Hiệu suất của pin nhiên liệu methanol lỏng

Pin nhiên liệu Methanol lỏng (DMFC) là một thiết bị điện hóa, nó có thể chuyển hóa trực tiếp năng lượng hóa học (ở đây là năng lượng hóa học của Methanol lỏng) thành năng lượng điện. Pin DMFC được nghiên cứu trong trường hợp này có chất xúc tác sử dụng cho cực Anode là bột Ru-Pt khối lượng sử dụng là 4mg/cm2. Còn chất xúc tác dùng cho cực Cathode là bột Pt, khối lượng sử dụng là 2mg/cm2. Màng trao đổi Proton được sử dụng cho Pin DMFC là màng Nafion 117. Hiệu suất của Pin DMFC được đánh giá thông qua các điều kiện như nồng độ của Methanol và nhiệt độ của Pin.
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Hiệu suất của pin nhiên liệu methanol lỏng Hdi nghi Khoa hgc ky niem 35 ndm Viin Khoa hgc vd Cdng nghi Viet Nam - Hd Ndi 10/2010 HIEU S U A T CUA PIN NHIEN LIEU METHANOL LONG Nguyen Lu-dng Lam, Nguyin Trong TTnh Institute of Applied Physics and Scientific Instmment 18 - Hoang Qudc Viet, Ciu Giiy, Ha Ndi Email: nllaml95(a),vahoo.com Tom tat: Pin nhien lieu Methanol Idng (DMFC) Id mot thiit bi diin hda, nd cd thi chuyin hda true tiip ndng lugng hda hoc (d ddy Id ndng lugng hda hoc ciia Methanlo Idng) thdnh ndng lugng dien. Pin DMFC dugc nghien cieu trong trudng hgp ndy cd chdt xiic tdc su dung cho cue Anode Id bdt Ru-Pt khdi lugng sit dung Id 4mg/cm2. Cdn chdt xuc tdc dimg cho cue Cathode Id bdt Pt, khdi lugng sit dung Id 2mg/cm2. Mdng trao ddi Proton dugc sit dung cho Pin DMFC Id mdng Naflon 117. Hiiu sudt cita Pin DMFC dugc ddnh gid thdng qua cdc diiu kiin nhu ndng do cita Methanol vd nhiet do cita Pin. Key words: DMFC, Ru-Pt, Pt, Naflon 117 Abstract: Direct Methanol Fuel Cell (DMFC) is an electrochemical device that can converts Methanol chemical energy to electrical energy directly. DMFC was studied in this case as Catalyst for anode is Ruthenium-Platinum powders and catalyst loading is 4mg/cm^. Catalyst for cathode is Platinum powder; catalyst loading is 2mg/cm . In this case proton membrane is Naflon 117. Performance will be discussed in terms of Methanol concentration and cell temperature. . INTRODUCTION At the beginning of the 21 century, the conversion of chemical energy into electrical energy became more important due to the increase in the use of electricity. One of the major factors that have influenced the development of fiiel cells has been the increasing concern about the environmental consequences of fossil fuel in production of electricity and for the propulsion of vehicles. The dependence of the industrialized countries on oil became apparent in the oil crises. One type of fiiel cells as a Direct Methanol Fuel Cells may help to reduce our dependence on fossil fuel and diminish poisonous emissions into the atmosphere, since they have higher electrical efficiencies compared to heat engines. A Direct Methanol Fuel Cell (DMFC) is defined as an electrochemical device that can continuously convert chemical energy (Methanol) into electrical energy directly. Much like a battery, a fiiel cell produces electrical energy. However, unlike battery, reactants eire supplied continuously and products are continuously removed. The Direct Methanol Fuel Cell (DMFC) has been studied due to many merits: Methanol is a high energy fuel; a clean power is produced at low operating temperatures; membranes last longer due to operating in aqueous environment; reactant humidification is not required; the DMFC system has faster response and is smaller in volume [1-2]. 407 Tiiu ban: Mdi tru&ng vd Ndng hcgng ISBN: 978-604-913-013-7 In a direct methanol fuel cell (DMFC), methanol is oxidized at the anode and oxygen (usually in air) is reduced at the cathode [1]. The electrochemical oxidation of methanol (in acid electrolyte) occurs as follows: Anode reaction: CH3OH + H2O => CO2 +6H^ + 6e Cathode reaction: 3/2O2 + 6H +6e => 3H2O Overall cell reaction: CH3OH +3/2O2 => CO2 + 2H2O In this report, we present of performance of the direct methanol fuel cells have 5 cm active areas. An anode catalyst is commercial Ru-Pt powders and a cathode catalyst is commercial Pt powder. 2. EXPERIMENTAL Preparation of diffusion layers: A carbon paper was used as a diffusion layer. Thickness of carbon paper is 0.2 mm. The dimensions are 2.23cmx2.23cm (5cm activity area). The diffusion processes facilitated a role of catalysts adhered on its surface. Preparation of anode catalyst: a catalyst material for anodes in this work that is PtRu black powder (50:50 atom ratios, Johnson Matthey Corp.). The catalyst was well-dispersed with 5% Nafion solution (Dupont) for 30 minutes, leading to a solution, namely, a catalyst ink. The catalyst ink was painted into a surface of a 5cm^ carbon paper (dimensions 2.23x2.23cm) with the catalyst loading of about 4mg/cm^. The catalyst/carbon paper was dried at room temperature before being assembled to a MEA (membrane electrolyte assembly). Preparation of cathode catalyst as same the way of anode but a catalyst for cathode only Pt powder and the catalyst loading is 2mg/cm^ (Johnson Matthey Corp.). Treatment of Nafion 117 membrane: a membrane is very crucial to the DMFCs electrode. It is c ...