Lei Miao
,
Sakae Tanemura
,
Thi Hue Nguyen
,
Li Luo
,
Masaki Tanemura
,
Shoichi Toh
,
Kenji Kaneko
,
Masahiro Kawasaki
材料科学技术（英文）
An alternative sol-gel method has been applied to fabricate anatase and rutile TiO2 coatings uniformly on Al scale fibers with very thin naturally oxidized layer from mixed precursors of Ti tetraisopropoxide, acetyl acetone, deionizer water and ethanol in different molar ratios. The crystal structure of TiO2 coatings on Al scale fiber was confirmed by both XRD and TEM. The surface morphology of the coatings was observed by SEM and the chemical composition of the grown TiO2 was analyzed by EDS in TEM. Anatase coating, having a fine crystalline structure, was grown at 450℃ while rutile was being done at 670℃. The TEM results indicated that the fabricated TiO2 coatings consisted of anatase/rutile polycrystalline structures. The optimal fabrication conditions for TiO2 coatings with about 400 nm in thickness on Al scale fibers were established through the characterization results.
关键词:
Sol-gel method
,
null
,
null
,
null
,
null
Yuxian HAN
,
Tai QIU
材料科学技术（英文）
Sol-gel method was employed for the preparation of nanoscale tungsten powder. The effects of different preparation conditions on particle size were discussed and the optimum preparation condition was found. The products were characterized by X-ray diffraction, scan electron microscopy and so on. The results show that the intermediate is monoclinic WO3, its particle shape is approximately spherical, and the particle size distribution is narrow. The average particle size is about 60 nm. After deoxidization, WO3 turns into cubic tungsten powder with small particle size (average particle size about 120 nm) and narrow size distribution.
关键词:
Sol-gel method
,
null
,
null
,
null
Rui Ding Chunxiang Xu Baoxiang Gu Zengliang Shi Haitao Wang Long Ba
材料科学技术（英文）
Well-crystallized MgZnO alloy thin films with hexagonal wurtzite structure were fabricated by sol-gel method. With the band gap increases, the surface roughness and the grain size reduces. It is worth noting that the intensity of the band-edge luminescence of Mg doped films enhances with the increase of the Mg content. The microstructure and photoluminescence mechanism have been discussed based on X-ray diffraction patterns, atomic force microscopy images, ultraviolet-visible absorption spectra, photoluminescence spectra and Fourier transform infrared spectra.
关键词:
null
,
Optical properties
,
Sol-gel method
Shixi ZHAO
,
Hanxing LIU
,
Qiang LI
,
Shixi OUYANG
材料科学技术（英文）
Orthorhombic LiMnO2 cathode materials were synthesized successfully at lower temperature by sol-gel method. When LiMnO2 precursor prepared by sol-gel method was fired in air, the product was a mixture of spinel structure LiMn2O4 and rock-salt structure Li2MnO3, whereas in argon single-phase orthorhombic LiMnO2 could obtain at the range of 750℃ to 920℃. The substitution of Mn by Zn2+ or Co3+ in LiMnO2 led to the structure of LiMnO2 transiting to α-LiFeO2. The results of electrochemical cycles indicated that the discharged capacity of orthorhombic-LiMnO2 was smaller at the initial stages, then gradually increased with the increasing of cycle number, finally the capacity stabilized to certain value after about 10th cycles. This phenomenon reveals that there is an activation process for orthorhombic LiMnO2 cathode materials during electrochemical cycles, which is a phase transition process from orthorhombic LiMnO2 to tetragonal spinel Li2Mn2O4. The capacity of orthorhombic LiMnO2 synthesized at lower temperature is larger than that synthesized at high temperature.
关键词:
Orthorhombic LiMnO2
,
null
,
null
,
null
黄凤群
,
王治
,
成宁宁
材料开发与应用
doi:10.3969/j.issn.1003-1545.2012.03.010
采用溶胶凝胶自燃烧法制备了Mn0.4Zn0.6-xCoxFe2O4铁氧体,研究了钴掺杂对其结构和磁性质的影响.将自燃烧法制备的粉末进行1,150℃烧结.利用X射线衍射仪对制备的粉末测试发现,Mn0.4Zn0.6-xCoxFe2O4系列铁氧体都具有尖晶石结构.利用VSM对铁氧体进行磁性测试,发现饱和磁化强度与晶格常数的变化规律一致,在钴含量为0.2时,都取得最大值.通过μi-T曲线发现,初始磁导率随着钴含量的增加而降低,居里温度是一个常数.而且,钴含量可以调节磁导率的温度稳定性,在钴含量为0.3时,磁导率具有优良的温度稳定性.基于铁氧体中离子分布的原理,阐明了钴掺杂对铁氧体磁导率温度稳定性的作用机理.
