Synthesis of active platinum particles on the activated carbon with sodium borhydride as reduction agent

Öz

Platinum nanoparticles on the activated carbon surface were obtained by chemical reduction of hexachloroplatinic acid (H2PtCl6) with different reducing agents. Sodium borohydride, formic acid and formaldehyde were chosen as reducing agents. In this study, the effects of the reducing agent on the uniform distribution and structure of platinum particles on activated carbon were investigated. The morphology and microstructure of the obtained products were characterized by SEM, phase characterization by XRD and surface area and pore distributions by BET method. The obtained results showed that the use of sodium borohydride as a reducing agent provides optimum conditions for obtaining homogeneous platinum nanoparticles on the activated carbon surface.

Anahtar Kelimeler

• Pt particle
• chemical reduction
• fuel cell catalyst

İndirgeyici ajan olan sodyum borhidrür ile aktif karbon yüzeyinde aktif platin parçacıklarının sentezi

Öz

Aktif karbon yüzeyinde platin nanopartiküller, hekzakloroplatinik asidin (H2PtCl6) farklı indirgenlerle kimyasal indirgenmesiyle elde edilmiştir. İndirgeyici ajan olarak sodyum borhidrür, formik asit ve formaldehit seçilmiştir. Bu çalışmada platin parçacıklarının aktif karbon yüzeyindeki dağılımı ve yapısı üzerinde indirgeyici ajan seçiminin etkileri incelenmiştir. Elde edilen ürünlerin morfolojisi ve mikro yapısı taramalı elektron mikroskobu (SEM), faz karakterizasyonu X ışını kırınım spektrometre (XRD) ve yüzey alanı ile gözenek boyut dağılımları azot adsorpsiyon izoterminden BET yöntemi ile hesaplanarak belirlenmiştir. Elde edilen sonuçlar, indirgeyici ajan olarak sodyum borhidrürün kullanımının aktif karbon yüzeyinde homojen platin nanoparçacıklarının eldesi için optimum koşullar sunduğunu göstermiştir.

Anahtar Kelimeler

• Pt parçacık
• kimyasal indirgeme
• yakıt pili katalizör

Kaynakça

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