本文選題：乙醇氧化反應(yīng)　切入點(diǎn)：石墨烯　出處：《河北師范大學(xué)》2017年碩士論文　論文類型：學(xué)位論文

【摘要】：直接乙醇燃料電池(DEFCs)已經(jīng)被公認(rèn)為是非常有前途的能量轉(zhuǎn)換器。它可以直接把乙醇中儲存的化學(xué)能轉(zhuǎn)換成電能。在本論文中,除了用水熱法制備Pd基催化劑之外,還采用了以水熱法為基礎(chǔ),在電沉積過程中通過循環(huán)伏安法、計(jì)時(shí)電流法制備石墨烯負(fù)載的Pd基催化劑。利用SEM和TEM表征方法觀察催化劑的結(jié)構(gòu)和形貌。利用循環(huán)伏安法、計(jì)時(shí)電流法和阻抗法等一系列電化學(xué)測試方法探究催化劑對乙醇的電催化活性。主要實(shí)驗(yàn)內(nèi)容如下:1.首先,我們將PdO和石墨烯在一定條件下熱解,制得的樣品固定在玻碳(GC)電極上,然后就可以得到經(jīng)過熱解處理的PdO/G負(fù)載的玻碳電極。我們采用了循環(huán)伏安掃描的方法,在一定的電勢范圍內(nèi),更換了四種不同的掃速對上述制得的樣品進(jìn)行掃描,循環(huán)圈數(shù)均為50圈,這樣就得到了四種不同掃速處理的PdO/石墨烯負(fù)載的GC電極,在這項(xiàng)工作中,掃速分別為5、10、50和90mV s-1,上述制得的催化劑記為a、b、c和d。樣品的形貌特征主要通過掃描電子顯微鏡(SEM)和透射電子顯微鏡(TEM)表征。所制備的催化劑對乙醇氧化反應(yīng)(EOR)的電催化活性主要通過循環(huán)伏安法(CV)和計(jì)時(shí)電流法進(jìn)行測試。電化學(xué)測試結(jié)果表明,掃速為10mV s-1制得的PdO/G催化劑的電催化性能最好。該催化劑優(yōu)于其他催化劑的主要原因是它的Pd含量相對較多并且粒徑相對較小。2.將PdO和石墨烯組成的懸浮溶液放入馬弗爐中,在200℃下煮沸2小時(shí),過濾并干燥,將最后所得樣品表示為PdO/G材料。然后,將樣品固定在玻碳(GC)電極上,產(chǎn)生PdO/G涂覆的GC電極。最后,在含有PdCl_2和Na2SO4的溶液中,以10mV s-1的掃描速率,通過恒電位的方法掃描制備各種循環(huán)圈數(shù)(0,20,50和80個(gè)循環(huán))的電極,這樣就產(chǎn)生四種PdO/G電極(記為催化劑a、b、c和d),表示為電位掃描周期(PSC)處理的PdO/G電極。樣品的形貌主要通過掃描電子顯微鏡(SEM)和透射電子顯微鏡(TEM)表征。PSC處理的催化劑對乙醇氧化反應(yīng)(EOR)的電催化能力主要通過循環(huán)伏安法(CV)和計(jì)時(shí)電流法(CA)檢測。電化學(xué)結(jié)果表明,通過50個(gè)循環(huán)處理的PdO/G催化劑(催化劑c)在所有制備的催化劑中表現(xiàn)出了最好的電催化活性。與其它催化劑相比,較小的粒徑和較高的金屬Pd含量被認(rèn)為是催化劑c對EOR優(yōu)異的電催化活性的主要原因。實(shí)驗(yàn)結(jié)果表明,掃描周期是一種可以提高PdO/G復(fù)合材料對EOR電催化活性的方法。3.通過熱解法制備PdO和石墨烯復(fù)合材料,然后將得到的復(fù)合材料涂覆在玻碳電極上,在含有PdCl_2和Na2SO4的溶液中,通過計(jì)時(shí)電流法,施加不同的負(fù)電位(-0.65V,-0.75V和-0.85V)制備出三種PdO/G電極,分別記為催化劑a、催化劑b和催化劑c。催化劑的結(jié)構(gòu)和形貌主要通過掃描電子顯微鏡(SEM)和透射電子顯微鏡(TEM)表征。催化劑對乙醇的電催化活性主要通過循環(huán)伏安法、計(jì)時(shí)電流法和阻抗法檢測。電化學(xué)測試結(jié)果表明,催化劑b對EOR的催化效果更好。因?yàn)榇呋瘎゜的顆粒粒徑最小,并且與其他催化劑相比,催化劑b中金屬Pd的含量最多,所以我們認(rèn)為催化劑b對乙醇的電催化效果最好。4.將PdO與PdCl_2按摩爾比為1:1放入玻璃瓶中,然后把石墨烯放入到玻璃瓶中,超聲30min,制得PdO、PdCl_2和石墨烯組成的懸濁液,將懸濁液放入馬弗爐中,在200℃分別煅燒3h、4h和5h,從而制得石墨烯負(fù)載的Pd基催化劑(記為催化劑a、催化劑b和催化劑c)。用SEM和TEM觀察催化劑的結(jié)構(gòu)和形貌,用循環(huán)伏安法、計(jì)時(shí)電流法和阻抗法等一系列電化學(xué)方法探究催化劑的電氧化性。從EDS圖中分析可得,催化劑b中金屬Pd的含量最高,結(jié)合SEM、TEM圖譜分析可得,催化劑b的顆粒粒徑最小。并且電化學(xué)測試結(jié)果表明,催化劑b對EOR的催化效果更好。因此我們認(rèn)為,催化劑b對乙醇的電催化活性最好。
[Abstract]:Direct ethanol fuel cell (DEFCs) has been recognized as a very promising energy converter. It can be directly stored in the ethanol chemical energy into electrical energy. In this paper, in addition to hydrothermal preparation of Pd catalysts, also by hydrothermal method as the foundation, by cyclic voltammetry the electrodeposition process, the preparation of Pd based catalysts supported on graphene chronoamperometry method. To observe the structure and morphology of the catalyst using SEM and TEM characterization methods. Using cyclic voltammetry, chronoamperometry and electrochemical impedance method and a series of test methods on electrocatalytic activity for ethanol catalytic agent. The main contents are as follows: 1. first experiment we will, PdO and graphene pyrolysis under certain conditions, the prepared samples immobilized on glassy carbon electrode (GC), then you can get through the glassy carbon electrode pyrolysis PdO/G load. We use cyclic voltammetry Scanning method in a certain range of potential, the replacement of the four different scan rate scan of the prepared samples, the number of cycles was 50 laps, so that you get the GC electrode four different scan rate processing PdO/ graphene load, in this work, the sweep speed respectively. 