基于聚離子液體的酚類電催化研究
發(fā)布時(shí)間：2019-06-14 21:25
【摘要】：酚類化合物一直作為一類毒性強(qiáng)、來(lái)源廣且難降解的有機(jī)污染物躋身水中優(yōu)先控制污染物的黑名單,對(duì)人類身體健康與生存環(huán)境構(gòu)成嚴(yán)重威脅。從分子結(jié)構(gòu)理論可知,酚類化合物包含的苯環(huán)兀電子離域效應(yīng),使這類化合物的結(jié)構(gòu)變得緊湊而牢固,化學(xué)性質(zhì)穩(wěn)定,難以降解。近年來(lái),電化學(xué)處理法憑借低能耗,高效率,少污染等特點(diǎn)成為含酚污水處理領(lǐng)域的研究熱點(diǎn),而離子液體型導(dǎo)電聚合物也以其優(yōu)良的電化學(xué)性能成為電催化酚類污染物常用的電極修飾材料。本論文采用電化學(xué)聚合方法,制備了聚離子液體(poly[ABMI]PF_6)和聚離子液體-納米二氧化鈦復(fù)合物(poly[ABMI]PF_6-TiO_2)兩種電催化材料。采用電化學(xué)測(cè)試方法分別研究了苯酚在聚離子液體膜修飾金電極(poly[ABMI]PF_6/Au)和對(duì)苯二酚(HQ)、鄰苯二酚(CC)在聚離子液體-納米二氧化鈦復(fù)合物膜修飾金電極(poly[ABMI]PF_6-TiO_2/Au)上的電化學(xué)行為。具體研究?jī)?nèi)容如下：(1)結(jié)合苯胺的可聚性與離子液體的可設(shè)計(jì)性,以咪唑、間硝基氯芐、1,4-二溴丁烷等為原料通過(guò)兩步法合成功能化可聚雙咪唑型離子液體(ABMI),紅外光譜(IR),核磁共振(NMR) H譜和C譜等表征結(jié)果表明合成產(chǎn)物與目標(biāo)化學(xué)物結(jié)構(gòu)一致。采用計(jì)時(shí)電流法在Au電極上電聚合得到poly[ABMI]PF_6膜,結(jié)合離子液體聚合的2D和3D無(wú)因次理論模型推導(dǎo)出了離子液體在Au電極上的電化學(xué)聚合過(guò)程為擴(kuò)散控制下的三維瞬時(shí)成核。在分散有納米Ti02的電解液中,采用計(jì)時(shí)電流法在Au電極上電聚合得到poly[ABMI]PF_6-TiO_2復(fù)合膜,結(jié)合ABMI聚合的2D和3D無(wú)因次理論模型推導(dǎo)出了ABMI-TiO_2在Au電極上的電化學(xué)聚合過(guò)程同樣遵循擴(kuò)散控制下的三維瞬時(shí)成核理論。對(duì)比ABMI和ABMI-TiO_2循環(huán)伏安聚合過(guò)程進(jìn)一步說(shuō)明ABMI在Au電極上電化學(xué)聚合原理與ABMI-TiO_2在Au電極上的基本一致。通過(guò)掃描電鏡(SEM)表征實(shí)現(xiàn)對(duì)poly[ABMI]PF_6和poly[ABMI]PF_6-TiO_2膜結(jié)構(gòu)與形貌的分析。(2)應(yīng)用循環(huán)伏安法技術(shù)(CV)和交流阻抗技術(shù)(EIS)對(duì)poly[ABMI]PF_6/Au電極的電化學(xué)性能進(jìn)行了測(cè)試,結(jié)果表明poly[ABMI]PF_6/Au電極具有良好的電子傳遞能力。采用循環(huán)伏安法分別研究了poly[ABMI]PF_6/Au電極和Au電極對(duì)苯酚的電催化行為,發(fā)現(xiàn)相對(duì)于Au電極,poly[ABMI]PF_6/Au電極對(duì)苯酚電催化有良好的增強(qiáng)效果,且電極反應(yīng)為1電子1質(zhì)子參與的不可逆氧化反應(yīng)。同時(shí)考察了緩沖液種類、pH、富集時(shí)間、掃描速率和電解液溫度對(duì)苯酚的電催化氧化效果的影響,并對(duì)相關(guān)電化學(xué)參數(shù)進(jìn)行了測(cè)試。苯酚氧化峰電流值與掃描速率的關(guān)系表明當(dāng)掃描速率(v)在0.02～0.1 V/s范圍時(shí),苯酚在poly[ABMI]PF_6/Au電極上的電化學(xué)氧化過(guò)程是由擴(kuò)散過(guò)程控制,當(dāng)v在0.2～0.9 V/s范圍內(nèi)時(shí),苯酚的氧化反應(yīng)轉(zhuǎn)由吸附過(guò)程控制；苯酚氧化峰電流值與溫度(25～45℃)的關(guān)系式表明在poly[ABMI]PF_6/Au電極上,苯酚的電催化氧化反應(yīng)活化能△G為30.74 kJ'mol~(-1);一定濃度范圍內(nèi)苯酚的氧化峰電流值與濃度之間呈良好的線性關(guān)系,表明此聚離子液體膜修飾電極能夠高靈敏度檢測(cè)苯酚,并有望用來(lái)對(duì)水體中的苯酚進(jìn)行電化學(xué)催化氧化處理。對(duì)于拓展聚離子液體的功能及性質(zhì),構(gòu)建苯酚電化學(xué)催化氧化新方法和新器件具有重要意義。(3)應(yīng)用CV和EIS對(duì)poly[ABMI]PF_6-TiO_2膜的電化學(xué)性能進(jìn)行了測(cè)試,結(jié)果表明poly[ABMI]PF_6-TiO_2/Au電極具有良好的電子傳遞能力。采用循環(huán)伏安法和差分脈沖伏安法分別研究了poly[ABMI]PF_6-TiO_2/Au電極、Au電極、poly[ABMI]PF_6/Au電極和TiO_2/Au電極對(duì)HQ和CC的電催化行為,發(fā)現(xiàn)相對(duì)于其他幾種電極,poly[ABMI]PF_6-TiO_2/Au電極對(duì)HQ和CC的電催化氧化還原均有良好的增強(qiáng)效果。同時(shí)考察了緩沖液種類、pH、掃描速率和電解液溫度對(duì)HQ和CC電催化性能的影響,并對(duì)相關(guān)電化學(xué)參數(shù)進(jìn)行了測(cè)試。HQ和CC氧化峰電流值,還原峰電流值分別與掃描速率的關(guān)系表明HQ和CC在poly[ABMI]PF_6-TiO_2/Au電極上的電催化反應(yīng)均是由擴(kuò)散過(guò)程控制的2電子2質(zhì)子參與的可逆電化學(xué)氧化還原過(guò)程,且修飾電極的有效面積A為0.1073 cm~2,HQ和CC擴(kuò)散系數(shù)D分別為3.591×10-7 cm~2/s和1.913×10-6 cm~2/s;HQ和CC擴(kuò)散系數(shù)與溫度(25～45℃)的關(guān)系式表明在poly[ABMI]PF_6-TiO_2/Au電極上,HQ和CC反應(yīng)活化能△G分別為49.39 kJ·mol~(-1)和34.93 kJ·mol~(-1);一定濃度范圍內(nèi)HQ和CC的差分脈沖伏安測(cè)試表明poly[ABMI]PF_6-TiO_2/Au電極能夠高靈敏度的同時(shí)和選擇性檢測(cè)HQ和CC,并有望用來(lái)對(duì)水體中的HQ和CC進(jìn)行電化學(xué)區(qū)分和電催化氧化還原處理。
[Abstract]:The phenolic compounds have been listed as a class of organic pollutants with strong toxicity, wide source and difficult to degrade, and the black list of the pollutants is preferentially controlled in the water, which poses a serious threat to the human health and the living environment. It is known from the molecular structure theory that the benzene ring of the phenolic compound has the electron-leaving effect, so that the structure of the compound becomes compact and firm, the chemical property is stable, and the compound is difficult to degrade. In recent years, the electrochemical treatment