Poly(alkoxy-bithiophenes) sensors for organic vapours
Poly(alkoxy-bithiophenes) sensors for organic vapours
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DOI：
10.1016/s0925-4005(02)00323-4
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发表时间：
2003-01-15
影响因子：
8.4
通讯作者：
Montoneri, E
中科院分区：
文献类型：
--
作者：
Gallazzi, MC;Tassoni, L;Montoneri, E
本工作报道了由掺杂FeCl3、Fe(ClO4)(3)或CuCl2的聚(3，3‘-二戊氧基-2，2’-联噻吩基)(I)或poly[3，3‘-2-(2-ethoxy)ethoxy-2，2’-bithiophene](II)制成的传感器的电阻测量和在线UV-VIS-NIR光谱，并在50-66,444 ppm(v/v)的Ar中测试了邻二甲苯、正丁醇、苯、甲醇、正庚烷和3-戊酮的蒸气。每个传感器在长达41次和25天的时间里，在广泛的浓度范围内重复和随机地暴露在测试蒸汽中。在测试蒸汽注入之间执行整齐的Ar扫描，以恢复基线条件并测试传感器的可逆性。电阻相对于曝光前测量值的百分比变化，以及传感器吸光度在880-1400运行时的百分比变化，都随着所用浓度的不同而线性变化。灵敏度α是通过对总共约400次测量的80组Deltar、C值的线性回归分析计算出来的，以评估几个参数的影响，即传感器的化学性质、制造、暴露在测试蒸汽中的时间以及在空气中的老化。数据分析表明，灵敏度取决于传感器和测试蒸汽的化学性质以及暴露的时间长短。在90 S暴露下收集的数据给出了较窄的标准偏差值范围，在最坏的情况下相当于计算阿尔法值的14%，而在传感器和测试蒸汽组合的范围内，阿尔法值变化从3.4x10(-5)(碘掺杂三氯化铁与甲醇)到231x10(-5)(碘掺杂Fe(ClO4)(3)与邻二甲苯)。在最长工作时间观察到显著的基线漂移，但这并未被证明影响传感器的灵敏度。传感器和电子光谱的伴随变化为进一步研究传感器-测试蒸汽相互作用的性质提供了耐人寻味的范围。(C)2002 Elsevier Science B.V.保留所有权利。
This work reports electrical resistance measurements and on line UV-Vis-NIR spectra for sensors, fabricated from poly(3,3'-dipentoxy-2,2'-bithiophene) (I) or poly[3,3'-2-(2-ethoxy)ethoxy-2,2'-bithiophene] (II) doped with FeCl3, Fe(ClO4)(3), or CuCl2, and tested against vapours of o-xylene, n-butanol, benzene, methanol, n-heptane, and 3-pentanone over a 50-66,444 ppm (v/v) concentration range in argon. Each sensor was exposed repeatedly and randomly to the test vapours in a wide concentration range over a maximum of 41 times and 25 days. Neat argon sweeping was performed between test vapour injections to recover base line conditions and test sensor reversibility. The percentage changes of electrical resistance, relative to the value measured before exposure, and of the sensor absorbance at 880-1400 run, both varied linearly according to the concentration used. The sensitivities alpha were calculated from the linear regression analysis of 80 sets of DeltaR, C values for a total of about 400 measurements, in order to assess the influence of several parameters, i.e. the chemical nature of the sensor, the fabrication, the exposure time to the test vapour, and the ageing in air. The data analysis demonstrated that sensitivity depends on the chemical nature of both the sensor and the test vapour and on the length of exposure. Data collected with a 90 s exposure gave the narrower range of standard deviation values, amounting to 14% of the calculated alpha value in the worst case, whereas alpha values over the range of sensor and test vapour combinations varied from 3.4 x 10(-5) for I doped FeCl3 versus MeOH to 231 x 10(-5) for I doped with Fe(ClO4)(3) versus o-xylene. A significant base line drift was observed at the longest working time, but it was not proven to affect the sensitivity of the sensor. The concomitant changes of the sensors and of the electronic spectra offer intriguing scope to further investigate the nature of the sensor-test vapour interaction. (C) 2002 Elsevier Science B.V. All rights reserved.