本文選題：鋰-空氣電池 + 鈀負載�。� 參考：《燕山大學》2014年碩士論文

【摘要】：本文采用硬模板法和電泳技術(shù)成功制備了Pd負載的具有多級孔道結(jié)構(gòu)的碳材料(Pd-modified hollow sphere carbon，PHSC)一體化正極。并以該復合材料為研究對象，運用X射線衍射(XRD)、熱重分析(TG-DSC)、掃描電鏡(SEM)、能譜(EDS)、透射電鏡(TEM)、比表面積分析(BET)、拉曼光譜(Raman)和紅外光譜分析(IR)對復合材料進行了表征。運用恒電流充放電、交流阻抗(EIS)和循環(huán)伏安(CV)等方法對其電化學性能進行測試和分析，系統(tǒng)的研究了復合材料的形貌、結(jié)構(gòu)和電化學性能。并對放電產(chǎn)物進行了定量分析。 經(jīng)過XRD圖譜分析得出Pd顆粒結(jié)晶性良好，并成功負載在碳球殼內(nèi)，TG-DSC測試表明Pd含量為25wt.%。通過SEM可以看出碳球殼已經(jīng)牢固地沉積在碳紙的框架中。孔分布曲線得出該材料有3nm和20-100nm兩種孔道結(jié)構(gòu)，用BET法計算得出該材料的比表面為127m2/g，BJH法測得孔體積為0.22cm3/g。TEM得出Pd粒子的顆粒大小為10-15nm，碳球殼的壁厚為9.19nm。 限定放電比容量為3000mAh/g，在300mA/g電流密度下放電，與傳統(tǒng)的SP碳和無鈀負載碳球殼(HSC)電極相比，PHSC電極的過電位分別降低了300mV和490mV，大幅度提高了能量轉(zhuǎn)換效率。CV測試使該結(jié)果得到了證實。用該材料作鋰-空氣電池的正極在1.5A/g的電流密度下放電比容量可以達到5900mAh/g。限定充放電比容量為1000mAh/g，以300mA/g的電流密度充放電，電池可以循環(huán)205次。 我們對放電產(chǎn)物進行了SEM表征，，結(jié)果發(fā)現(xiàn)SP電極的放電產(chǎn)物Li2O2呈圓盤狀，而我們制備的PHSC電極的放電產(chǎn)物Li2O2為片狀結(jié)構(gòu)，厚度為10nm左右，均勻生長在碳球殼表面。對放電過程中的放電產(chǎn)物予以定量分析，PHSC電極在100次循環(huán)之后Li2O2的含量達到81.6%。 以Pd負載的多孔碳一體化電極為空氣電極，該鋰-空氣電池性能得到了大幅度提高，這些優(yōu)異的性能歸因于Pd納米粒子的催化活性與空氣電極的孔道結(jié)構(gòu)，設計結(jié)構(gòu)更加合理的空氣電極將是鋰-空氣電池未來發(fā)展的一個新方向。
[Abstract]:In this paper, the Pd-modified hollow sphere carbon (PHSC) cathode supported by PD was successfully prepared by hard template method and electrophoretic technique. The composites were characterized by X-ray diffraction (XRD), thermogravimetric analysis (TG-DSC), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), transmission electron microscopy (TEM), specific surface area analysis (BET), Raman spectroscopy (Raman) and infrared spectroscopy (IR). The electrochemical properties of the composites were measured and analyzed by means of constant current charge-discharge, alternating current impedance (EIS) and cyclic voltammetry (CV). The morphology, structure and electrochemical properties of the composites were systematically studied. The discharge products were quantitatively analyzed. XRD analysis showed that the crystallinity of PD particles was good, and the TG-DSC results showed that the PD content was 25 wt.TG-DSC. It can be seen by SEM that the carbon spherical shell has been firmly deposited in the framework of carbon paper. The pore distribution curves show that the material has two kinds of pore structures: 3nm and 20-100nm. The specific surface area of the material is 127m2 / g / g BJH method. The pore volume measured by BJH method is 0.22 cm ~ 3 / g 路TEM. The particle size of PD particles is 10-15 nm and the wall thickness of carbon spherical shell is 9.19 nm. The specific discharge capacity is 3,000 mAh-g, which is discharged at the current density of 300mA/g. Compared with the conventional SP carbon and palladium free carbon spherical shell (HSC) electrodes, the overpotential of PHSC electrode is reduced by 300mV and 490mV, respectively. Using this material as the cathode of lithium-air battery, the discharge specific capacity can reach 5900mAh / g at the current density of 1.5A/g. The limited charge-discharge capacity is 1000mAh / g, and the battery can be recirculated 205 times at the current density of 300mA/g. The discharge products were characterized by SEM. It was found that the discharge product Li _ 2O _ 2 of SP electrode was disk-shaped, while that of discharge product Li _ 2O _ 2 of our prepared electrode was flake structure with thickness of about 10nm, and it grew uniformly on the surface of carbon spherical shell. Quantitative analysis of discharge products during discharge the content of Li _ 2O _ 2 in PHSC electrode reached 81.6 after 100 cycles. The performance of the lithium-air battery was greatly improved by using the porous carbon electrode supported by PD as the air electrode. These excellent properties were attributed to the catalytic activity of PD nanoparticles and the pore structure of the air electrode. The design of air electrode with more reasonable structure will be a new direction in the future development of lithium-air battery.
【學位授予單位】：燕山大學
【學位級別】：碩士
【學位授予年份】：2014
【分類號】：TM911.41;O646.5

【參考文獻】

相關(guān)期刊論文 前7條

1 劉春娜;;鋰/空氣電池研究最新進展[J];電源技術(shù);2011年06期

2 郭麗敏;彭章泉;;非水溶劑鋰-空氣電池中的氧氣電極反應[J];分析化學;2013年02期

3 黃征;池波;蒲健;李箭;;高性能鋰-空氣電池材料的研究[J];化學進展;2013年Z1期

4 程方益;陳軍;;可充鋰空氣電池多孔納米催化劑[J];化學學報;2013年04期

5 顧大明;王余;顧碩;張傳明;楊丹丹;;鋰空氣電池非水基電解液的優(yōu)化與研究進展[J];化學學報;2013年10期

6 李加新;趙毅;吳初新;賴恒;黃志高;官輪輝;;有機系鋰-空氣電池碳基正極的研究進展[J];科學通報;2013年31期

7 郭向欣;黃詩婷;趙寧;崔忠慧;范武剛;李馳麟;李泓;;二次鋰空氣電池研究的快速發(fā)展及其急需解決的關(guān)鍵科學問題[J];無機材料學報;2014年02期

本文編號：2074192