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101.
The as-sintered Zn1−xTixO (0.01 ≤ x ≤ 0.05) samples contained a solid solution of Zn1−xTixO with a wurtzite structure and a small amount of the cubic spinel Zn2TiO4. The amount of Zn2TiO4 increased with an increase in TiO2 content. The density and grain size increased with the small TiO2 content (≤0.01), and then they decreased gradually by further increasing the TiO2 content. The addition of TiO2 to ZnO led to a significant increase in the electrical conductivity and a decrease in the absolute value of the Seebeck coefficient, resulting in an increase in the power factor. The highest value of power factor (7.6 × 10−4 W m−1 K−2) was attained for Zn0.98Ti0.02O at 1073 K. It is demonstrated that the TiO2 addition is fairly effective for enhancing thermoelectric properties. 相似文献
102.
A method for low-temperature synthesis of a mixture of high-density ZnO nanoflakes and nanowires was developed to produce low-cost and high-efficiency gas sensors with ZnO nanostructures. ZnO nanoflakes and nanowires were grown on glass substrates by the RF sputter deposition of Zn particles and localized oxidation at a low temperature of 300 °C. The synthesized ZnO nanoflakes and nanowires were polycrystalline and had nanometer dimensions, as revealed by X-ray diffraction (XRD) and field emission scanning electron microscope (FESEM) measuring. A gas sensor based on the mixture of ZnO nanoflakes/nanowires responded rapidly and sensitively to ethanol. The sensing properties of the ZnO nanostructure sensor were approximately 72% for 50 ppm ethanol gas at an operating temperature of 100 °C. The response to 10 ppm of ethanol gas was 42% at the same temperature. 相似文献
103.
将4种质量分数(5%,10%,20%,30%)的Co(CH3COO)24H2O混合到四针状纳米ZnO原料里,采用超声化学浸泡法制备出表面改性四针状纳米ZnO颗粒。通过XRD和TEM分析了表面改性四针状纳米ZnO结构的物相和形貌特征。随着Co(CH3COO)24H2O质量分数增大,Co3O4相明显出现,Co3O4相沉积在ZnO表面上。研究表明:以表面改性四针状纳米ZnO粉末为原料制备的厚膜气敏元件,与纯ZnO气敏元件相比,Co(CH3COO)24H2O质量分数为5%的气敏元件对酒精和甲醇有较高的灵敏度,并讨论了表面改性对气敏性能的影响。 相似文献
104.
Jibo Qin Yibo Dou Jianchi Zhou Victor M. Candelario Henrik Rasmus Andersen Claus Hélix-Nielsen Wenjing Zhang 《Advanced functional materials》2023,33(28):2214839
The conversion of waste plastic into high-value-added chemicals is regarded as a promising approach for relieving global plastic pollution and contributing to the circular economy. Herein, a partial calcination strategy is developed to fabricate a zinc oxide/UiO66-NH2 (ZnO/UiO66-NH2) heterojunction, in which ZnO is encapsulated in porous UiO66-NH2 for the photocatalytic valorization of plastic. This strategy preserves the framework structure of UiO66-NH2, thus enabling the formation of ZnO with ultra-small size distributed inside the skeleton. The synergistic effect of the obtained ZnO/UiO66-NH2 heterojunction facilitates providing an efficient channel for carrier/mass transfer and guarantees structural stability. As a result, ZnO/UiO66-NH2 exhibits high activity for converting polylactic acid (PLA) and polyvinyl chloride (PVC) into acetic acid, coupled with H2 production. This work provides a feasible strategy for rationally designing heterojunction photocatalysts, as well as an insight into understanding the process of photocatalytic valorization of plastic. 相似文献
105.
