本文選題：燃料電池　切入點(diǎn)：氧還原反應(yīng)　出處：《遼寧大學(xué)》2017年碩士論文

【摘要】：發(fā)展燃料電池(full cells)代替?zhèn)鹘y(tǒng)的電化學(xué)電池,是當(dāng)今社會(huì)科技發(fā)展的趨勢(shì)。燃料電池之所以沒(méi)有被大規(guī)模生產(chǎn)使用,主要是由于燃料電池本身陰極反應(yīng)的動(dòng)力學(xué)惰性,燃料電池陰極主要發(fā)生氧還原反應(yīng)(oxygen reduction reaction),這其中涉及到氣體擴(kuò)散、吸附、電子轉(zhuǎn)移、產(chǎn)物擴(kuò)散等等,是一個(gè)復(fù)雜的過(guò)程。所以,提高燃料電池陰極氧還原反應(yīng)的速率,使用高效的電催化劑是至關(guān)重要的。科研人員們?cè)诓粩嘌芯刻剿鬟^(guò)程中發(fā)現(xiàn):基于Pt的催化劑在目前是對(duì)氧還原反應(yīng)效果最好的電催化劑。然而,Pt基的電催化劑受穩(wěn)定性限制、燃料交叉的影響、CO中毒等影響,而且Pt本身屬于貴金屬,在地殼中含量低,成本高,不利于大規(guī)模商業(yè)化生產(chǎn)。因此,尋找更廉價(jià)的電催化劑來(lái)代替Pt顯得尤為重要,也是當(dāng)前的科研熱點(diǎn)之一。金屬有機(jī)骨架材料有著以下特點(diǎn),如:金屬與配體的可選擇性、比表面積大、孔隙率高且孔徑可調(diào)控、含碳量高等。本文利用金屬有機(jī)骨架作為前驅(qū)體,合成了兩個(gè)系列氮摻雜多孔碳材料作為氧還原反應(yīng)電催化劑,氮摻雜無(wú)金屬多孔碳材料NPC-800、NPC-900、NPC-1000以及Co納米粒子負(fù)載氮摻雜多孔碳材料Co@NPC-800、Co@NPC-900、Co@NPC-1000。并對(duì)這兩個(gè)系列的多孔碳材料進(jìn)行電化學(xué)性質(zhì)的研究。結(jié)果表明,兩種不同類(lèi)型的碳材料均有氧還原活性。在氮摻雜無(wú)金屬多孔碳材料中NPC-900不僅N含量較高,石墨化程度高而且電催化活性最好,其起始電位、電流密度、轉(zhuǎn)移電子數(shù)在三個(gè)樣品中是最理想的。金屬Co納米粒子負(fù)載的氮摻雜多孔碳材料,也具有非常優(yōu)越的氧還原活性,Co@NPC-800、Co@NPC-900表現(xiàn)出較好的電催化活性。利用金屬有機(jī)骨架為前驅(qū)體或模板合成多孔碳材料,并對(duì)該碳材料進(jìn)行處理,進(jìn)而得到不同類(lèi)型的具有優(yōu)異的氧還原電催化活性多孔碳,對(duì)于提高氧還原反應(yīng)效率具有一定的研究?jī)r(jià)值。
[Abstract]:It is the trend of science and technology to develop full fuel cells instead of traditional electrochemical cells.The reason why fuel cells are not used in large-scale production is mainly due to the kinetic inertia of the cathode reaction of the fuel cell itself. The cathode of the fuel cell mainly takes place in oxygen reduction reaction, which involves gas diffusion, adsorption, electron transfer.Product diffusion and so on, is a complex process.Therefore, it is very important to increase the rate of cathodic oxygen reduction reaction and to use efficient electrocatalysts.In the process of continuous research and exploration, the researchers found that Pt based catalyst is the most effective electrocatalyst for oxygen reduction at present.However, Pt-based electrocatalysts are restricted by the stability and the influence of fuel crossover, such as CO poisoning, etc. Moreover, Pt itself belongs to precious metal, which has low content and high cost in the crust, which is not conducive to large-scale commercial production.Therefore, it is very important to find cheaper electrocatalysts to replace Pt.The metal-organic skeleton materials have the following characteristics, such as the selectivity of metal and ligands, large specific surface area, high porosity and adjustable pore size, and high carbon content.鏈枃鍒╃敤閲戝睘鏈夋満楠ㄦ灦浣滀負(fù)鍓嶉┍浣，

本文編號(hào)：1711544