Ce掺杂Mn3O4及其电化学电容行为

用溶胶-凝胶方法合成了Mn₃O₄和Ce掺杂Mn₃O₄. 采用X射线衍射(XRD)、傅里叶变换红外(FT-IR)光谱、场发射扫描电镜(FESEM)和透射电子显微镜(TEM)对其结构和形貌进行了表征. 采用循环伏安、电化学交流阻抗和恒流充放电技术对其电化学性能进行了测试. 研究结果表明, Ce掺杂对Mn₃O₄的形貌和电化学性能均有显著影响. 当Ce离子占金属离子总量的3%时, 掺杂Mn₃O₄的单电极比电容高达477 F·g^-1, 比未掺杂的提高了43.7%, 并且表现出更好的循环稳定性.     

Sn掺杂二氧化锰超级电容器电极材料

用化学液相法制备了超级电容器用的Sn掺杂二氧化锰电极材料. 采用扫描电镜(SEM)、能谱仪(EDS)和X射线衍射(XRD)光谱对电极材料的形貌和物相进行表征. 结果表明, 所得样品由直径约10 nm, 长约100 nm的棒状物粘结成200-500 nm的球状物, 晶型为δ-MnO2. 循环伏安、电化学交流阻抗和恒流充放电测试表明, 化学掺杂的比例对材料的电化学性能有较大的影响. 当Mn:Sn的摩尔比为50:1时, 电极材料的比电容达到293 F·g-1, 比未掺杂的提高了64.6%. 600次充放电循环后, 比电容稳定在275 F·g-1, 表现出良好的容量保持能力.     

掺杂Y3+和Gd3+的 Phen-Eu(Ⅲ)二元固体配合物的红外及荧光光谱研究

合成了掺杂Y^3 和Gd^3 的Phen-Eu(Ⅲ）二元固体配合物，确定了它们的组成，测定了固体配合物的红外光谱和荧光光谱，并首次探讨了掺杂Y^3 和Gd^3 的Phen-Eu(Ⅲ）二元固体配合物荧光强度的影响。     

涂料中甲醛的分光光度测定新方法

在FeCl3存在的盐酸介质中,甲醛与蛋白胨反应生成紫色化合物,最大吸收波长555 nm,甲醛浓度在1~25μg/10 mL范围内,吸光度与浓度成线性关系,线性相关系数r2=0.9997,检出限0.05μg/mL。用本法测定经活性炭脱色的水溶性涂料中的甲醛含量,回收率为96.46%~103.32%,相对标准偏差(n=6)为1.36%~2.09%。     

Fabrication of high performance Matrimid/polysulfone dual-layer hollow fiber membranes for O2/N2 separation

Matrimid/polysulfone (PSf) dual-layer hollow fiber membranes were fabricated by using co-extrusion and dry-jet wet-spinning phase-inversion techniques. The effects of the spinning dope composition, spinneret dimension, spinneret temperature and the air gap distance on the hollow fiber membranes separation performance were studied. Aging phenomenon was also studied. After coated by 3 wt% silicon solution, the hollow fiber membranes have an O₂/N₂ selectivity of 7.55 at 25 °C, 506.625 kPa which exceeds the intrinsic value of Matrimid. The membranes have an O₂ permeance of 9.36 GPU with an apparent dense-layer thickness of 1421 Å calculated from the O₂ permeability. SEM images show the high porosity underneath the dense skin. It indicates that non-solvent addition is not necessary in the inner spinning dope to induce the macroviod formation. The binodals of the Matrimid/solvent/H₂O and PSf/solvent/H₂O indicate that the composition of the spinning dope plays an important role in the structure and the gas separation performance of the dual-layer hollow fiber membranes. The delayed demixing of the inner spinning dope may fabricate low resistance support layers in the dual-layer hollow fiber membranes.     

Growth of nitrogen-doped p-type ZnO films by spray pyrolysis and their electrical and optical properties

Nitrogen-doped ZnO films were deposited on silicon (1 0 0) substrate using zinc acetate and ammonium acetate aqueous solution as precursors by ultrasonic spray pyrolysis. Successful p-type doping can be realized at optimized substrate temperature. The p-type ZnO films show excellent electrical properties such as hole concentration of 10¹⁸ cm⁻³, hole mobility of 10² cm² V⁻¹ s⁻¹ and resistivity of 10⁻² Ω cm. In the photoluminescence measurement, a strong near-band-edge emission was observed, while the deep-level emission was almost undetectable in both undoped and N-doped ZnO films. The growth and doping mechanism of N-doped ZnO films were discussed.     

掺溴聚-4-甲基-1-戊烯的合成研究

 液溴与聚-4-甲基-1-戊烯（PMP）的四氯化碳溶液反应，在光照条件下得到溴代PMP，通过红外与元素分析确证了其结构。并通过热重分析对其性能进行了初步的研究。研究发现，在光照条件下溴原子很容易与PMP中叔丁基上的氢原子发生取代反应，得到化学掺杂溴原子的聚合物。该聚合物在150℃以下比较稳定，在150℃以上就会失去HBr。采用此种方法，可得到掺杂均匀的低密度材料。     

不同方法掺杂Au对纳米α-Fe2O3气敏性能的影响

分别采用共沉淀法、浸渍法、紫外辐照法制备了掺杂不同Au含量的α-Fe2O3纳米粉体,并制作了旁热式厚膜型气敏元件.用XRD、TG-DTA和TEM技术对纳米晶的晶型、晶粒大小及形貌进行了表征.考察了掺杂方法、Au含量及焙烧温度对α-Fe2O3气敏性能的影响.结果表明,采用三种方法掺杂适量Au后,都使α-Fe2O3的气敏性有了显著提高,其中采用共沉淀法,在400℃焙烧的Au质量分数为1.5%的α-Fe2O3的气敏性最佳.     

水热法制备掺杂铁离子的TiO2纳米粒子及其光催化反应研究

以TiCl4为前驱体, 采用水热法制备了掺杂铁离子的TiO2纳米粒子, 利用XRD对不同条件下制备的产物进行了表征, 探讨了反应温度、 胶体溶液pH值和反应时间对水热反应的影响. 考察了所制备的Fe3+-TiO2纳米粒子光催化降解罗丹明B的催化性能, 实验发现, 制备的掺杂0.1%Fe3+-TiO2纳米粒子与纯TiO2相比, 具有更好的催化活性.     

Improvement of electrochemical properties of LiFePO4/C cathode materials by chlorine doping

The olivine-type cathode materials of LiFePO₄ were prepared via solid-state reaction under argon atmosphere and doped by chlorine to improve their electrochemical performances. The crystal structure, morphology, and electrochemical properties of the prepared samples were investigated using thermogravimetry–differential scanning calorimetry, X-ray diffraction, Fourier transform infrared, scanning electron microscopy, cyclic voltammetry, and charge–discharge cycle measurements. The result showed that the electrochemical performance of LiFePO₄ had been improved by chlorine doping, and the effect of chlorine in lattice was discussed. The heavily doped samples show better electrochemical performance in relative high rates.