Karbon Keçe Elektrotun Alkali Ortamda Elektrokatalitik Hidrojen Çıkış Etkinliğinin Artırılması

Bu çalışmada, karbon keçe üzerine bakır, kobalt, kobalt-bakır ve kobalt/platin elektrokimyasal olarak çöktürülmüştür. Hazırlanan elektrotların 1 M KOH çözeltisinde hidrojen gazı çıkışına katalitik etkisi katodik akım-potansiyel eğrileri, elektrokimyasal impedans spektroskopisi (EIS) ve elektroliz yöntemleri kullanılarak incelenmiştir. Hazırlanan elektrotların zamanla kararlılık testi 1 M KOH çözeltisi içinde 2,2x10-3 A m-2’lik akım yoğunluğunda araştırılmıştır. Elde edilen sonuçlara göre karbon keçe üzerine, kobalt, kobalt-bakır ve kobalt/platin çöktürülmesi elektrotun aşırı gerilimini düşürerek hidrojen gazı çıkışını arttırmaktadır. Elektrotun katalitik etkinliği çöktürülen metalin türüne bağlıdır. Katalitik etkinliğin artması keçe elektrotun büyük yüzey alanı ve kobalt ile platinin yüksek katalitik etkinliği ile açıklanabilir.

Anahtar Kelimeler:

Karbon keçe, Kobalt çöktürme, Elektrokataliz, Elektroliz, Hidrojen

Enhancement of Electrocatalytic Hydrogen Evolution Activity of Carbon Felt in Alkaline Media

In this study, copper, cobalt, cobalt-copper and cobalt/platinum were electrochemically deposited over a carbon-felt electrode. The electrocatalytic activity of the prepared electrodes for the hydrogen gas evolution was studied in 1 M KOH solution using cathodic current-potential curves, electrochemical impedance spectroscopy (EIS) and electrolysis techniques. The long-term stability of the prepared electrodes was investigated at 2.2x10-3 A m-2 in 1 M KOH solution. It was found that, the electrodeposition of the copper, cobalt, cobalt-copper and cobalt/platinum over the carbon-felt increases hydrogen gas evolution by decreasing discharge potential. The electrocatalytic activity of the electrode depends on the kind of metal. The electrocatalytic activity of deposited electrodes can explain by high surface area of the carbon felt and high catalytic activity of the cobalt and platinum.

Keywords:

Carbon felt, Cobalt deposition, Electrocatalaysis, Electrolysis, Hydrogen,

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