本文選題：Co_3O_4 + 鐵摻雜��； 參考：《北京化工大學(xué)》2015年碩士論文

【摘要】：氧氣析出反應(yīng)在燃料電池和電解水制氫等能源領(lǐng)域中具有廣泛的應(yīng)用。目前,貴金屬及貴金屬氧化物(如Ru、Ir、RuO2、IrO2等)是氧氣析出反應(yīng)常用的催化劑,然而貴金屬價格昂貴、儲量稀少,限制了其進(jìn)一步應(yīng)用。因此,研究開發(fā)低成本、高性能的氧氣析出反應(yīng)催化劑具有重要意義。本論文致力于研究低成本、高性能的非貴金屬一一四氧化三鈷(Co3O4)基氧氣析出反應(yīng)催化劑,通過形貌調(diào)控、碳載體負(fù)載以及金屬摻雜進(jìn)一步提高Co3O4的比表面積和電導(dǎo)率,從而有效提高催化劑的電催化活性和穩(wěn)定性。首先,采用水熱法制備了尖晶石結(jié)構(gòu)的Co3O4,通過調(diào)控堿濃度、反應(yīng)溫度、醇水比等條件,實現(xiàn)了對催化劑微觀形貌的有效調(diào)控,合成Co3O4納米顆粒、納米棒、納米塊、納米線、納米片等催化劑。物性表征和電化學(xué)測試表明,催化劑的微觀形貌對其電催化活性影響較大,其中粒徑為4-7 nm的Co3O4納米顆粒催化劑具有最高的催化活性,在電流密度為10 mA·cm-2條件下,電位為0.690V (vs.SCE)。其次,為提高Co3O4催化劑的比表面積和電導(dǎo)率,采用高溫石墨化炭黑(GCB)為載體,通過油浴攪拌法制備了Co3O4/GCB催化劑,通過調(diào)控?zé)崽幚頊囟取⒋妓纫约柏?fù)載量等條件,提高了Co3O4/GCB催化劑的氧氣析出催化活性。研究表明,所制備的催化劑Co3O4納米顆粒在GCB載體上分散較均勻,粒徑約為5 nnl,具有較大的比表面積和較低的電阻率。電化學(xué)測試表明,Co3O4/GCB催化劑具有優(yōu)于Co3O4催化劑的氧氣析出催化活性和電化學(xué)穩(wěn)定性,在10 mA·cm-2條件下,電位減小為0.670V,穩(wěn)定性測試中,在一定電位下,Co304催化劑和Co3O4/GCB催化劑電流密度的衰減分別為10%和20%。最后,采用鐵對Co3O4/GCB催化劑進(jìn)行摻雜,制備了FexCoyO4/GCB催化劑,和Co3O4催化劑相比電阻率減小,進(jìn)一步提高了氧氣析出催化活性。在電流密度為10 mA·cm-2條件下,FexCoyO4/GCB催化劑的電位為0.637 V,較未摻雜的Co3O4/GCB催化劑減小了33 mV,具有優(yōu)異的氧氣析出催化活性。穩(wěn)定性測試表明,經(jīng)過1000圈電化學(xué)掃描,FexCoyO4/GCB催化劑幾乎未發(fā)生衰減,表現(xiàn)出優(yōu)異的電化學(xué)穩(wěn)定性。Co3O4基催化材料因其優(yōu)異的氧氣析出反應(yīng)催化能力,在新能源技術(shù)的發(fā)展中表現(xiàn)出良好的潛力。
[Abstract]:Oxygen precipitation reaction has been widely used in fuel cell and electrolytic water for hydrogen production. At present, precious metals and precious metal oxides (such as Ruziru, Ruo _ 2o _ 2o _ 2 and so on) are common catalysts for oxygen precipitation reaction. However, precious metals are expensive and have few reserves, which limit their further application. Therefore, it is of great significance to develop low-cost and high-performance catalysts for oxygen precipitation reaction. In this paper, the low cost and high performance catalysts for oxygen precipitation of non-noble metal cobalt trioxide (Co _ 3O _ 4) were studied. The surface area and conductivity of Co3O4 were further improved by means of morphology control, carbon carrier loading and metal doping. Thus, the electrocatalytic activity and stability of the catalyst are improved effectively. Firstly, Co _ 3O _ 4 with spinel structure was prepared by hydrothermal method. By controlling the concentration of alkali, reaction temperature and ratio of alcohol to water, the Co3O4 nanoparticles, nanorods, nanomaterials and nanowires were synthesized. Nanoparticles, etc. The results of physical characterization and electrochemical test showed that the micromorphology of the catalyst had a great influence on the electrocatalytic activity, and the Co3O4 nanoparticles with a particle size of 4-7 nm had the highest catalytic activity. The potential was 0.690 V / v 路SCEN at the current density of 10 Ma / cm-2. Secondly, in order to improve the specific surface area and conductivity of Co3O4 catalyst, Co3O4/GCB catalyst was prepared by oil bath stirring method using high temperature graphitization carbon black as the carrier. The temperature of heat treatment, the ratio of alcohol to water and the loading amount were adjusted. The oxygen precipitation activity of Co3O4/GCB catalyst was improved. The results show that the prepared catalyst Co3O4 nanoparticles are uniformly dispersed on the GCB support with a particle size of about 5 nnl.The catalyst has a large specific surface area and low resistivity. Electrochemical measurements showed that the catalytic activity of CO _ 3O _ 4 / GCB catalyst was superior to that of Co3O4 catalyst in oxygen precipitation and electrochemical stability. At 10 Ma cm-2, the potential decreased to 0.670 V, and in the stability test, the oxygen precipitation activity of Co _ 3O _ 4 / GCB catalyst was better than that of Co3O4 catalyst. The decay of current density of Co304 catalyst and Co3O4/GCB catalyst is 10% and 20% respectively at certain potential. Finally, Co3O4/GCB catalyst was doped with iron to prepare FexCoyO4/GCB catalyst. Compared with Co3O4 catalyst, the resistivity of FexCoyO4/GCB catalyst was reduced, which further improved the catalytic activity of oxygen precipitation. At the current density of 10 Ma cm-2, the potential of FexCoyO4 / GCB catalyst is 0.637 V, which is 33 MV lower than that of undoped Co3O4/GCB catalyst, and has excellent catalytic activity for oxygen precipitation. The stability test showed that the catalyst of FexCoyO4 / GCB had almost no decay after 1000 cycles of electrochemical scanning, and showed excellent electrochemical stability. Co3O4-based catalyst showed excellent catalytic ability for oxygen precipitation reaction. Show good potential in the development of new energy technology.
【學(xué)位授予單位】：北京化工大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：TQ138.12;O643.36

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本文編號：1823026