method has become a hot spot in the field of phenol-containing sewage treatment with low energy consumption, high efficiency and less pollution. In this paper, two kinds of electrocatalytic materials of polyionic liquid (poly[ABMI] PF _ 6) and poly ([ABMI] PF _ 6-TiO _ 2) were prepared by electrochemical polymerization. The electrochemical behavior of phenol in poly (ionic liquid membrane modified gold electrode (poly[ABMI] PF _ 6/ Au) and hydroquinone (HQ) and catechol (CC) on the modified gold electrode (poly[ABMI] PF _ 6-TiO _ 2/ Au) was studied by electrochemical test method. The specific contents of the study are as follows: (1) The properties of the polycidetomidine-type ionic liquid (ABMI) and the infrared spectrum (IR) are synthesized by a two-step method, such as detomidine, m-nitrochlorobenzene, 1,4-dibromobutane, and the like in combination with the designability of the ionic liquid of the aniline. The results of nuclear magnetic resonance (NMR) H-spectrum and C-spectrum show that the synthesis product is consistent with the target chemical structure. A poly[ABMI] PF _ 6 film was obtained by the time-current method on the Au electrode, and the three-dimensional transient nucleation of the ionic liquid under the diffusion control was derived by the 2D and 3D dimensionless theoretical models of the ionic liquid polymerization. In the electrolyte with nano Ti02, a poly[ABMI] PF _ 6-TiO _ 2 composite film was obtained by the time-current method on the Au electrode, and the two-dimensional and 3D non-dimensional theoretical model of ABMI polymerization was used to derive the three-dimensional transient nucleation theory under the diffusion control. Compared with ABMI and ABMI-TiO _ 2 cyclic voltammetry, the electrochemical polymerization principle of ABMI on Au electrode and ABMI-TiO _ 2 are consistent with that of ABMI-TiO _ 2 on Au electrode. The structure and morphology of poly[ABMI] PF _ 6 and poly[ABMI] PF _ 6-TiO _ 2 were characterized by scanning electron microscopy (SEM). (2) The electrochemical performance of poly[ABMI] PF _ 6/ Au electrode was tested by cyclic voltammetry (CV) and AC impedance (EIS). The results show that the poly[ABMI] PF _ 6/ Au electrode has good electron transfer ability. The electrocatalytic behavior of poly[ABMI] PF _ 6/ Au electrode and Au electrode on phenol was studied by cyclic voltammetry. It was found that the poly[ABMI] PF _ 6/ Au electrode had a good effect on the electrocatalysis of phenol with respect to the Au electrode, and the electrode reaction was the irreversible oxidation reaction of 1 electron 1 proton. The effect of buffer type, pH, concentration time, scanning rate and electrolyte temperature on the electrocatalytic oxidation of phenol was also investigated, and the related electrochemical parameters were tested. The relationship between the peak current value and the scanning rate of the phenol shows that when the scanning rate (v) is in the range of 0.02-0.1 V/ s, the electrochemical oxidation process of the phenol on the poly[ABMI] PF _ 6/ Au electrode is controlled by the diffusion process, and when the v is within the range of 0.2-0.9 V/ s, the oxidation reaction of the phenol is controlled by the adsorption process; The relationship between the current value of phenol oxidation peak and the temperature (25 ~ 45 鈩，
本文編號(hào)：2499708