关键词:
锰锌铁氧体
,
溶胶凝胶自燃烧法
,
钴掺杂
,
磁性能
闫海乐
,
茹红强
,
喻亮
,
里景阳
,
魏文韬
,
岳新艳
材料导报
以无机盐Al(NO_3)_3·9H_2O为先驱体、水为溶剂,加入不同浓度的胶溶剂HNO_3,采用溶胶-凝胶(Solgel)法制备了勃姆石(γ-AlOOH)溶胶.分别以溶液下降法和真空浸渍法在三维网络碳化硅陶瓷骨架(3D-SiC)表面浸涂γ-AlOOH溶胶,采用不同烧结制度在3D-SiC表面生成了Al_2O_3薄膜.采用X射线衍射仪(XRD)、红外光谱仪(IR)和扫描电子显微镜(SEM)分析了薄膜的物相和显微结构,并检测了薄膜的抗热震性.结果表明,采用真空浸渍法在3D-SiC表面浸涂加入浓度0.22mol/L HNO_3制备的γ-AlOOH溶胶能烧结形成致密平整的Al_2O_3薄膜.升高烧结温度,Al_2O_3晶粒长大,900℃时薄膜最致密且能观测到玻璃态显微结构.薄膜的抗热震性随烧结温度升高而提高.
关键词:
溶胶-凝胶法
,
真空浸渍法
,
Al_2O_3
,
薄膜
,
三维网络碳化硅
,
抗热震性
程祖军
,
曹美玲
,
潘丽坤
,
孙卓
功能材料与器件学报
doi:10.3969/j.issn.1007-4252.2009.03.016
稀土元素铕通过溶胶凝胶法掺入到多孔二氧化硅制成的减反射膜层中,并被用来提高硅太阳能电池的转换效率.在标准测试条件下,和用超白钢化玻璃相比较,该掺入铕的二氧化硅减反射薄膜使太阳能电池的效率提高了9.5%.
关键词:
太阳能电池
,
转换效率
,
铕
,
溶胶凝胶法
,
二氧化硅减反射膜
赵彦伟
,
周延春
,
刘宏瑞
,
李军平
,
孙文婷
宇航材料工艺
doi:10.3969/j.issn.1007-2330.2014.04.001
综述了国内外ZrB2粉体制备技术如固相法、液相法和气相法的研究进展,详细分析了各种制备技术的特点,并展望了ZrB2粉体制备技术的发展方向.
关键词:
ZrB2
,
制备技术
,
硼/碳热还原法
,
溶胶-凝胶法
,
高频等离子体法
任军
,
郭长江
,
杨雷雷
,
李忠
催化学报
doi:10.1016/S1872-2067(12)60640-8
以硝酸铜和可溶性淀粉为原料,经过溶胶-凝胶化过程、高温炭化和KOH活化得到炭负载铜催化剂(Cu/C),采用扫描电镜、透射电镜、X射线衍射、热重-差热分析仪、N2吸附和CO程序升温脱附对催化剂结构进行了表征,并考察了它在甲醇氧化羰基化合成碳酸二甲酯(DMC)反应中的催化活性.结果表明,活化温度和KOH用量对催化剂的表面结构及金属铜粒子尺寸影响显著,当活化温度为850℃,KOH:C=l(质量比)时,Cu/C催化剂的比表面积达到1690m2/g,铜纳米粒子平均晶粒尺寸为30.4 nm,催化活性最高,DMC时空收率达到235.7 mg.g-1.h-1,甲醇转化率和DMC选择性分别为1.6％和76.5％.
关键词:
淀粉
,
溶胶凝胶法
,
炭载体
,
氢氧化钾活化
,
碳酸二甲酯
廖润华
,
李月明
,
江向平
,
王竹梅
,
张玉平
人工晶体学报
采用溶胶-凝胶法制备(1-x)Na0.5Bi0.5 TiO3-xK0.5Bi0.5TiO3体系无铅压电陶瓷.XRD分析表明,用溶胶-凝胶法可以在650℃下合成具有钙钛矿结构的(1-x)Na0.5Bi0.5TiO3-xK0.5Bi0.5TiO3粉体,且在x=0.18～0.30之间存在三方-四方准同型相界(MPB).陶瓷的压电性能参数表明,该体系在MPB组成范围内具有最佳的压电性能:x=0.30时,压电常数d33达到最大值(d33=150 Pc·N-1),平面机电耦合系数kp与介电常数εH33T/ε0均在x=0.26时达到最大值,分别为36.7%和1107.
关键词:
钛酸铋钠
,
溶胶-凝胶法
,
准同型相界
,
无铅压电陶瓷
