多孔氧化铝有序膜的制备研究

本文用阳极氧化法分别在硫酸和草酸电解液中成功制备出高度有序、具有纳米级孔洞的氧化铝有序阵列模板。采用饱和HgCl₂去除Al基体后,得到典型六方形结构的多孔Al₂O₃有序膜。通过改变氧化电压、氧化时间等条件使模板的孔径、孔深可调、膜厚度可控,并系统研究了对模板有序性、孔径、膜厚度等的影响因素,总结出制备Al₂O₃有序膜的最佳工艺。     

量子点或纳米材料发光现象—界面极化子和多孔硅发光

量子点中的极化子效应是当前量子点研究中的重要问题,其特征急需了解,文章在综述了量子点中限域极化子的概念、可能性和能量随尺寸的变化规律之后,提出了界面限域极化子模型,该模型首次指明本征声子和外来声子都地界面限域分子化的形成有贡献,作者利用此模型分析了多孔硅体系中的光谱特征,证实了表面覆有氧化层的纳米硅的行为十分符合量子限域极化子的特征,这一极化子模型与单个纳米硅结构的发光谱十分一致,此结果对最终揭示多孔硅发光机理有重要意义。     

Free-standing,curled and partially reduced graphene oxide network as sulfur host for high-performance lithium–sulfur batteries

Lithium–sulfur(Li–S) batteries have received more and more attention because of higher specific capacity and energy density of sulfur than current lithium–ion batteries. However, the low electrical conductivity of sulfur and its discharge product, and also the high dissolution of polysulfides restrict the Li–S battery practical applications. To improve their performances, in this work, we fabricate a novel free-standing, curled and partially reduced graphene oxide(CPrGO for short) network and combine it with sulfur to form a CPrGO–S composite as a cathode for Li–S battery. With sulfur content of 60 wt%, the free-standing CPrGO–S composite network delievers an initial capacity of 988.9 m Ah·g~(-1). After 200 cycles,it shows a stable capacity of 841.4 m Ah·g~(-1) at 0.2 C, retaining about 85% of the initial value. The high electrochemical performance demonstrates that the CPrGO–S network has great potential applications in energy storage system. Such improved properties can be ascribed to the unique free-standing and continous CPrGO–S network which has high specific surface area and good electrical conductivity. In addition, oxygen-containing groups on the partially reduced graphene oxide are beneficial to preventing the polysulfides from dissolving into electrolyte and can mitigate the "shuttle effect".     

碳纳米管柔性应变传感器的研究

<正>传感器(sensor),顾名思义,是一种传递"感觉"的仪器;所谓"感觉",就是各种物理、化学信号。传感器可以将某种物理信号转换为另一种可观察或者可测量的(电、光)信号。水银温度计可以看成一种最简单的传感器,它利用水银热胀冷缩的特性把温度转换为水银柱的高度,人们通过观察水银柱的高度就可以间接地、定量的测知温度值。常用的传感器有温度传感器(热敏电阻、热电偶)、压力     

大直径半导体碳纳米管手性结构实现宏量分离

正从概念上讲,碳纳米管是由石墨烯卷曲形成的一维管状分子,它不仅具有石墨烯优异的力学、热学性能以及极高的载流子迁移率等特点,而且具有结构可调的能隙结构,表现出优异的电子以及光电子特性~([1]),是制备高速、低功耗、高集成度电子和光电子集成回路的理想材料。相对于传统的Si基半导体器件,碳纳米管电子器件的能效能够提高一个数量级以上,而且能够有效克     

ELECTRONIC STRUCTURE STUDIES OF THE C60 FILM CONDENSED ON 2H-MoS2(0001) SURFACE

The electronic structure and vibrational spectrum of the C₆₀ film condensed on a 2H- MoS₂(0001) surface have been investigated by X-ray photoelectron spectroscopy (XPS), ul-traviolet photoelectron spectroscopy (UPS), Auger electron spectroscopy (AES) and infrared high-resolution electron-energy-loss spectroscopy (HREELS). AES analysis showed that at low energy side of the main transition, C₆₀ contains a total of three peaks just like that of graphite. However, the energy position of the KLL main Auger transition of C₆₀ looks like that of diamond, indicating that the hybridization of the carbon atoms in C₆₀ is not strictly in sp²- bonded state but that the curvature of the molecular surface introduces some sp²pz- bonded character into the molecular orbitals. XPS showed that the C 1s binding energy in C₆₀ was 285.0eV, and its main line was very symmetric and offered no indication of more than a single carbon species. In UPS measurement the valence band spectrum of C₆₀ within 10eV below the Fermi level (E_F) shows a very distinct five-band structure that character-izes the electronic structure of the C₆₀ molecule. HREEL results showed that the spectrum obtained from the C₆₀ film has very rich vibrational structure. At least, four distinct main loss peaks can be identified below 200 meV. The most intense loss was recorded at 66 meV, and relatively less intense losses were recorded at 95, 164 and 197meV at a primary energy of electron beam E_P = 2.0eV. The other energy-loss peaks at 46, 136, 157 and 186meV in HREEL spectrum are rather weak. These results have been compared to infrared spectrum data of the crystalline solid C₆₀ taken from recent literatures.     

表面包敷1-壬基硫醇的银纳米粒子形成过程及其自组织有序阵列

用紫外-可见光谱和透射电子显微镜研究了表面包敷有1-壬基硫醇的银纳米粒子的形成过程.结果表明,银纳米粒子的形成是先快速形成较大粒子,然后是粒子分解和轻微长大的动态过程.     

怀念恩师陆学善先生

1978年,中国大地上发生了许多意想不到的变化,其中恢复研究生招生工作像一股春风将我从西北高原送到了中关村的学术殿堂.我有幸成为陆学善先生的入门弟子.     

化学热解—一种优异的制备纳米材料的方法（Ⅱ）

3 2　第二类氧化物纳米微粒第二类氧化物纳米微粒因其特有的物理性质和潜在的应用前景得到广泛的研究 ,其特有的物理性质主要包括电 -光性、发光性、磁 -光性、声 -光性、铁电性、压电特性、电磁波吸收特性、光电性以及光或电致发光的性质 .所有这些性质正是现代电子学、通信和显示等实际应用的基础 .上面所有的物理性质在诸如钛酸盐、铌酸盐和亚锰酸盐等过渡金属氧化物中都有很好的体现 .一些铜酸盐高温超导体同样是很好的功能材料 ,将在后面进行详细讨论 .Ｙａｎｇ等用醋酸水溶液沉淀法 (ＤＡＡＳ)成功制备了磁阻性的Ｌａ Ｓｒ Ｍｎ Ｏ(Ｌ…     

近场光学扫描显微术

 80年代初期,人们对物理现象的观察和理解,经历了一场大变革。这场变革的标志,就是新一代成象系统的诞生。