(1.中南工業(yè)大學(xué)冶金物理化學(xué)與化學(xué)新材料研究所,長(zhǎng)沙 410083;
2.深圳中金實(shí)業(yè)股份有限公司, 深圳 518000)
摘 要: 采用二步法先合成鉀的石墨層間化合物,然后再通過(guò)它合成Co, Ni系石墨層間化合物。化學(xué)分析、 X射線衍射、X射線光電子能譜及透射電鏡的分析結(jié)果表明,這些化合物中金屬主要以正2價(jià)形態(tài)存在,化合物的粒度為納米級(jí)。用微電極測(cè)試了它們?cè)贙OH溶液中對(duì)氧還原的催化活性,發(fā)現(xiàn)C48Co及C48Ni為好,尤以C48Co為優(yōu);加入C48Co的氣體擴(kuò)散電極的電流密度,比未加的高68倍。用旋轉(zhuǎn)圓盤(pán)電極研究了對(duì)氧的還原過(guò)程, 發(fā)現(xiàn)該過(guò)程同時(shí)受擴(kuò)散與化學(xué)反應(yīng)兩種作用的混合控制,反應(yīng)電子數(shù)為2。
關(guān)鍵字: 鎳 鈷 石墨層間化合物
(1.Institute of Metallurgical Physicochemistry and Chemical Materials,Central South University of Technology, Changsha 410083, P. R. China;
2.Shenzhen Zhongjin Corp. Ltd, Shenzhen 518000, P. R. China)
Abstract:Graphite intercalation compounds(GICs)-Co and GICs-Ni have been successfully synthesized with the GICs-K as intermediates, and the compounds have been analyzed with chemical analysis, X-ray diffraction, X-ray photoelectron spectroscopy(XPS), transmission electron microscopy(TEM). The valences of Co and Ni in the compounds are both +2. The particle size of these compounds is in the order of nm. The experimental results of powder microelectrodes indicated that C48Co is the best one for oxygen reduction among all the GICs-Co and GICs-Ni compounds studied. The soft embeded rotating disk electrode(RDE) experiments indicated oxygen reduction on the surface of GICs-Co is jointly controlled by diffusion and electr ochemical reaction, the number of electron transfer of oxygen reduction is 2. The preparation of peroxides using gas diffusion electrodes with catalyst C48Co indicated that the cathodic current density is 68 times higher than that without C48Co, the current efficiency is 93%.
Key words: nickel cobalt graphite intercalation compound


