本文選題：析氧反應(yīng) + 銅基催化劑　； 參考：《西南石油大學(xué)》2017年碩士論文

【摘要】：在高效的水分解體系中,具備高活性、出色穩(wěn)定性以及低過電位的催化劑是必不可少的。從貴金屬到過渡金屬氧化物,雖然不計其數(shù)的均相與異相催化劑已經(jīng)被嘗試用于減小析氧半反應(yīng)(OER)較高的過電位,但在探尋高效、低廉的OER催化劑的這條道路上依然充滿著未知與挑戰(zhàn)。銅是一種非常廉價的金屬元素,其各種形式的化合物在化學(xué)、生物等領(lǐng)域顯示出良好的催化性能。本論文從元素?fù)诫s與表面修飾兩方面著手進(jìn)行銅基催化劑的制備,并研究其在OER中的電催化性能。論文利用陽極沉積法成功制得了CuNiOx與CuCoOx薄膜。利用SEM、XRD對催化劑形貌、結(jié)構(gòu)進(jìn)行表征,證明該薄膜為非晶結(jié)構(gòu)。電化學(xué)性能測試結(jié)果表明,在不同體系中CuNiOx與 CuCoOx樣品的OER催化活性均優(yōu)于CuO樣品,通過對沉積時間、沉積方式、元素比例以及體系pH的優(yōu)化,得到在碳酸體系中樣品CuNiOx(4:1)性能最優(yōu),其OER起始過電位為320 mV,在電流密度為5 mA/cm2下,可持續(xù)催化10 h以上。XPS結(jié)果顯示,二元氧化物樣品中氧缺陷含量成倍增加,該基團(tuán)可加快電子向吸附物質(zhì)的傳遞速率進(jìn)而提升OER催化活性。同時,論文還利用化學(xué)刻蝕法成功制備了原位生長的自支撐CuO/CF(泡沫銅)電極。經(jīng)SEM、XRD測試表明不同煅燒溫度下的催化劑形貌以及晶體結(jié)構(gòu)存在明顯差異。電化學(xué)性能測試結(jié)果表明,煅燒溫度為500 ℃時的CuO/CF顯示出最好的OER性能,在1.8 V(vs.RHE)電位下最大電流密度達(dá)到90 mA/cm2,優(yōu)于目前文獻(xiàn)報道的結(jié)果,其卓越的OER催化性能主要歸功于極高的表面積,電催化活性面積(ECSA)測試結(jié)果顯示,處理后的催化劑表面積增加了約3倍。除此之外,該方法原位生成的CuO膜對CF骨架形成保護(hù),有效抑制了 CF在高電位下的降解,增強(qiáng)了催化劑的使用壽命。
[Abstract]:In an efficient water decomposition system, catalysts with high activity, excellent stability and low overpotential are essential. From precious metals to transition metal oxides, although countless homogeneous and heterogeneous catalysts have been tried to reduce the high overpotential of oxygen evolution half-reaction, they are looking for high efficiency. The path of cheap OER catalyst is still full of unknown and challenges. Copper is a very cheap metal element, its various forms of compounds in chemical, biological and other fields show good catalytic performance. In this paper, the preparation of Cu-based catalysts was carried out from the aspects of element doping and surface modification, and their electrocatalytic properties in OER were studied. In this paper, CuNiOx and CuCoOx thin films were successfully prepared by anodic deposition. SEM XRD was used to characterize the morphology and structure of the catalyst. It was proved that the film was amorphous. The results of electrochemical performance test showed that the OER catalytic activity of CuNiOx and CuCoOx samples was superior to that of CuO samples in different systems. The deposition time, deposition mode, element ratio and pH of the system were optimized. The results showed that the initial overpotential of OER was 320 MV, and the oxygen defect content in the binary oxide sample increased exponentially when the current density was 5 mA/cm2 and the catalytic activity was more than 10 h, the results showed that CuNiOx4: 1) had the best performance in the system of carbonated acid, and the initial overpotential of CuNiOx4: 1 was 320 MV. The group can accelerate the transfer rate of electron to the adsorbent and then enhance the catalytic activity of OER. At the same time, the self-supporting CuO / CF (foamed copper) electrode was successfully prepared by chemical etching in situ. The SEM XRD results show that the morphology and crystal structure of the catalysts are different at different calcination temperatures. The results of electrochemical performance test showed that CuO/CF with calcination temperature of 500 鈩，

本文編號：1776814