【摘要】：汽車(chē)作為現(xiàn)代化的交通工具,給人們的生產(chǎn)與生活帶了極大方便,但同時(shí)有研究表明,汽車(chē)排放的氮氧化合物(NOx)、CO和碳水化合物(HCs)等污染物嚴(yán)重超標(biāo),其中產(chǎn)生的HCs是導(dǎo)致光化學(xué)煙霧的主要來(lái)源,極大危害人類(lèi)健康。因此,控制汽車(chē)排放污染,加強(qiáng)汽車(chē)尾氣污染防治技術(shù)研究,成為城市環(huán)境保護(hù)迫在眉睫的工作�；卺惙€(wěn)定性氧化鋯(Yttria-stablilzed zirconia,YSZ)固體電解質(zhì)氣敏傳感器由于能對(duì)汽車(chē)尾氣中HCs含量簡(jiǎn)便快速的實(shí)時(shí)監(jiān)測(cè),因而受到了廣泛的關(guān)注。由于敏感電極的形貌對(duì)YSZ基碳?xì)浠衔?HCs)傳感器的響應(yīng)性能影響較為明顯,本實(shí)驗(yàn)合成了數(shù)種不同納米形貌的NiO電極并對(duì)基于該類(lèi)電極的HCs傳感器的敏感性能做了一定的研究。實(shí)驗(yàn)以鋯基HCs傳感器為研究對(duì)象,利用水熱合成方法制備了七種不同形貌的NiO敏感電極材料,以Pt作為傳感器的參比電極材料,采用厚膜絲網(wǎng)印刷技術(shù)制備了YSZ基混合電位型HCs氣敏傳感器,對(duì)傳感器進(jìn)行了理化測(cè)試以及氣敏特性、響應(yīng)特性、穩(wěn)定性、氣相催化、選擇性、阻抗譜以及極化曲線測(cè)試。結(jié)果顯示:不同形貌NiO敏感電極傳感器在600℃取得最好的響應(yīng)性能,且各傳感器的響應(yīng)特性差別極大。在600℃、5 vol.%O2、100ppmC3H6下線性結(jié)構(gòu)NiO的氣相催化效率最低,進(jìn)而使得更多的待測(cè)氣體進(jìn)入其三相界面。線狀NiO敏感電極傳感器阻抗譜有最小的半圓弧,其低頻收縮度最大,反應(yīng)活化阻抗最小,進(jìn)而表現(xiàn)出最好的傳感器響應(yīng)性能。極化曲線測(cè)試得到的理論平衡電勢(shì)值和傳感器的實(shí)際測(cè)試值基本一致。在此基礎(chǔ)上,嘗試不同比例的YSZ摻雜商用顆粒狀形貌NiO作為混合電位型傳感器的敏感電極,并研究了摻雜對(duì)傳感器的性能影響機(jī)理。結(jié)果顯示:在600℃下,20%YSZ摻雜的NiO敏感電極傳感器具有最大的輸出電勢(shì)。鑒于錳系電極在600℃以下有很好的氣體惰性和穩(wěn)定性,實(shí)驗(yàn)制備了以Mn2O3為參比電極,以性能優(yōu)異的三種NiO材料作為敏感電極,制備了混合電位型傳感器,并研究了其敏感性能。測(cè)試結(jié)果顯示在550℃、5 vol.%O2、20-500 ppmC3H6條件下,三種類(lèi)型傳感器的階梯響應(yīng)性能和重復(fù)性良好,且三種傳感器在同種測(cè)試條件下響應(yīng)值差別顯著,其中線性NiO在550℃、100ppm C3H6下響應(yīng)值達(dá)到170mV。此外基于三種性能優(yōu)異的NiO敏感電極材料制備了YSZ基電流型HCs傳感器,并對(duì)傳感器的敏感性能、穩(wěn)定性以及選擇性進(jìn)行了測(cè)試。結(jié)果顯示在550℃下傳感器電流響應(yīng)值與待測(cè)氣體濃度呈現(xiàn)很好的線性關(guān)系,但是傳感器的長(zhǎng)期穩(wěn)定性有待進(jìn)一步提高。
[Abstract]:As a modern vehicle, automobile has brought great convenience to people's production and life. But at the same time, some studies have shown that the nitrogen oxide (NOx), CO) and carbohydrate (HCs) pollutants emitted by automobiles are seriously exceeding the standards. Among them, HCs is the main source of photochemical smog, which is harmful to human health. Therefore, it is an urgent task to control the automobile emission pollution and strengthen the prevention and control technology of automobile exhaust pollution. Based on yttrium stabilized zirconia (Yttria-stablilzed zirconia,YSZ) solid electrolyte gas sensor has attracted wide attention because of its simple and rapid real-time monitoring of HCs content in automobile exhaust. Because the morphology of the sensitive electrode has an obvious effect on the response performance of the YSZ based (HCs) sensor, several kinds of NiO electrodes with different nano-morphologies have been synthesized and the sensitivity of the HCs sensor based on this kind of electrode has been studied. Using zirconium based HCs sensor as the research object, seven kinds of NiO sensitive electrode materials with different morphologies were prepared by hydrothermal synthesis method. Pt was used as reference electrode material of the sensor. The YSZ based mixed potential HCs gas sensor was fabricated by thick film screen printing technique. The physical and chemical properties of the sensor, the gas sensing characteristics, the response characteristics, the stability, the gas phase catalysis, the selectivity, the impedance spectrum and the polarization curve were measured. The results show that the NiO sensor with different morphologies has the best response performance at 600 鈩，

本文編號(hào)：2265682