The integration of piezoelectric materials onto carbon fiber (CF) can add energy harvesting and self-power sensing capabilities enabling great potential for “Internet of Things” (IoT) applications in motion tracking, environmental sensing, and personal portable electronics. Herein, a CF-based smart composite is developed by integrating piezoelectric poly(3,4-ethylenedioxythiophene) (PEDOT)/CuSCN-coated ZnO nanorods onto the CF surfaces with no detrimental effect on the mechanical properties of the composite, forming composites using two different polymer matrices: highly flexible polydimethylsiloxane (PDMS) and more rigid epoxy. The PDMS-coated piezoelectric smart composite can serve as an energy harvester and a self-powered sensor for detecting variations in impact acceleration with increasing output voltage from 1.4 to 7.6 V under impact acceleration from 0.1 to 0.4 m s−2. Using epoxy as the matrix for a CF-reinforced plastic (CFRP) device with sensing and detection functions produces a voltage varying from 0.27 to 3.53 V when impacted at acceleration from 0.1 to 0.4 m s−2, with a lower output compared to the PDMS-coated device attributed to the greater stiffness of the matrix. Finally, spatially sensitive detection is demonstrated by positioning two piezoelectric structures at different locations, which can identify the location as well as the level of the impacting force from the fabricated device. 相似文献
106.
在不同烧结温度下制备了氧化铝(Al2O3)掺杂的氧化锌(ZnO)压敏电阻,并对其进行扫描电子显微镜、X射线衍射、电流-电压、电容-电压测试以研究ZnO压敏电阻的微观结构和电气特性。结果表明:随着烧结温度的升高,Al2O3掺杂的ZnO压敏电阻泄漏电流得到了明显的抑制,这是由于施主密度和界面态密度不断增大,提高了晶界的势垒高度。而Al3+随着烧结温度的升高会不断地固溶入ZnO晶粒中,降低了晶粒电阻率,从而降低ZnO压敏电阻在通过大电流时的残压比。当烧结温度为1150℃时,ZnO压敏电阻的电气特性最佳,电压梯度为418.70 V/mm,泄漏电流为0.74,残压比为1.68,非线性系数为67.5,有助于提高ZnO避雷器的保护性能,实现深度限制电力系统,特别是特高压系统的过电压。 相似文献
107.
108.
Nanoplates: Synthesis of 2D Layered BiI3 Nanoplates,BiI3/WSe2van der Waals Heterostructures and Their Electronic,Optoelectronic Properties (Small 38/2017) 下载免费PDF全文
109.
Yueyue Wang Feifei Qin Junfeng Lu Jitao Li Zhu Zhu Qiuxiang Zhu Ye Zhu Zengliang Shi Chunxiang Xu 《Nano Research》2017,10(10):3447-3456
It is essential to develop a single mode operation and improve the performance of lasing in order to ensure practical applicability of microlasers and nanolasers.In this paper,two hexagonal microteeth with varied nanoscaled air-gaps of a ZnO microcomb are used to construct coupled whispering-gallery cavities.This is done to achieve a stable single mode lasing based on Vernier effect without requiring any complicated or sophisticated manipulation to achieve positioning with nanoscale precision.Optical gain and the corresponding ultraviolet lasing performance were improved greatly through coupling with localized surface plasmons of Pt nanoparticles.The ZnO/Pt hybrid microcavities achieved a seven-fold enhancement of intensity of single mode lasing with higher sidemode suppression ratio and lower threshold.The mechanism that led to this enhancement has been described in detail. 相似文献
110.
Glasses of the K2OZnOAl2O3SiO2 system co-doped with Eu2O3 and Yb2O3 were prepared by the melt-quenching technique. Transparent zincite (ZnO) glass–ceramics were obtained by secondary heat-treatments at 680–860 °C. At 860 °C, traces of Eu oxyapatite appeared in addition to ZnO nanocrystals. The average crystal size obtained from the X-ray diffraction data was found to range between 14 and 35 nm. Absorption spectra of the initial glasses are composed of an absorption edge and absorption bands due to electronic transitions of Eu3+ ions. With heat-treatment, the absorption edge pronouncedly shifts to the visible spectral range. The luminescence properties of the glass and glass-ceramics were studied by measuring their excitation and emission spectra at 300, 78, and 4.2 K. Strong red emission of Eu3+ ions dominated by the 5D0–7F2 (612 nm) electric dipole transition was detected. Changes in the luminescence properties of the Eu3+-related excitation and emission bands were observed after heat-treatments at 680 °C and 860 °C. The ZnO nanocrystals showed both broad luminescence (400–850 nm) and free-exciton emission near 3.3 eV at room temperature. The upconversion luminescence spectrum of the initial glass was obtained under excitation of the 976 nm laser source. 相似文献