【摘要】：氯鹽是引起鋼筋混凝土結(jié)構(gòu)腐蝕的最主要因素,因此準(zhǔn)確檢測其內(nèi)氯離子濃度具有重要的意義。傳統(tǒng)的取樣檢測方法對混凝土結(jié)構(gòu)本身產(chǎn)生損壞,且工作量大、操作繁瑣,而埋入式氯離子傳感器因電極壽命短、抗污染能力差也受到限制。本文以銀箔為基體制備了卷壓式Ag/AgCl電極,同時采用熱壓法制備了粉壓型Ag/AgCl電極以及粉壓型MnO2參比電極。實(shí)驗(yàn)結(jié)果表明,電極具有較好的電化學(xué)響應(yīng)特性曲線,適用于混凝土內(nèi)氯離子含量的檢測。本文首先通過恒電流氧化法制備了卷壓式Ag/AgCl電極,并測試了其在模擬孔溶液中的響應(yīng),電極在溶液中浸泡230d內(nèi)電位波動小于6mV,具有較接近理論值的線性響應(yīng)斜率,且腐蝕電流密度大,具有一定的抗污染能力。SEM形貌分析表明:卷壓方式不僅增加了電極的活性比表面積,提高電極的穩(wěn)定性與反應(yīng)活性;同時,借助AgCl/Ag的多層堆疊,增強(qiáng)了顆粒與基體間的附著力,提高Cl-離子檢測的可靠性及電極使用壽命。其次,對混凝土半透膜、堿性凝膠電解質(zhì)、錳環(huán)體三部分進(jìn)行了電化學(xué)測試并組裝制備MnO2參比電極。結(jié)果顯示,β-MnO2電化學(xué)活性更高,自制凝膠電解質(zhì)的保水性和導(dǎo)電性良好,采用膨脹劑制備的混凝土半透膜電阻最小,MnO2電極埋置于混凝土中穩(wěn)定性良好,有一定的抗極化能力。本文還將卷壓式Ag/AgCl電極表面包裹含聚乙烯醇凝膠電解質(zhì)的無紡布,并將其埋置于混凝土中,其養(yǎng)護(hù)齡期內(nèi)電位穩(wěn)定性良好,電位與Log[Cl-]呈較好的線性度。在內(nèi)摻低濃度的硫離子及胺類緩蝕劑情況下,電位漂移不大,表明其抗干擾能力強(qiáng)。與化學(xué)分析法相比,卷壓式電極所檢測的氯離子濃度偏小,但可通過誤差系數(shù)修正。本文最后還采用碳納米管(CNTs)與Ag/AgCl制備了碳基復(fù)合電極傳感器,發(fā)現(xiàn)Ag/AgCl/CNTs在溶液浸泡60d內(nèi)電位穩(wěn)定性依然較好,其線性響應(yīng)斜率為49.91mV,且具有較小的電荷傳遞電阻及較大的腐蝕電流密度,是一種有希望的混凝土Cl-濃度監(jiān)測傳感器。
[Abstract]:Chloride salt is the most important factor to cause corrosion of reinforced concrete structure, so it is very important to accurately detect the concentration of chloride ion in reinforced concrete structure. The traditional sampling and detection methods have caused damage to the concrete structure itself, and the workload is large and the operation is cumbersome. However, because of the short electrode life, the poor anti-pollution ability of the embedded chlorine ion sensor is also limited. In this paper, the rolled Ag/AgCl electrode was prepared with silver foil as the substrate, and the powder pressed Ag/AgCl electrode and the powdered MnO2 reference electrode were prepared by hot pressing method. The experimental results show that the electrode has a good electrochemical response curve and is suitable for the detection of chloride ion content in concrete. In this paper, the coil type Ag/AgCl electrode was prepared by constant current oxidation method, and its response in simulated pore solution was measured. The potential fluctuation was less than 6 MV within 230 days after immersion in the solution, which showed a linear response slope close to the theoretical value. Moreover, the corrosion current density is high, and it has some anti-pollution ability. SEM morphology analysis shows that the coiling method not only increases the specific surface area of the electrode, but also improves the stability and reaction activity of the electrode, at the same time, with the help of the multilayer stacking of AgCl/Ag, The adhesion between particles and matrix was enhanced, and the reliability of Cl- ion detection and the lifetime of electrode were improved. Secondly, the MnO2 reference electrode was prepared by electrochemical measurement on the three parts of semi-permeable concrete membrane, alkaline gel electrolyte and manganese ring. The results show that the electrochemical activity of 尾 -MnO2 is higher, the water retention and electrical conductivity of self-made gel electrolyte are good, and the semi-permeable film resistance of concrete prepared with dilatant has good stability and polarization resistance. In this paper, the non-woven fabric containing polyvinyl alcohol gel electrolyte is coated on the surface of the rolled Ag/AgCl electrode and buried in concrete. The potential has good stability during curing period, and the potential has a good linearity with Log [Cl-]. Under the condition of low concentration of sulfur ion and amine inhibitor, the potential drift is small, which indicates that its anti-interference ability is strong. Compared with the chemical analysis method, the chloride concentration detected by the coil electrode is smaller, but can be corrected by error coefficient. Finally, carbon nanotube (CNTs) and Ag/AgCl were used to fabricate the carbon based composite electrode sensor. It was found that the potential stability of Ag/AgCl/CNTs was still good within 60 days of immersion in solution. Its linear response slope is 49.91mV, and it has smaller charge transfer resistance and larger corrosion current density. It is a promising concrete Cl- concentration monitoring sensor.
【學(xué)位授予單位】：華中科技大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：TU375;TP212

