射频反应磁控溅射掺杂MWCNTs的SnO2薄膜NO2气敏传感器的研究

采用射频反应磁控溅射方法制备了氧化锡/多壁碳纳米管（SnO2/MWCNTs）薄膜材料,并在此基础上研制NO2气敏传感器。采用X射线衍射仪（XRD）、X光电子能谱仪（XPS）、扫描电子显微镜（SEM）来研究WO3/MWCNTs材料的表面形貌、表面化学状态、表面化学元素等材料特性,研究结果表明MWCNTs已经掺杂进SnO2材料,合成的SnO2/MWCNTs气敏传感器表现出对低浓度（甚至低于10ppb）的NO2气体有较高的灵敏度和较好的反应-恢复特性,并解释了该传感器的工作机理是基于pn结（P型MWCNTs和N型SnO2)作用的结果。     

掺SiO_2的WO_3纳米粉体的合成及其NO_2气敏特性

采用sol-gel法制备了一系列掺有SiO2的WO3纳米粉体,通过X射线衍射仪、透射电镜等测试手段分析了材料的微观结构,测试了材料的气敏性能,探讨了煅烧温度、掺杂量、工作温度等对材料气敏性能的影响。研究发现:适量SiO2的掺杂有利于提高WO3对NO2气体的灵敏度,其中SiO2掺杂量为3%(质量分数)的气敏元件,在150℃工作温度下,灵敏度达713,响应–恢复时间分别为7s与26s。对WO3的NO2气敏机理也进行了探讨。     

TiO_2-WO_3纳米粉体的制备及氨敏性能研究

采用共沉淀法制得了w(TiO2)为0~10%的TiO2-WO3纳米粉体材料,利用X射线衍射仪、透射电镜等测试手段,分析了材料的微观结构,探讨了烧结温度、掺杂量、工作温度对WO3粉体材料气敏性能的影响。研究发现:TiO2的掺杂抑制了WO3晶粒的生长,提高了WO3粉体材料对氨气的灵敏度,其中,w(TiO2)为1%的烧结型气敏元件,在250~280℃的温度范围内,对氨有较高的灵敏度和较好的响应–恢复特性,并对其氨敏机理进行了探讨。     

微波辅助合成纳米WO_3/TiO_2复合材料及其气敏性能

为改善WO3基敏感材料的气敏性能,采用微波回流法一次性合成了纳米WO3/TiO2复合材料,并研究TiO2掺杂量对用其制备的气敏元件气敏性能的影响。结果表明:此气敏元件对体积分数为100×10-6的NOx、二甲苯、H2S和丙酮气体具有较强的敏感性,掺杂w(TiO2)为20%的元件,对H2S和NOx的灵敏度分别为31.18和695.84;掺杂w(TiO2)为30%的元件,对二甲苯和丙酮的灵敏度分别为39.19和35.69。     

聚噻吩/WO_3复合纳米材料的制备及气敏性能

采用水合肼法制备WO3粉体,再以无水FeCl3作氧化剂,通过原位化学氧化聚合制备了不同聚噻吩(PTh)掺杂量的PTh/WO3复合纳米材料。并研究了用其制备的气敏元件的气敏性能。结果表明:气敏元件对H2S和NOx有较高的灵敏度和较好的选择性。用质量分数w(PTh)为5%的PTh/WO3复合纳米材料制备的气敏元件,在加热电压为2.25V时,对体积分数φ(NOx)为5×10–6的灵敏度可达77.14;用w(PTh)为20%的PTh/WO3复合纳米材料所制之气敏元件,在加热电压为2.43V时,对φ(H2S)为20×10–6的灵敏度达63.27。     

水热法制备Co掺杂WO_3气敏材料及其性能研究

采用水热法合成了Co掺杂的纳米WO3气敏材料,研究了不同含量Co掺杂的WO3气敏材料的气敏性能以及环境湿度对其性能的影响。结果表明,少量Co掺杂可以提高WO3的气敏性能,Co掺杂量为质量分数0.8%的WO3基气敏元件对H2S和NOx具有很好的选择性,灵敏度分别高达183.214和1 619.726,并且该元件具有很好的抗湿性。     

掺Sm~(3+)的WO_3纳米粉体的制备及其NO_2气敏性能

通过固相研磨法制得了一系列掺有Sm3+的WO3纳米粉体,利用XRD、TEM等测试手段,对其物相﹑结构进行了表征。结果表明:掺Sm3+的WO3纳米粉体结晶良好,平均粒径为50nm。利用该纳米粉体制成气敏元件,并采用静态配气法测试了元件的气敏性能。研究发现:当掺杂x(Sm3+)=0.5%时,元件在160℃下对体积分数为30×10-6的NO2气体的灵敏度高达169,响应时间为8s,是一种较为理想的低温NO2气敏元件。     

