IN THIS STUDY, IN ORDER TO REACH A NEW SUITABLE ELECTROLYTE FOR BETTER METHANOL ELECTRO-OXIDATION IN ACIDIC MEDIA, SOLUTION CONTAINING SYNTHETIC MODIFIER (SM) WAS USED. THESE SMS HAVE HIGH THERMAL STABILITY AND EXCELLENT IONIC CONDUCTIVITY WHICH HAS CONDUCTIVITY ABOUT 0.1 S/CM. THE METHANOL OXIDATION WAS MONITORED ON MODIFIED GC ELECTRODE WITH 10-20 %WT PT-RU/C WHICH HAS PT AND RU LOADING OF 0.051 MG/CM2 AND 0.102 MG/CM2, RESPECTIVELY. SMS IMPROVE THE METHANOL OXIDATION REACTION KINETIC BY INCREASING THE SOLUTION IONIC CONDUCTIVITY AND ALSO DECREASE THE RCT OF REACTION. THEREFORE, SM ADDED ELECTROLYTE CAN BE THE NEW PROMISING ELECTROLYTE FOR DMFCS APPLICATION.

IN RECENT YEARS, UTILIZATION OF IONIC LIQUIDS (ILS) AS ELECTROLYTE ADDITIVES IS CONSIDERED AS A NEW TOPIC IN STUDIES OF FUEL CELLS AND BATTERIES. ILS ARE MOLTEN SALTS AT AMBIENT TEMPERATURE WHICH HAVE CONSIDERABLE POTENTIAL AS HIGH TEMPERATURE ELECTROLYTE MODIFIERS DUE TO THEIR UNIQUE PROPERTIES SUCH AS NON-VOLATILITY, HIGH IONIC CONDUCTIVITY, NON-FLAMMABILITY AND HIGH THERMAL STABILITY. IN THIS WORK, EFFECT OF ILS STRUCTURE ON THE PERFORMANCE OF DMFCS ANODE HAS BEEN STUDIED BY DIFFERENT ELECTROCHEMICAL METHODS SUCH AS CYCLIC VOLTAMMETRY (CV) AND ELECTROCHEMICAL IMPEDANCE SPECTROSCOPY (EIS). THE RESULTS SHOW THAT WITH INCREASING OF ALKYL CHAIN OF IL CATION, THE ELECTRO ACTIVITY OF CATALYST DECREASE IN METHANOL OXIDATION REACTION RELATED TO THE STRICE HINDRANCE OF IL CATION. A POSSIBLE EXPLANATION IS THAT WITH INCREASING THE NUMBER OF ALKYL CHAIN, BULK RESISTANCE INCREASED AND PROTON TRANSFER TO THE CATALYST SURFACE DECREASES AS WELL. FINALLY BY ANALYZING TEST RESULTS IT COULD BE CONCLUDED AT LOW TEMPERATURE ILS DOES NOT HAVE ANY PROMISING EFFECT ON THE CATALYST ACTIVITY AND THE ROLE OF ILS BECAME IMPORTANT AT HIGHER TEMPERATURES.

IN SPITE OF HIGH POWER DENSITY AND HIGH ENERGY CONVERSION EFFICIENCY OF FUEL CELLS, IN THE PATH OF WIDESPREAD COMMERCIALIZATION, THE POLYMER ELECTROLYTE MEMBRANE FUEL CELL (PEMFC) IS ENCOUNTERED WITH A NUMBER OF CHALLENGING SUCH AS HIGH PERFORMANCE AND DURABILITY [1]. ...

FUEL CELLS HAVE BEEN EXTENSIVELY STUDIED OVER THE LAST FIVEDECADES AND INCREASING RESOURCES HAVE BEEN USED TO BRING THEM TO A COMMERCIAL STAGE AND TO DEVELOP ALTERNATIVE FUELS TO HYDROGEN.AS PROMISING POWER SOURCES FOR SPACE AND UNDERWATER APPLICATIONS, DIRECT BOROHYDRIDE–HYDROGEN PEROXIDE FUEL CELLS (DBHPFCS), COMPRISED OF BH OXIDATION AT THE ANODE AND H O REDUCTION AT THE CATHODE, HAVE ATTRACTED INCREASING ATTENTIONS RECENTLY [1-6].IN THIS STUDY, PT/C (20 WT.%) CATHODE AND PT-NI (1: 1) /C ANODE (20 WT.%) WERE PREPARED BY THE BOROHYDRIDE REDUCTION METHOD. BRIEFLY: CARBON BLACK POWDER (VULCAN XC-72, CABOT INC.) WAS USED AS A SUPPORT FOR THE CATALYST, H2PTCL6·6H2O (MERCK, 99.99%) AND NICL2 (MERCK, 99.99%) WERE USED AS PRECURSORS. THE CARBON BLACK WAS ULTRASONICALLY DISPERSED IN A SOLUTION OF ULTRAPURE WATER AND ISOPROPYL ALCOHOL FOR 2 H. THE PRECURSORS WERE ADDED TO THE INK AND THEN MIXED THOROUGHLY FOR ANOTHER 2 H. THE PH VALUE OF THE INK WAS ADJUSTED BY A NAOH SOLUTION TO 9 AND THEN RAISED THE TEMPERATURE TO 80OC. A SOLUTION OF 0.1 MOL L-1 NABH4 WAS ADDED DROPWISE INTO THE MIXTURES, AND THE BATH WAS STIRRED FOR 3 H. THE CATALYST POWDERS WERE DRIED IN A VACUUM OVEN FOR 3 H AT 80◦C AND STORED IN A VACUUM VESSEL. TO OBTAIN A UNIFORM HIGH PURITY FILM, NAFIONÒ 117 WERE CLEANED WITH A STANDARD TREATMENT PROCEDURE WAS ADDRESED IN REF [7].PREPARED NI-PT/C AND NI/C POWDER WERE MIXED WITH 5% NAFIONSOLOUTION, WATER AND ISOPROPYL ALCOHOL SEPARATELY TO FORM CATALYST INK.THIS INK BRUSHED ON CARBON CLOTH WITH GAS DIFFUSION LAYER (GDL). THE LOADING OF GDL ON CARBON CLOTH WAS 2 MG.CM-2 AND THE LOADING OF CATHODE (NI/C) CATALYST INK WAS 0.5 MG.CM-2 BUT THE LOADING OF ANODE CATALYST INK (PT-NI/C) WAS 1 MG.CM-2. FINALLY ANODE, CATHODE AND PRE-TREATED NAFION ® 117 MEMBRANE WERE SANDWICHED TOGETHER AND HOT PRESSED. THE EFFECTIVE GEOMETRICAL AREA OF THE ANODE AND CATHODE WAS 5 CM2…