四苯基卟啉钴气敏元件的制备及性能

以四苯基卟啉为原料,制备了四苯基卟啉钴化合物,实现了对乙醇气体的检测,通过核磁1HNMR、场发射扫描电子显微镜(FE-SEM)、FTIR、UV-vis等对其进行了表征。利用旋转甩涂法制备了四苯基卟啉钴薄膜/K+交换玻璃光波导传感元件,并用其对多种气体进行了检测。结果表明:敏感元件对乙醇气体具有较好的选择性响应和较高的灵敏度,对乙醇的响应值分别是甲苯、氨气、甲醛气体响应值的2.24、3.32、6.8倍,响应时间和恢复时间分别为1.5 s和13 s,信噪比S/N=4.857;乙醇气体质量浓度为191 mg/m3时,相对标准偏差RSD=0.8%;敏感薄膜的平均厚度为(105±1)nm,平均折射率为1.750。在平行实验中,其结果也具有良好的线性关系(R2=0.992 4),表明该元件对乙醇气体检测的准确性。     

四羟基苯基锰卟啉的制备及其电化学性质研究

本文采用了优化路径分别合成出了四羟基苯基卟啉(THPP)和及其衍生物四羟基苯基锰卟啉(THPP-Mn)两种化合物,并对它们的结构与性能进行了表征。THPP和THPP-Mn在丙酮溶剂中的紫外可见光谱表明,相对于THPP,THPP-Mn的紫外可见光谱中的Soret带发生红移,吸收峰从419 nm移到476 nm,THPP-Mn的Q带吸收峰的个数减小,这是因为卟啉生成配合物后对称性增强而使吸收峰数目减少的缘故。电化学测试结果表明,四羟基苯基锰卟啉有一对明显的氧化还原峰,具有较好的氧化还原可逆性,并且随着扫描速率从10 mV/s增加到200 mV/s,其氧化峰从1.32 V逐渐增加到1.53 V,还原峰从0.94 V减少到0.74 V。因此,四羟基苯基锰卟啉具有较好的电化学性能,在储能材料领域具有很好的应用前景。     

四(3-甲氧基-4-羟基苯基)卟啉的合成与表征

用混合溶剂法合成了带有活性基团的四（3-甲氧基-4-羟基苯基）卟啉，考察了催化剂、溶剂的配比、反应温度、反应时间等因素对反应产率的影响，确定了合适的反应条件：V（丙酸）：V（冰醋酸）：V（硝基苯）=2：2：1；反应温度：120～140℃；反应时间：50-60min。还利用IR，UV—VIS，热分析。1HNMR数据对配合物的结构进行了表征。     

四苯基卟啉锶配合物的合成及发光性能

利用醋酸锶与四苯基卟啉反应,合成了四苯基卟啉锶配合物。利用元素分析、红外、核磁共振等对该配合物进行了结构表征。采用紫外-可见吸收光谱、荧光光谱和循环伏安法研究了该配合物的光电性能。四苯基卟啉锶配合物紫外-可见吸收光谱有一个强的吸收峰和一个次强的吸收峰,分别为428、457 nm。荧光光谱有一个强的发射峰和一个弱的发射峰,分别为610、676 nm。循环伏安法测得其氧化峰电位为1.558 V和1.051 V。与四苯基卟啉相比,四苯基卟啉锶紫外吸收发生红移,而荧光发射发生蓝移。     

聚合物键联钴卟啉的合成及其催化作用

合成了 5 -对羟苯基 - 1 0 ,1 5 ,2 0 -三 (对甲氧苯基 )卟啉 (1 )及其钴配合物 (2 )。将(1 )与氯甲基化聚苯乙烯树脂键合得聚合物键联卟啉 (3) ,(3)与钴离子络合得聚合物键联钴卟啉 (4) ,考察了 (4)对丙硫醇的催化氧化作用。对卟啉化合物进行了 IR、UV测定和元素分析。对丙硫醇氧化产物作了 HPL C、UV、IR和 MS分析。     

新型卟啉光敏剂:同分异构体空间结构与光敏活性

以2-硝基四苯基卟啉及其Cu（Ⅱ）、Ni（Ⅱ）配合物为原料,分别与1-萘酚、2-萘酚反应,合成了4对β-萘酚基四苯基卟啉同分异构体,并通过1HNMR、UV、IR、MS对新化合物进行了结构表征。比较了两类卟啉同分异构体作为光动力治疗光敏剂在光敏抗菌及光敏切割DNA方面的活性差异,并利用Chem3D软件的MM2分子力场计算方法确定了卟啉同分异构体的空间优势结构。结果表明,β-萘酚基四苯基卟啉同分异构体空间结构的非平面程度相当,光敏活性差异也不明显,卟啉的非平面性与光敏活性具有一定的一致性。     