溶胶–凝胶法WO_3纳米粉体的气敏性能研究

采用溶胶–凝胶法制得了不同掺杂量的TiO2-WO3(TiO2质量分数为0~5%)纳米粉体材料,利用X射线衍射仪、透射电镜等测试手段分析了材料的微观结构,并进行了气敏性能测试。研究发现:适量TiO2的掺杂可改变WO3的晶型,抑制晶粒的生长,提高粉体材料的气敏性能,其中掺杂量为3%的烧结型气敏元件在220℃时对汽油有较高的灵敏度,线性检测范围较宽,且抗干扰能力强。     

WO3的气敏特性研究

通过实验,结合气敏元件分析方法,对WO3气敏元件的气敏特性、响应与恢复时间、电阻特性、初期驰豫特性进行了系统分析。为进一步开发研制WO3气敏元件提供了可靠的数据。     

气敏元件室温光激发气敏性能研究

研究了WO3掺杂的ZnO基气敏元件在紫外(UV)光激发下,对乙醇气体的室温气敏性能。结果表明:在UV光照射下,各元件在室温下对体积分数为100×10–6的乙醇气体显示了很好的光敏、气敏性能,响应、恢复时间均在8s以内,其中以掺杂X(WO3)为1%的元件W(1)为最佳,从而实现了室温下的气敏测试。     

Highly enhanced photoelectric catalysis of WO3 nanoblocks loaded with Ag nanoparticles

WO3/Ag composite film photoanodes were synthesized by hydrothermal combined electrodeposition method. Characterization of samples was conducted by scanning electron microscope (SEM) and X-ray diffraction (XRD), which showed that WO3/Ag composite films had been synthesized. Diffuse reflectance spectra show WO3/Ag composite film has more strong absorption than WO3 film under simulated visible light irradiation. Electrochemical impedance spectroscopy shows WO3/Ag composite film photoanode enhances charge transfer efficiency compared with WO3 film. WO3/Ag composite film photoanodes show higher photocurrent and photoelectric catalytic activity than WO3 film, and the WO3/Ag composite film obtained by depositing Ag nanoparticles at 50 s (WO3/Ag-50) shows the highest photocurrent and photoelectric photoelectric catalytic activity. Meanwhile, the photoelectric catalytic activity of the composite film is higher than their direct photocatalytic and electric catalytic activity. The higher photocurrent and photoelectric catalytic activity of the WO3/Ag composite film photoanodes are attributed to the surface plasmon resonance effect of Ag nanoparticles and Schottky junction effect at the WO3/Ag interface.     

Electrochromism and photoelectrochemical perfor- mance of WO3/Au composite film electrodes

WO3/Au composite film electrode was prepared by hydrothermal combined electrodeposition method. The samples were characterized by scanning electron microscope (SEM), energy dispersive spectrometer (EDS) and X-ray diffraction (XRD), and the results showed that WO3/Au composite film was synthesized. Electrochemical and spectral measurements were carried out to obtain the electrochromic response time, reversibility, coloration efficiency (CE) and transmittance of the WO3/Au composite film. The photoelectrochemical properties of the samples were characterized by measuring photocurrent and photocatalytic degradation efficiency. The results show that compared with pure WO3 nanoblocks, WO3/Au composite film improves the electrochromic property, photocurrent and photoelectric catalysis activity. Among them, WO3/Au composite film prepared by depositing Au nanoparticles in 80 s showed the highest electrochromic property, photocurrent and photoelectric catalysis activity. Meanwhile, compared with direct photocatalysis (DP) and electrocatalysis (EC), the photoelectrocatalysis (PEC) activity of the composite film is the highest.     

溶胶-凝胶法制备氧化钨薄膜的研究

本文以钨酸盐为原料利用溶胶凝胶法,在陶瓷衬底制备WO3敏感薄膜,于500℃退火。接着对制备好的薄膜进行X射线衍射与电子显微测试,观察到薄膜表面呈较规则的纳米多孔结构。接着对NO2、H2、乙醇等气体进行敏感测试,测试证明薄膜对H2、乙醇敏感性较差,对NO2敏感性良好。     

具有新型电荷产生层的叠层有机发光器件

研究了采用薄层WO3作为叠层有机发光器件电荷产生层时的性能并对其厚度进行了优化,器件的电荷产生层由Li掺杂的电子注入层和高透明的WO3组成.研究表明,薄层WO3具有很高的透明度,并能有效地产生和注入空穴.叠层器件性能与单发光单元器件相比较,其亮度及效率均有大幅提高,叠层器件的最大电流效率达到了4.2 cd/A,在相同的电流密度下,叠层器件的效率约为传统器件的2倍;同时,电荷产生层的性能与WO3薄膜厚度密切相关,WO3薄膜厚度为3 nm时,器件的效率在整个电流范围内都保持稳定.采用薄层WO3作为电荷产生层为制备高效叠层有机发光器件提供了一条有效的途径.     

