發(fā)布時(shí)間：2018-03-18 17:00

  本文選題：鈷酸鋅　切入點(diǎn)：尖晶石　出處：《南昌航空大學(xué)》2017年碩士論文　論文類型：學(xué)位論文

【摘要】：尖晶石結(jié)構(gòu)金屬氧化物以低廉的價(jià)格、優(yōu)秀的導(dǎo)電性能和活潑的電化學(xué)性能成為能源領(lǐng)域研究的熱點(diǎn)。本文主要研究了尖晶石結(jié)構(gòu)鋅鈷氧體系氧化物的電容和氧催化還原性能。通過尿素水熱合成的方法成功制備出鈷酸鋅,利用X射線衍射技術(shù)確定其尖晶石結(jié)構(gòu),場發(fā)射掃描電鏡觀測發(fā)現(xiàn)其粒徑約在100~300nm范圍內(nèi)。通過電化學(xué)測試,發(fā)現(xiàn)制備的電極在1、2、5和10A g~(-1)的電流密度下,電容分別為705.4、647.0、561.2和550.0F g~(-1),循環(huán)3000次后電容值下降到80.6%。通過線性掃描技術(shù)計(jì)算發(fā)現(xiàn)鈷酸鋅電極為二電子催化過程,放電20000s后,電流密度降為起始電流密度的70.5%。為了觀察鎳取代鋅對(duì)鈷酸鋅性能的影響,在制備過程中控制鋅和鎳的比例,分別制備出Zn_(1-x)Ni_xCo_2O_4(x=0、0.2、0.4、0.6、0.8和1)粉體,實(shí)驗(yàn)結(jié)果表明:摻雜鎳后的材料仍然為尖晶石結(jié)構(gòu),但是表面形貌都發(fā)生了細(xì)微變化。隨著鎳含量的增加,在1 A g~(-1)的電流密度下,比電容由705.4 F g~(-1)(x=0)下降到685.8 F g~(-1)(x=0.2),隨后又上升到1165.0 F g~(-1)(x=1),電極穩(wěn)定性逐漸減小。各電極都表現(xiàn)出對(duì)氧催化還原的活性。采用NiCo_2O_4為催化材料時(shí),氧氣直接通過四電子反應(yīng)步驟還原,而其他材料表現(xiàn)出二電子與四電子混合步驟。采用相似的方法研究摻雜錳對(duì)鈷酸鋅性能的影響,制備出Zn1-xMnxCo_2O_4(x=0、0.2、0.4、0.6、0.8和1)粉體,實(shí)驗(yàn)結(jié)果表明:摻雜錳后的材料仍然為尖晶石結(jié)構(gòu),表面形貌也發(fā)生了變化,隨著錳原子分?jǐn)?shù)的增大,電容性能呈現(xiàn)先增大后減小的趨勢,電極穩(wěn)定性逐漸降低。在氧催化還原方面,Zn1-xMnxCo_2O_4各電極都表現(xiàn)出明顯的催化活性,摻雜后的材料電極同時(shí)具有二電子和四電子反應(yīng)步驟。
[Abstract]:Spinel structure metal oxides at low prices, Excellent electrical conductivity and active electrochemical performance have become a hot topic in the field of energy. In this paper, the capacitance and oxygen catalytic reduction properties of spinel zinc-cobalt oxide system have been studied. Zinc Cobalt was successfully prepared by the method. The spinel structure was determined by X-ray diffraction technique. The particle size of the spinel was found to be in the range of about 100 ~ 300nm by field emission scanning electron microscopy. The electrochemical measurements showed that the prepared electrode was at the current density of 1 ~ 2G ~ (5) and 10 A ~ (-1). The capacitance of the electrode was 705.4U 647.0N 561.2 and 550.0F g ~ (-1), respectively, and the capacitance value decreased to 80.6 after 3000 cycles. It was found by linear scanning technique that the electrode was a two-electron catalytic process, and that it was 20 000 s after discharge. In order to observe the effect of zinc substituted by nickel on the properties of zinc cobalate, the ratio of zinc and nickel was controlled during the preparation process, and the ZnH1-xNixCo2O00.20.40.4n0.60.8-0.60.and 1) powders were prepared, respectively, in order to observe the effect of the current density drop to the initial current density of 70.5% of the initial current density, and to control the ratio of zinc and nickel during the preparation process, respectively. The experimental results show that the nickel doped material is still spinel structure, but the surface morphology changes slightly. With the increase of nickel content, at the current density of 1 A g ~ (-1), The specific capacitance decreased from 705.4 F / g ~ (-1) to 685.8 F / g ~ (-1) ~ 0.2g ~ (-1), and then increased to 1165.0 F / g ~ (-1) G ~ (-1) ~ (1) ~ (1) ~ (1) ~ (1) ~ (1) ~ (1) ~ (1) ~ 1 ~ (-1) F ~ (-1) F ~ (-1) G ~ (-1), and the stability of the electrode decreased gradually. All the electrodes showed the activity of catalytic reduction of oxygen. When NiCo_2O_4 was used as the catalytic material, oxygen was reduced directly by four-electron reaction. The other materials showed two-electron and four-electron mixing steps. The effect of doped manganese on the properties of zinc cobalt was studied in a similar way. Zn1-xMnxCo2O4xCo2O4xCO2O0. 2 and 1) powders were prepared. The experimental results show that the doped manganese is still spinel structure. The surface morphology also changed. With the increase of mn atom fraction, the capacitance performance increased first and then decreased, and the electrode stability gradually decreased. In the oxygen catalytic reduction, the electrode showed obvious catalytic activity at all electrodes, such as Zn1-xMnxCo2O4, Zn1-xMnxCo2O4. The doped electrode has both two electron and four electron reaction steps.
【學(xué)位授予單位】：南昌航空大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：TQ132.41;TM53

【參考文獻(xiàn)】

相關(guān)期刊論文 前1條

1 Thang Ngoc Cong;;Progress in electrical energy storage system:A critical review[J];Progress in Natural Science;2009年03期

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本文編號(hào)：1630479