文献
14.
S. R. Samedov O. Baykan A. Gulubayov 《Journal of Infrared, Millimeter and Terahertz Waves》2004,25(5):735-747
Near IR properties of the mixed TlInS2xSe2(1?x) have been studied previously by the present authors. In this work the temperature and frequency dependence's of the conductivity and the current-voltage characteristics (in relatively weak electric field), have been investigated for monoclinic TlInS2xSe2(1?x) crystals, which are perspective materials for IR applications. From the temperature dependence's of conductivity in the direction perpendicular to c- axis the band gap Eg = 2.22 eV was determined for β--TlInS2 crystals. The impurity centres were determined located at 0.43, 0.73 eV and 0.35, 0.48, 1.12 eV for the direction of current i//c and i ⊥ c, respectively. The concentration of the centres located at 0.48 and 1.12 eV were calculated to be NA ? ND = 4.8 · 109 cm?3 and 1.9 · 1011 cm?3, respectively. It was found that in the solid solutions TlInS2xSe2(1?x) for 0.3 ≤ x ≤ 1, the conductivity follows the dependence σ (v) = σ0·υs in the temperature range between 100 to 600 K. In the temperature range of 80-400 K charge bounce plays an important role in the conductivity mechanism. Occurrence of the deep and low-levels impurity centres and a “tail” of the density of energy states in TlInS2xSe2(1?x) crystals make them perspective for practical applications: switching and memory effects, N-type current-voltage characteristics, induced conductivity etc. 相似文献
15.
16.
17.
Hydrogenated (annealed in hydrogen atmosphere) cadmium oxide (CdO) thin films co-doped with iron (Fe) of different levels and fixed (2.5%) copper (Cu) amount were deposited on glass and silicon wafer substrates by thermal evaporation. The films were characterised with X-ray fluorescence, X-ray diffraction, optical spectroscopy, and dc-electrical measurements. The obtained results show important improvements in the conductivity, mobility, and carrier concentration compared to un-doped and non-hydrogenated CdO. Hydrogenated CdO doped with 2.5% Cu and 1.3% Fe improved the conductivity (2293.6 S/cm) by ~46 times, mobility (78.31 cm2/V s) by ~11 times, and carrier concentration (1.82×1020 cm−3) by ~4 times. This suggests the possibility of using CdO:Cu:Fe–H as transparent-conducting-oxide and dilute-magnetic-semiconductor field of applications. 相似文献