磁控溅射法制备WO_3薄膜及其氢敏特性研究

采用直流反应磁控溅射法,在未抛光的Al2O3基片上制备WO3薄膜,在干燥空气中经过热处理;利用SEM观察薄膜表面形貌;通过XRD测量,对薄膜的晶体结构进行分析;薄膜氢敏特性测试采用静态配气法。经过400℃热处理,当工作温度在270℃时,对体积分数为3×10-4%H2的灵敏度达到了77,稳定性较高、选择性好、响应时间在15s以内。WO3薄膜是一种较理想的氢敏材料,在氢敏传感器的设计中必定会得到足够的重视和广泛应用。     

掺铂WO3-SiO2复合薄膜结构表征和气致变色性能研究

采用溶胶－凝胶法制备WO3－SiO2复合薄膜,对不同温度热处理的复合薄膜及单一组分薄膜的结构和气致变色性能进行了对比分析。XRD分析结果表明,复合薄膜的晶化温度提高、晶化程度降低,存在一定的晶格畸变;IR分析结果表明,在热处理过程中复合薄膜氧化钨分子间不易缩合,分子结构对称性低、变形多。性能测试结果表明,在复合薄膜中,WO3与SiO2之间的相界等结构缺陷为氢气提供扩散通道,使复合薄膜在热处理后气致变色性能优于单一组分薄膜。     

sol-gel法制备WO_3电致变色薄膜的工艺研究

采用sol-gel法制备了WO3电致变色薄膜,通过工艺参数的优化,对WO3薄膜的电致变色性能、表面结构和物相进行比较研究。结果表明:陈化3d的前驱体溶液,以5cm/min的提拉速度在ITO导电玻璃基体上镀膜,经250℃保温60min热处理的薄膜在着色态、褪色态下的透射率之差达到50%以上,电致变色可逆性能较好。     

射频磁控溅射制备非晶WO3薄膜的结构及其光电性质研究

采用射频磁控溅射技术,以WO3陶瓷靶为原料,在透明导电氧化铟锡（ITO）玻璃上沉积了非晶相WO3薄膜,研究了溅射功率对薄膜结构及光学性质的影响,并研究了WO3薄膜的电致变色特性。利用扫描电子显微镜（SEM）、X射线衍射技术（XRD）表征了薄膜的表面形貌和内部结构;利用UV-Vis分光光度计表征了薄膜在变色前后的光学透过性质,利用电化学测试工作站研究了WO3薄膜的电致变色性质,并从原理上分析了WO3薄膜的变色机理。研究结果表明,不同功率下获得的WO3薄膜均为非晶结构,在可见光范围内有较高的透过率。透明的WO3薄膜在负向电压下逐渐转变成深蓝色,且在撤去电压后其颜色不变,当施加正向电压时,薄膜又转换为透明态,表现出良好的电致变色特性。所制备WO3薄膜在550nm处褪色态的透过率为83%,着色态的透过率为29%,使得该薄膜在智能窗方面具有广阔的应用前景。     

sol-gel法制备WO_3电致变色薄膜的研究

采用正交实验设计方法,优化了钨粉过氧化聚钨酸sol-gel法制备WO3薄膜的配方,并且通过测定薄膜的物相结构、光透过率和循环伏安特性等研究了薄膜的电致变色性能。结果表明,制备WO3薄膜的最优配方为:钨粉(纯度为99.5%)6g、浓双氧水20mL、无水乙醇22mL、冰醋酸6mL。该配方所制备的薄膜具有非晶态结构,且薄膜在着色态、褪色态下的透过率之差达到50%以上。     

The Synergistic Effect of Prussian‐Blue‐Grafted Carbon Nanotube/Poly(4‐vinylpyridine) Composites for Amperometric Sensing

Because of its high activity and selectivity toward the reduction of hydrogen peroxide and oxygen, Prussian blue (PB) is usually considered as an “artificial enzyme peroxidase” and has been extensively used in the construction of electrochemical biosensors. In this study, we report on the construction of amperometric biosensors via grafting PB nanoparticles on the polymeric matrix of multiwalled carbon nanotubes (MWCNTs) and poly(4‐vinylpyridine) (PVP). The MWCNT/PVP/PB composite films were synthesized by casting films of MWCNTs wrapped with PVP on gold electrodes followed by electrochemical deposition of PB on the MWCNT/PVP matrix. The electrode modified with the MWCNT/PVP/PB composite film shows prominent electrocatalytic activity toward the reduction of hydrogen peroxide, which can be explained by the remarkable synergistic effect of the MWCNTs and PB. Therefore, fast amperometric response of this sensor to hydrogen peroxide was observed with a detection sensitivity of 1.3 μA μM ^–1 of H₂O₂ per square centimeter area and a detection limit of 25 nM . These results are much better than those reported for PB‐based amperometric sensors. In addition, a glucose biosensor fabricated by casting an additional glucose oxidase (GOD) containing Nafion film above the MWCNT/PVP/PB composite film shows promise for the sensitive and fast detection of glucose. The observed high stability, high sensitivity, and high reproducibility of the MWCNT/PVP/PB composite films make them promising for the reliable and durable detection of hydrogen peroxide and glucose.