反相高效液相色谱法测定meso-四苯基卟啉钴的纯度

采用反相高效液相色谱法测定合成meso-四苯基卟啉钴的纯度;以甲醇乙腈二氯甲烷(体积比为55∶35∶10)为流动相,ShimpackCLCODS柱(150mm×6.0mmi.d,5μm)为分离柱,流速为1.5mL/min,检测波长420nm;meso四苯基卟啉钴的测定在1.0～10μg/mL时线性关系良好(相关系数r=0.9993),加标回收率为97.03%～101.42%,重复进样的相对标准偏差RSD为0.64%～2.92%(n=5)。方法的准确度高,精密度好,实际应用效果好。     

meso—四（2—氨基—5—横酸苯基）卟啉的合成及其与钴显色反应的研究

研究了新水溶性ｍｅｓｏ－四（２－氨基－５－磺酸苯基）卟啉的合成，提出以冰乙酸乙酸酐代替常用的丙酸作介质，所得ｍｅｓｏ－四（２－硝基苯基）卟啉为紫蓝色片状晶体，再将其还原和横化得标题试剂，还研究了度剂干氨性介质中，在Ｐｂ（Ⅱ）存在下与钴（Ⅱ）的显角反应，钴的二元配合物的最大吸收波长为４２９ｎｍ，表观摩尔吸光系数为１．５０＊１０＾５。可用于维生素Ｂ１２注射液中痕量钴的测定。     

金属卟啉负载炭黑电催化剂氧还原性能

合成了四甲氧基苯基钴卟啉（CoTMPP）和四甲氧基苯基铁卟啉（FeTMPP）配合物,分别负载于经过双氧水和硝酸预处理且掺杂了MnO_x的炭载体,用于质子交换膜燃料电池阴极氧还原反应电催化剂.讨论了不同中心金属离子、不同载体、不同预处理方法和不同焙烧温度对催化剂催化活性的影响.通过旋转圆盘电极技术（RDE）和紫外可见光谱（UV-vis）测试,利用循环伏安曲线（CV）和Koutevky-Levich关系式评价了电催化剂对氧还原反应的电催化性能.研究表明,CoTMPP负载于双氧水处理过的炭载体BP 2000上活性最好,焙烧的最佳温度是900℃,同时发现在载体中掺杂MnO_x并没有达到预期效果.     

卟啉与金属卟啉的光电导性能研究

以苯甲醛和吡咯为原料,丙酸和硝基苯为溶剂,合成了四苯基卟啉(TPP),收率达29.8%。TPP与金属ZnCo、Mn盐合成相应的金属卟啉配合物,收率>90%。用核磁和质谱对化合物结构进行了表征。紫外-可见吸收光谱分析结果表明,TPP有强的Soret吸收带和四个Q带,形成金属卟啉后,Q带减少至两个,且Soret带红移。X射线衍射光谱分析显示,TPP和四苯基金属卟啉粉末均有较高的结晶度。分别以这些卟啉化合物为电荷产生材料,制备了功能分离型双层光电导体,并对它们的光电导性能进行了研究。结果表明,四苯基锌、钴卟啉配合物的光敏性明显优于TPP,其光敏度(E2/3)分别为11和10lx·s。     

Facile fabrication and superior gas sensing properties of spongelike Co-doped ZnO microspheres for ethanol sensors

In this work, a novel strategy has been adopted for the synthesis of hybrid Co-doped ZnO (Co/ZnO) microspheres using the solvothermal method with a synergistic effect of ultrasonic and microwave radiation. The Co/ZnO microspheres were characterized by XRD, FE-SEM, XPS and BET techniques. Sensing tests revealed that the Co/ZnO microspheres exhibited highly better ethanol sensing properties than pure ZnO nanoparticles did, including lower limit of detection (less than 10?ppm), higher response (ca. 120–100?ppm ethanol), lower operating temperature (ca. 220?°C), faster response (10?s) and recovery time (5?s) and better selectivity. The superior gas sensing properties were mainly attributed to the incorporation of Co, which increased the amount of oxygen vacancies and adsorbed oxygen. The sensing mechanism has been explained by oxygen chemisorption on the ZnO surfaces and subsequent reactions of surface adsorbed oxygen species with the ethanol molecules.     

