【摘要】：金屬空氣燃料電池是非常有前景的動力源，它不經(jīng)過卡諾循環(huán)直接把化學(xué)能轉(zhuǎn)化為電能，它的理論電壓高、比能量高、成本低、與環(huán)境相容性好，因此受到極大的關(guān)注。在金屬空氣電池中，陰極上的催化劑起到催化氧還原反應(yīng)作用，是影響電池性能的關(guān)鍵因素。由于簡單的單體卟啉類催化劑催化活性相對較低，穩(wěn)定性差，在此基礎(chǔ)上， 我們用新工藝設(shè)計并合成了金屬聚合卟啉類催化劑（PTPPM/C）。用紅外光譜和紫外光譜表征了金屬聚合卟啉的結(jié)構(gòu)，結(jié)果表明，所合成的產(chǎn)物為目標化合物。用差熱分析（TG）聯(lián)合紫外光譜，對聚合卟啉的熱穩(wěn)定性進行研究。結(jié)果顯示，金屬聚合卟啉在600℃以下并不分解，具有良好的熱穩(wěn)定性。將PTPPM固載到活性炭表面得到PTPPM/C催化劑，用旋轉(zhuǎn)圓盤電極（RDE）和電化學(xué)工作站探究催化劑的最佳制備工藝條件，結(jié)果表明兩類催化劑（PTPPPt/C，，PTPPPd/C）的最佳制備參數(shù)相同：活化溫度600℃，MN4載量6wt%。最佳制備參數(shù)下得到的PTPPPt/C和PTPPPd/C催化劑在氧氣飽和的0.5mol/L的H2SO4溶液中，其初始還原電位分別為0.85，0.84Vvs.RHE，轉(zhuǎn)移電子數(shù)分別為3.85和3.83。用TEM、XRD和XPS對催化劑表面形貌狀態(tài)，微觀結(jié)構(gòu)和催化劑組成價態(tài)做了研究。測試結(jié)果顯示，當(dāng)金屬聚合卟啉催化劑在600℃均勻負載到活性碳的表面，催化劑為無定形結(jié)構(gòu)，催化活性中心為在卟啉環(huán)中的金屬離子。金屬空氣電池陰極催化層中催化劑活性中心MN4為1mg/cm2。分別對空氣電極和金屬空氣電池進行研究。從電流-電位曲線和功率曲線可以得出：PTPPM/C催化劑是一種高性能的金屬空氣電池陰極催化劑，其性能與Pt/C催化劑較接近。恒電流不間斷放電電池穩(wěn)定性測試表明，連續(xù)500min放電，金屬空氣電池性能 幾乎不衰減，說明PTPPM/C催化劑催化的金屬空氣電池具有穩(wěn)定的放電性能。
[Abstract]:Metal air fuel cell is a very promising power source. It converts chemical energy into electric energy directly without Carnot cycle. It has high theoretical voltage, high specific energy, low cost and good compatibility with the environment, so it has received great attention. In metal air batteries, the catalyst on the cathode plays a catalytic role in oxygen reduction, which is the key factor affecting the performance of metal air batteries. Because of the relatively low catalytic activity and poor stability of simple monomer porphyrin catalysts, we designed and synthesized metal polymeric porphyrin catalysts (PTPPM/C) by a new process. The structure of metallopolytoporphyrin was characterized by IR and UV spectra. The results showed that the synthesized product was the target compound. The thermal stability of polyporphyrin was studied by differential thermal analysis (TG) combined with ultraviolet spectroscopy. The results show that metalloporphyrins do not decompose below 600 鈩

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