【摘要】：氫氧電催化反應(yīng)是氫能源體系的重要反應(yīng),其熱力學(xué)和動力學(xué)直接影響水解制氫和燃料電池的能量效率和功率密度.過去十多年來,基于量子化學(xué)的理論計算在電催化劑設(shè)計及電催化反應(yīng)機理研究中得到廣泛應(yīng)用.結(jié)合文獻結(jié)果,本文介紹了近年來在Pt基催化劑表面氫、氧電催化反應(yīng)理論計算研究中獲得的結(jié)果和認(rèn)識.在研究中重點對反應(yīng)中間體吸附結(jié)構(gòu)、覆蓋度及其對反應(yīng)路徑和動力學(xué)的影響機制進行了分析.結(jié)果指出,反應(yīng)中間體的吸附特性不僅會影響反應(yīng)控制步驟的活化能,同時通過改變表面反應(yīng)活性位的結(jié)構(gòu)和數(shù)量影響表面反應(yīng)速率.對火山頂點附近的Pt基催化劑,簡單計算的吸附能不足以準(zhǔn)確預(yù)測催化劑活性,必須考慮吸附質(zhì)的覆蓋度和吸附結(jié)構(gòu)的影響.在此認(rèn)識基礎(chǔ)上,根據(jù)表面反應(yīng)自由能及速率與關(guān)鍵中間體吸附能、覆蓋度及電極電勢的關(guān)系建立微觀動力學(xué)模型,利用密度泛函理論計算獲得關(guān)鍵吸附中間體在催化劑表面的電化學(xué)吸附等溫線(吸附結(jié)構(gòu)及覆蓋度與電極電勢的關(guān)系),確定反應(yīng)活性位、反應(yīng)路徑和動力學(xué),構(gòu)建催化活性與吸附能的關(guān)系曲線,預(yù)測催化劑的表面結(jié)構(gòu)及尺寸效應(yīng),并對一些重要實驗結(jié)果進行解釋.
[Abstract]:Hydrogen-oxygen electrocatalytic reaction is an important reaction in hydrogen energy system. Its thermodynamics and kinetics directly affect the energy efficiency and power density of hydrogen production and fuel cell. In the past decade, theoretical calculations based on quantum chemistry have been widely used in the design of electrocatalysts and the study of electrocatalytic reaction mechanism. Based on the results of literature, this paper introduces the results and understandings obtained in the theoretical calculation of surface hydrogen and oxygen electrocatalytic reactions of Pt catalysts in recent years. In the study, the adsorption structure, coverage and the mechanism of reaction path and kinetics of the reaction intermediates were analyzed. The results show that the adsorption characteristics of the reaction intermediates not only affect the activation energy of the reaction control steps, but also affect the surface reaction rate by changing the structure and quantity of the active sites of the surface reaction. For the Pt based catalyst near the peak of the volcano, the calculated adsorption energy is not enough to predict the activity of the catalyst accurately. The influence of the coverage of adsorbate and the adsorption structure must be considered. On the basis of this understanding, a micro kinetic model was established according to the relationship between the free energy and rate of surface reaction and the adsorption energy, coverage degree and electrode potential of the key intermediates. The electrochemical adsorption isotherms of the key adsorbed intermediates on the catalyst surface were obtained by using density functional theory (the relationship between the adsorption structure and the coverage degree and the electrode potential), and the reactive sites, reaction paths and kinetics were determined. The relationship curve between catalytic activity and adsorption energy was constructed, the surface structure and size effect of catalyst were predicted, and some important experimental results were explained.
【作者單位】： 湖北省化學(xué)電源重點實驗室武漢大學(xué)化學(xué)與分子科學(xué)學(xué)院;
【基金】：國家自然科學(xué)基金(編號:21673163,21073137) 國家重點基礎(chǔ)研究發(fā)展計劃(編號:2012CB932800)資助項目
【分類號】：O643.36

【相似文獻】

相關(guān)期刊論文 前5條

1 萬本強,羅維忠,吳婉群;催化電合成聚吡咯膜對抗壞血酸的電催化反應(yīng)的研究[J];西南師范大學(xué)學(xué)報(自然科學(xué)版);1993年03期

2 宋海華,鄔慧雄,馬海洪;燃料電池技術(shù)在電催化反應(yīng)領(lǐng)域的應(yīng)用[J];化學(xué)進展;2004年03期

3 陳震;固體聚合物電解質(zhì)在肉桂醇電解氧化中的應(yīng)用(Ⅱ)——后續(xù)化學(xué)反應(yīng)在電催化反應(yīng)中的地位及其影響因素[J];物理化學(xué)學(xué)報;1993年03期

4 劉秉濤;宋海燕;李國亭;;氧化性物種在光電催化反應(yīng)中的產(chǎn)生和利用[J];華北水利水電學(xué)院學(xué)報;2012年03期

5 ;[J];;年期

相關(guān)會議論文 前3條

1 孫世剛;;微觀尺度電催化:從原子排列結(jié)構(gòu)明確的單晶表面到納米結(jié)構(gòu)表面體系[A];第十三次全國電化學(xué)會議論文摘要集（上集）[C];2005年

2 孫世剛;;微觀尺度電催化:從原子排列結(jié)構(gòu)明確的單晶表面到納米結(jié)構(gòu)表面體系[A];第十三次全國電化學(xué)會議論文摘要集（上集）[C];2005年

3 褚道葆;張秀梅;張莉艷;尹曉娟;姚文俐;;基于納米TiO_2膜的異相電催化反應(yīng)[A];第十三次全國電化學(xué)會議論文摘要集（上集）[C];2005年

相關(guān)博士學(xué)位論文 前1條

1 杜世超;鐵系金屬化合物電催化分解水制氧性能及機制研究[D];吉林大學(xué);2016年

相關(guān)碩士學(xué)位論文 前2條

1 王歡;基于含酚廢水處理的改性MnO_x/Ti電催化膜的研究[D];天津工業(yè)大學(xué);2016年

2 呂亞芬;多壁碳納米管電極的制作、表征及其對生物分子的電催化[D];南京師范大學(xué);2006年

，

本文編號：2233077