硼掺杂Co3O4海胆状微球的制备及其乙醇气敏强化机制

四氧化三钴（Co₃O₄）是一种p型半导体,可作为气体传感材料。非金属硼（B）具有吸电子特性,将其与p型半导体气敏材料进行掺杂,可增加材料的空穴载流子浓度,从而提高材料的气敏性能。本文以六水合硝酸钴[Co(NO₃)₂·6H₂O]、硼酸（H₃BO₃）和尿素[CO(NH₂)₂]为原料,采用低温一步水热法成功制备了B掺杂Co₃O₄海胆状微球。通过X射线衍射仪（XRD）、扫描电镜（SEM）、透射电镜（TEM）、X射线光电子能谱仪（XPS）和拉曼光谱仪（Raman）对掺杂B前后的Co₃O₄进行结构表征,探究B掺杂对其气敏性能的影响。结果表明：B掺杂对Co₃O₄材料的气敏性能有明显的强化作用。当掺杂摩尔比为Co∶B=8∶1时,B-Co₃O₄对1×10⁵μg/L乙醇的最佳工作温度为180℃,灵敏度响应达到26.8,是相同条件下纯Co₃O₄的4.4倍。B-Co₃O₄在较低的工作温度下,具有良好的灵敏度、选择性和稳定性,是一种性能优良的气敏材料。     

新试剂2－（6－甲基－2－苯并噻唑偶氮）－5－二乙氨基酚反相高效液相色谱快速分析钌、铑、钯和钴

报道了以新试剂２－（６－甲基－２－苯并噻唑偶氮）－５－二乙氨基酚（ＭＢＴＡＥ）作柱前衍生化试剂，反相高效液相色谱分离并测定轻铂族元素钌（Ⅲ）、铑（Ⅲ）和钯（Ⅱ）以及过渡元素钴（Ⅱ）。各金属离子的检出限分别为（ｎｇ／ｍＬ）：Ｒｕ１．６０，Ｒｈ０．４７，Ｐｄ０．１２，Ｃｏ０．１５。此方法分离贵金属具有分析时间短，灵敏度高等优点。     

Hydrothermal synthesis of CuO/rGO nanosheets for enhanced gas sensing properties of ethanol

In this work, CuO nanosheets and CuO/rGO nanocomposites are synthesized by one-step hydrothermal method and characterized accordingly. Next, these samples are tested for gas sensing performance. The test data show that the CuO/rGO sensors have significantly improved gas sensing performance for ethanol compared to the pure CuO sensor. It should be noted that the CuO/rGO-10 sensor has the most outstanding gas sensing performance among the four sensors prepared, with an optimum working temperature 25 lower than that before doping, and its response value for 100 ppm ethanol at 175 °C is 10.54, which is 3.75 times higher than that before rGO doping. Also, the CuO/rGO-10 sensor has remarkable selectivity and reproducibility for ethanol. Most importantly, its limit of detection for ethanol is 100 ppb. At last, the gas sensing mechanism of the composites for ethanol is explained. Enhanced gas sensing performance of CuO/rGO sensors for ethanol is attributed to the lamellar structure and the synergistic effect between CuO and rGO.     

Au nanoparticle modified single-crystalline p-type LaRhO3/SrTiO3 heterostructure for high performing VOCs sensor

Since the discovery of two-dimensional electron gas (2DEG) confined at perovskite LaAlO₃/SrTiO₃ (LAO/STO) interface, extensive efforts have been devoted to explore novel high-performance all oxide electronic devices, including gas sensors. Among perovskite oxides, LaRhO₃ (LRO) possesses unique p-type conductivity and catalytic properties, which offer promising benefits for sensing volatile organic compounds (VOCs) molecules. In this work, single-crystalline p-type LRO thin film was epitaxially grown on STO (110) substrate as a high-quality sensing channel. Drastic improvement of sensing performance of LRO probed by 50 ppm ethanol was accomplished by appropriate Au decoration layer, e.g., an increased response (from 2.5 to 8.4), reduced optimal operation temperature (from 325 to 275 °C), decrease of response/recovery time (from 100/85 to 54/23 s) and improvement of detection limit (from 5000 to 250 ppb). X-ray photoelectron spectroscopy (XPS) indicates that Au nanoparticles facilitates the formation of reactive chemisorbed oxygen species, which substantially trigger the charge exchange occurring at ethanol/LRO interface. Our work highlights the importance of surface engineering toward high-performance perovskite based VOCs sensors.     