【相似文獻(xiàn)】

相關(guān)期刊論文 前10條

1 江根林;林軍;葛雨寶;;摻雜AgCl晶體的生長與應(yīng)用[J];光學(xué)儀器;1992年01期

2 郜洪文;;雙波長分光光度法測定天然水體常量物質(zhì)——AgCl膠體生成分析Cl~-[J];儀器儀表與分析監(jiān)測;1992年01期

3 林生嶺;文丹;程小芳;劉東瑤;;AgCl/HAP納米復(fù)合材料的制備及其光催化性能[J];江蘇科技大學(xué)學(xué)報(自然科學(xué)版);2013年02期

4 衛(wèi)云鴿;曹全喜;雷夢碧;黃云霞;王毓鵬;;全固體Ag/AgCl電極的制備工藝研究[J];功能材料;2010年S3期

5 滿亞輝;吳文健;張學(xué)驁;劉長利;胡碧茹;王建方;;改進(jìn)AgCl濁度法測定艦船火災(zāi)煙氣中氯[J];國防科技大學(xué)學(xué)報;2005年06期

6 張玉濤，，王秀芝;雙碳纖維束－Ag／AgCl組合電極的制備、性質(zhì)和應(yīng)用[J];東北大學(xué)學(xué)報;1995年05期

7 李迪,李景虹;3-Mercaptopropionic Acid Capped Gold Nanoclusters: Quantized Capacitance in Aqueous Media[J];Chinese Journal of Chemistry;2003年04期

8 ;Measurement of ~(36)Cl With Gas-Filled Time-of-Flight Method[J];Annual Report for China Institute of Atomic Energy;2005年00期

9 ;感光原理、材料及參數(shù)測試[J];中國光學(xué)與應(yīng)用光學(xué)文摘;1994年06期

10 宋成芳,張慶慶,湯斌;AgCl膜光催化降解色素的研究[J];安徽工程科技學(xué)院學(xué)報(自然科學(xué)版);2003年01期

相關(guān)會議論文 前8條

1 張爽;佟洋;盛杰;孫聞東;;利用水熱法合成不同形貌的納米AgCl[A];中國化學(xué)會第26屆學(xué)術(shù)年會膠體與界面化學(xué)分會場論文集[C];2008年

2 林健;井沖;李博芳;黃文e

本文編號：2234052