Doğrudan Metanol Yakıt Pili Anot Katalizörlerinin Sentezi ve Geliştirilmesi

Günümüzde doğrudan beslemeli yakıt pilleri kolay taşınabilirlik, yakıt ikmali ve yüksek enerji dönüşümü gibi avantajları yüzünden en çok çalışılan konular arasında yer almaktadır. Pt küçük organik moleküllerin sentezinde iyi bir katalizördür fakat Pt yakıt pillerinin çalıştığı düşük sıcaklıklarda oluşan CO gazı ile bu koşullarda zehirlenir. Doğrudan beslemeli metanol yakıt pilleriyle yapılan çalışmalarda Pt-Ru katalizörünün iyi bir metanol yakıt pili katalizörü olduğu rapor edilmiştir fakat Ru eklendiğinde katalizörün aktivesinin neden ve nasıl arttığı halen cevaplanamamıştır. Bu soruların yanıtlanabilmesi için yeni nesil aktif katalizörlerin hazırlanması, zehirlenme gibi mevcut problemlerin aşılmasında büyük önem taşımaktadır. Bu çalışma, metanol yakıt pili anot katalizörlerinin aktivitelerinin araştırılması için yapılmıştır. Katalizörler sıralı indirgenme yöntemi hazırlanmış ve katalizör hazırlama yönteminin metanol elektrooksitlenme aktivitesine etkisi araştırılmıştır. Sonuçlar, Pt@Ru/C ve Ru@Pt/C katalizörler üzerinde yapılan ölçümlerde Pt@Ru/C katalizörlerin daha yüksek aktivite gösterdiği gözlemlenmiştir.

Anahtar Kelimeler:

metanol, yakıt pili, katalizör, sıralı indirgeme, platin

Sequential Reduction Synthesis and Development of Carbon Supported Pt-Ru Direct Methanol Fuel Cell Anode Catalysts

Nowadays, direct fueled fuel cells are among the most studied subjects due to their advantages such as easy portability, refueling and high energy conversion. Pt is a good catalyst for the synthesis of small organic molecules, but Pt is poisoned by the CO gas generated at the low temperatures that the fuel cells operate. It has been reported in the studies about direct methanol feed fuel cell that Pt-Ru catalyst is a good methanol fuel cell catalyst, but when Ru is added, why and how the catalytic activity is increased is still unanswered. In order to answer these questions, preparation of new generation active catalysts is crucial for overcoming existing problems such as poisoning. This work was done to investigate the activities of methanol fuel cell anode catalysts. The catalyts were prepared via sequential reduction method and the effect of catalyst preparation method on methanol electrooxidation activity was investigated. In the measurements performed on carbon supported Rushell-Ptcore (Pt@Ru/C) and Ptshell-Rucore (Ru@Pt/C) catalysts, the results show Ru@Pt/C catalyst having higher activity.

Keywords:

methanol, fuel cell, catalyst, sequential reduction, platinum,

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