Low concentration ethanol sensor based on graphene/ZnO nanowires

Metal-oxide based gas sensors are widely used as the gas sensing elements in industrial and residential areas. Many efforts have been made to increase sensitivity and reduce the working temperature of metal-oxide based gas sensors. In this paper, ZnO nanowires (NWs) were successfully grown on graphene (Gr) nanosheets by the hydrothermal method. The synthesized Gr/ZnO NWs nanocomposite were investigated as the sensing material. Not only is the sensor response much higher, it also works in a lower working temperature toward a low concentration of ethanol in comparison with pure ZnO NWs. The optimum working temperature is reduced from 200 °C in pure ZnO NWs to 125 in Gr/ZnO NWs sensor. The maximum response of the Gr/ZnO NWs sensor is 26, which is approximately enhanced twice as much as the pure ZnO NWs sensor. The lower limit of detection (LLOD) of the proposed sensor is as low as 1 ppm ethanol vapor. The sensor was shown a high response, good selectivity, fast response toward ethanol vapor, excellent repeatability, and low sensitivity toward a high relative humidity, as well as remarkable long-term stability.     

水热法制备稀土元素掺杂二氧化锡及其对乙醇气敏性能

利用水热法制备了SnO2粉末及掺杂不同稀土离子的SnO2粉末. 通过XRD和气敏测试仪对其结构和性能进行了表征和测试. 结果表明,所制备的SnO2粉末呈四方金红石结构,稀土离子的掺入并没有改变SnO2的晶体结构,也无新晶相的出现. 掺杂镧的SnO2样品(SnO2:La)对乙醇有较高的气敏性. 分析了气敏机理. SnO2:La的灵敏度随着乙醇浓度的增加而增加,随温度的升高呈现波动状,且当温度在250℃时,SnO2:La对1.00′10-4乙醇的灵敏度最大,可达到101.1. 在此条件下其响应时间和恢复时间约为5 s.     

光波导二氧化氮气敏传感元件的研究

本文用离子交换法制备K+交换玻璃光波导元件,并在其表面固定纳米级敏感层酞菁铜(CuPc)薄膜,利用光波导气体检测系统对NO2气体进行测试.结果表明,该传感元件常温下对NO2等气体有快速、可逆的响应,并具有重现性好,灵敏度高等特点.     

用于气体传感器的碳复合NiO敏感材料

二甲苯是工业生产中关键的化工原料，可用于生产油墨、涂料等，是一种典型的挥发性有机化合物。作为燃料、油漆的常用稀释剂，工业生产的常用溶剂，生活及生产过程中都避免不了与二甲苯进行接触。这种典型的挥发性有机化合物含量一旦接触超标就会对人类的身体健康造成威胁，因此二甲苯气体的检测很有必要。目前，许多金属氧化物半导体和碳材料都被认为是有潜力的气体传感材料，但是由于对传感器的性能要求会不断提高，研究新型的气体传感材料尤为重要。碳材料如石墨烯、碳纳米材料出现后，为敏感材料的研发开辟了新的方向。本文采用水热反应法成功合成出了荧光碳纳米材料复合的NiO，并研究了材料的传感性能。结果表明材料对二甲苯具有良好的响应，紫外光激发及最佳工作温度条件下对1.3μL/L二甲苯灵敏度可以达到2.9，检测下限可以达到0.215μL/L，对SO₂、丙酮、甲苯、甲醛等干扰气体具有选择性，响应时间29s，恢复时间31s。     

One-step room-temperature solid-phase synthesis of ZnFe2O4 nanomaterials and its excellent gas-sensing property

ZnFe₂O₄ nanomaterials have been synthesized by simple one-step solid-phase chemical reaction between Zn(CH₃COO)₂·2H₂O, FeCl₃·9H₂O and NaOH within a very short time at room temperature. The solid-phase products were characterized by X-ray diffraction, energy-dispersive X-ray spectroscopy, thermogravimetic analysis, transmission electron microscopy and scanning electron microscopy. Results indicated that the particle size of product can be obviously let up and the agglomeration phenomenon can be improved by the surfactant. Moreover, the ZnFe₂O₄ nanomaterials were applied in gas sensor and exhibited much better sensing performance than bulk ZnFe₂O₄. The as-prepared ZnFe₂O₄ nanomaterials have high sensitivity, good selectivity and fast response/recovery characteristic for ethanol and hydrogen sulfide. The improved ZnFe₂O₄ nanomaterials have high response value of 21.5 and 14.8 for ethanol and hydrogen sulfide in the optimized operating temperature of 332 °C and 240 °C, respectively. The response and recovery time was found to be within 4 s and 14 s for ethanol, while 7 s and 25 s for hydrogen sulfide.