利用矽泥廢料回收物製備甲醇氧化之複合觸媒與其特性研究

Preparation of composite catalysts with the recovered materials from silicon slurry waste and their characteristics for electrocatalytic methanol oxidation

林譽陞(Yu-Sheng Lin)

指導教授 ： 蔡子萱

國立臺北科技大學/工程學院/資源工程研究所/碩士(2014年)

https://doi.org/10.6841/NTUT.2014.00712

摘要

直接甲醇燃料電池常使用複合觸媒作為陽極，進行甲醇電催化反應，並常以多元醇還原法合成該金屬複合觸媒。本研究探討利用矽泥廢料回收物製備甲醇電催化複合觸媒與其特性。實驗結果發現使用不同二醇類分子作為還原劑與使用的載體為C、C/Si或C/富矽粉體，均可成功地將Pt還原在載體上，且Pt晶粒大小約8 nm~12 nm。對所合成的複合粉體進行Pt定量發現，於Pt/C/Waste Si及Pt/C/Si系列觸媒中的Pt含量比Pt/C系列觸媒高。在測試催化甲醇氧化反應效能上，比較各載體循環伏安圖之第一正向氧化峰電流發現，使用Pt/C/Si有最高電流，其次是Pt/C/Waste Si；而Pt/C最低，顯示Pt/C/ Waste Si 及Pt/C/Si 對甲醇氧化催化效果均較Pt/C好。另外，由正向與逆向氧化峰電流比值趨勢發現，使用Pt/C/Si有最高電流比值，可說明此種觸媒較能將甲醇氧化完全，或較不易受氧化中間物毒化；其次是 Pt/C；而Pt/C/Waste Si較低；由阻抗分析結果也發現添加矽的觸媒有較佳的抗毒化能力，顯示Si表面富集OH基的能力確實有助於氧化吸附在Pt上的中間物，進而提升甲醇氧化效率。研究亦利用原位傅立葉轉換紅外線吸收光譜分析甲醇氧化的反應過程，發現相關吸收峰的改變。本研究證實自矽泥廢料回收所獲得的二醇類切割液能作為多元醇還原法中的還原劑使用；所回收的富矽粉體能作為金屬觸媒製作的載體，提高觸媒抗毒化能力。

關鍵字

陽極觸媒 ； 聚二醇 ； 多元醇還原法 ； 甲醇 ； 矽泥廢料

並列摘要

Composite catalysts which are synthesized via polyol reduction method, are most commonly used as anode electrocatalysts for the electro-oxidation of methanol in DMFC. This study investigated the preparation of composite catalysts using the recovered materials from silicon slurry waste and their characteristics for electrocatalytic methanol oxidation. The experimental results indicate nano-sized Pt could be produced on C, C/Si or C/Waste Si successfully by use of various glycols as reducing agent, and the Pt content in Pt/C/Waste Si or Pt/C/Si is higher than that in Pt/C.The cyclic voltammograms for electro-oxidation of methanol show the forward peak current density using Pt/C/Si or Pt/C/Waste Si is higher than that using Pt/C, indicating the better electrocatalytic oxidation of methanol by Pt/C/Waste Si and Pt/C/Si. Furthermore, the ratio of the forward to reverse peak current density shows the highest ratio was obtained by Pt/C/Si, indicating Pt/C/Si could make higher oxidation degree of methanol and have better anti-poisoning ability. Impedance results also show the addition of Si could increase the anti-poisoning ability of anode electrocatalysts for oxidation of methanol, due to OH groups on Si surface. These OH groups would enhance the oxidation of intermediates adsorbed on Pt, and then increase the efficiency of methanol oxidation. The behaviors of methanol oxidation reaction, including the change of functional groups, were explored by in-situ Fourier transform infrared spectroscopy. This study demonstrated that the recovered materials from silicon slurry waste could be applied to the preparation of composite catalysts. The recovered glycol cutting liquids could be used as reducing agents to prepare Pt/C catalysts by polyol reduction method, and the recovered silicon-rich powders could be used as a catalyst support for further enhancing anti-poisoning ability.

並列關鍵字

Anode catalyst ； Glycols ； Polyol reduction method ； Methanol ； Silicon slurry waste

參考文獻

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