[Abstract]:The phenolic compounds have been listed as a class of organic pollutants with strong toxicity, wide source and difficult to degrade, and the black list of the pollutants is preferentially controlled in the water, which poses a serious threat to the human health and the living environment. It is known from the molecular structure theory that the benzene ring of the phenolic compound has the electron-leaving effect, so that the structure of the compound becomes compact and firm, the chemical property is stable, and the compound is difficult to degrade. In recent years, the electrochemical treatment method has become a hot spot in the field of phenol-containing sewage treatment with low energy consumption, high efficiency and less pollution. In this paper, two kinds of electrocatalytic materials of polyionic liquid (poly[ABMI] PF _ 6) and poly ([ABMI] PF _ 6-TiO _ 2) were prepared by electrochemical polymerization. The electrochemical behavior of phenol in poly (ionic liquid membrane modified gold electrode (poly[ABMI] PF _ 6/ Au) and hydroquinone (HQ) and catechol (CC) on the modified gold electrode (poly[ABMI] PF _ 6-TiO _ 2/ Au) was studied by electrochemical test method. The specific contents of the study are as follows: (1) The properties of the polycidetomidine-type ionic liquid (ABMI) and the infrared spectrum (IR) are synthesized by a two-step method, such as detomidine, m-nitrochlorobenzene, 1,4-dibromobutane, and the like in combination with the designability of the ionic liquid of the aniline. The results of nuclear magnetic resonance (NMR) H-spectrum and C-spectrum show that the synthesis product is consistent with the target chemical structure. A poly[ABMI] PF _ 6 film was obtained by the time-current method on the Au electrode, and the three-dimensional transient nucleation of the ionic liquid under the diffusion control was derived by the 2D and 3D dimensionless theoretical models of the ionic liquid polymerization. In the electrolyte with nano Ti02, a poly[ABMI] PF _ 6-TiO _ 2 composite film was obtained by the time-current method on the Au electrode, and the two-dimensional and 3D non-dimensional theoretical model of ABMI polymerization was used to derive the three-dimensional transient nucleation theory under the diffusion control. Compared with ABMI and ABMI-TiO _ 2 cyclic voltammetry, the electrochemical polymerization principle of ABMI on Au electrode and ABMI-TiO _ 2 are consistent with that of ABMI-TiO _ 2 on Au electrode. The structure and morphology of poly[ABMI] PF _ 6 and poly[ABMI] PF _ 6-TiO _ 2 were characterized by scanning electron microscopy (SEM). (2) The electrochemical performance of poly[ABMI] PF _ 6/ Au electrode was tested by cyclic voltammetry (CV) and AC impedance (EIS). The results show that the poly[ABMI] PF _ 6/ Au electrode has good electron transfer ability. The electrocatalytic behavior of poly[ABMI] PF _ 6/ Au electrode and Au electrode on phenol was studied by cyclic voltammetry. It was found that the poly[ABMI] PF _ 6/ Au electrode had a good effect on the electrocatalysis of phenol with respect to the Au electrode, and the electrode reaction was the irreversible oxidation reaction of 1 electron 1 proton. The effect of buffer type, pH, concentration time, scanning rate and electrolyte temperature on the electrocatalytic oxidation of phenol was also investigated, and the related electrochemical parameters were tested. The relationship between the peak current value and the scanning rate of the phenol shows that when the scanning rate (v) is in the range of 0.02-0.1 V/ s, the electrochemical oxidation process of the phenol on the poly[ABMI] PF _ 6/ Au electrode is controlled by the diffusion process, and when the v is within the range of 0.2-0.9 V/ s, the oxidation reaction of the phenol is controlled by the adsorption process; The relationship between the current value of phenol oxidation peak and the temperature (25 ~ 45 鈩，
本文編號(hào)：2499708
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