Sains Malaysiana 48(6)(2019): 1221–1231

http://dx.doi.org/10.17576/jsm-2019-4806-09

Analisis Tenaga Bebas dan Sifat Mangkin PtRuFeNi untuk Sel Fuel Metanol Langsung (DMFC) Tunggal

(Analysis of Free Energy and Behaviour of PtRuFeNi Catalyst for Single Direct Methanol Fuel Cell (DMFC))

SAHRIAH BASRI^1* & SITI KARTOM KAMARUDIN^1,2

¹Fuel Cell Institute, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor Darul Ehsan, Malaysia

²Department of Chemical and Process, Faculty of Engineering & Built Environment, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor Darul Ehsan, Malaysia

Diserahkan: 16 November 2018/Diterima: 6 Mac 2019

ABSTRAK

Mangkin dwilogam PtRu adalah mangkin konversional yang biasa digunakan untuk aplikasi sel fuel metanol langsung (DMFC). Walau bagaimanapun, kadar tindak balas pengoksidaan metanol (MOR) yang rendah menjadi kekangan yang ketara kepada penurunan prestasi dan kuasa DMFC. Kos PtRu yang sangat mahal menghalang DMFC untuk dikomersialkan yang setanding bateri. Maka, muatan PtRu dikurangkan dan logam alternatif perlu ditambah bagi memastikan prestasi DMFC dikekalkan. Justeru, objektif utama kajian ini adalah menganalisis logam alternatif yang berpotensi untuk dijadikan sebagai mangkin. Empat mangkin berpotensi iaitu ferum (Fe), nikel (Ni), aurum (Au) dan paladium (Pd) disimulasikan dengan Pt dan Ru menggunakan kaedah kimia pengkomputeran. Perisian Material Studio digunakan untuk menganalisis tenaga bebas dan tenaga penjerapan. Analisis kajian ini menemui bahawa logam ferum (Fe) dan nikel (Ni) memiliki prestasi yang sama dengan Pt dan Ru. Sel tunggal DMFC kemudian dibangunkan dengan menggunakan nanomangkin PtRuFeNi yang disokong dengan tiub nano karbon (MWCNT). Prestasi sel tunggal DMFC yang dihasilkan menggunakan mangkin PtPtRuFeNi/MWCNT adalah 11 mW dengan ketumpatan arus optimum sebanyak 33 mA.cm-2.

Kata kunci: Sel fuel metanol langsung; tenaga bebas; tiub nano karbon

ABSTRACT

Bimetallic PtRu catalysts is a conventional anode catalyst commonly used for direct methanol fuel cell application (DMFC). However, the low methanol oxidation reaction (MOR) rate has been a significant constraint to the DMFC performance and power output. Besides, expensive PtRu prevents DMFCs from being commercially as compare to batteries. Therefore, PtRu catalyst loading needs to be reduced and alternative metal should be added to ensure DMFC performance is maintained. Hence, the main objective of this study was to analyze potential alternative catalysts metals. Four potential catalysts, ferum (Fe), nikle (Ni), aurum (Au) and palladium (Pd) were simulated using computational chemistry. Material Studio software used to analyse free energy analysis and adsorption energy. The analysis using Material Studio software showed that the ferum (Fe) and nickel (Ni) had the same performance as Pt and Ru. Then, DMFC single cell was fabricated using PtRuFeNi nanocatalyst supported with multi -walled carbon nanotube (MWCNT) and found high DMFC performance compared to PtRu catalysts. The performance of single cell DMFC produced by PtRuFeNi/MWCNT nanocatalyst is 11 mW with optimum current density of 33 mA.cm-2.

Keywords: Carbon nanotube; direct methanol fuel cell (DMFC); free energy

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*Pengarang untuk surat-menyurat; email: sahriah@ukm.edu.my