5,10,50 and 90mV s-1, the prepared catalyst is denoted as a, B, C and D. morphology of the sample by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) characterization. The prepared catalysts for ethanol oxidation (EOR) electrocatalytic activity mainly by cyclic voltammetry (CV) and chronoamperometry test. The electrochemical test results show that the sweep speed for the electrocatalytic performance of PdO/G catalyst 10mV S-1 was the best. The main reason for the catalyst is better than that of other catalysts is Pd the content of the relatively large particle size is relatively small and.2. PdO and graphene. The suspension solution into the muffle furnace, under the temperature of 200 DEG C to boil for 2 hours, filtering and drying, the final sample expressed as PdO/G material. Then, the sample was immobilized on glassy carbon electrode (GC), GC PdO/G coated electrode. Finally, the solution containing PdCl_2 and Na2SO4, with the scan rate 10mV s-1, by scanning the potentiostatic method to prepare a variety of number of cycles (0,20,50 and 80 cycles) of the electrode, resulting in four kinds of PdO/G electrode (denoted as B, catalyst a, C and D), expressed as a potential scanning cycle (PSC) PdO/G electrode treatment. The morphologies of the samples by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) characterization of.PSC catalysts for ethanol oxidation treatment (EOR) electrocatalytic ability mainly by cyclic voltammetry (CV) and chronoamperometry (CA) detection. The electrochemical results show that through 50 cycles of treatment of the PdO/G catalyst (C catalyst ) in all the catalysts prepared showed the best electrocatalytic activity. Compared with other catalysts, smaller particle size and higher content of metal Pd is thought to be a catalyst for C EOR with excellent electrocatalytic activity for the main reason. The experimental results show that the scanning cycle is a method to improve the electrocatalytic EOR the activity of the PdO/G composite material.3. and preparation of PdO graphene composite materials by pyrolysis method, and the obtained composite material coated on glassy carbon electrode, in aqueous solution containing PdCl_2 and Na2SO4, chronoamperometry by applying a negative potential different (-0.65V, -0.75V and -0.85V) were prepared by three kinds of PdO/G electrode. They were recorded as a catalyst, the structure and morphology of catalyst B and C. catalysts by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) characterization of the catalyst. The electrocatalytic activity for ethanol mainly by cyclic volt ANN method, chronoamperometry and impedance detection method. The electrochemical test results show that the better catalytic effect of catalyst B on EOR. Because the particles of B catalyst particle size, and compared with other catalysts, the most content of metal Pd B catalyst, so we think that the electrocatalytic effect of B catalyst for ethanol best.4. PdO with the PdCl_2 molar ratio of 1:1 in a glass bottle, then put the graphene into glass bottles, ultrasonic 30min, preparation of PdO, PdCl_2 and graphene is composed of suspension, the suspension is placed in a muffle furnace, at a temperature of 200 DEG C respectively 4H and 5h, 3h burning, so as to prepare Pd based catalysts supported on graphene (remember catalyst a, catalyst B and C catalyst). Structure and morphology of SEM and TEM on the catalyst, using cyclic voltammetry, chronoamperometry and electrochemical impedance method and a series of methods to explore the electro oxidation of catalyst. From the EDS diagram analysis The content of metal Pd in catalyst B is the highest. Combined with SEM and TEM analysis, the particle size of catalyst B is the smallest. The electrochemical test results show that the catalyst B has better catalytic effect on EOR. Therefore, we believe that the catalyst B has the best electrocatalytic activity for ethanol.

【學(xué)位授予單位】：河北師范大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2017
【分類號】：O643.36;TM911.4

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2 ;催化劑研究的成就[J];科學(xué)通報(bào);1959年22期

3 董德昌;硫酸用的釩催化劑形狀的工業(yè)概念[J];化學(xué)世界;1986年11期

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