15353

1514دكتري

دكتري

شيمي فيزيك

اصفهان : دانشگاه صنعتي اصفهان

1398

پانزده،116 ص.: مصور، جدول ، نمودار

محمد ژياني

حسين غريبي، علي اصغر انصافي

سهيلا جواديان، كيوان رئيسي، محمد محسن مومني

1398/09/23

كتابنامه

شيمي

شيمي

1398/09/23

2583785

117 Fabrication and evaluation of Ni based nano catalysts on hybrid graphite graphen support for hydrogen evolution reaction in anion exchange membrane electrolyzer Fariba Jalili E mail fariba jalili@ch iut ac ir jalilifariba iut@yahoo com Jun 2019 Department of Chemistry Isfahan University of Technology 84156 83111 Isfahan IranSupervisor Dr Mohammad Zhiani Advisor Dr Hussein Gharibi Prof Ali Asghar Ensafi Department Graduate Coordinator Dr Mohammad dinari Department of Chemistry Isfahan University of Technology Isfahan 84156 83111 Faculty of Basic Science Tarbiat Modares University Tehran 14115 111AbstractIn this thesis Ni BG NiCu BG NiCo BG NiCr BG NiZn BG NiMn BG and NiFe BGelectrocatalysts were prepared and after characterization the composites were employed as thehydrogen evolution reaction HER electrocatalysts in alkaline medium In order to characterize theprepared samples several techniques were employed such as FTIR XRD SEM TEM Raman andEDX analysis In the first section the non platinum electrocatalyst PdNiFeCo C Ceria andcommercial platinum 10 wt Pt C were coated on the nickel foam and activity of them compared tothe bare nickel foam The non platinum electrocatalyst showed a low Tafel slope 79 mV dec 1 andlow overpotential 4 mV in HER Also the performance of electrocatalyst as the cathode electrodewas investigated in an anion exchange membrane AEM electrolyzer In the second section amixture of graphene graphite as support was prepared by ball milling procedure at different times andnano particles of nickel were grown into the mixture graphene graphite substrate The resultsindicated that by raising the time of the ball milling from 0 to 270 min the HER activity ofelectrocatalyst first increased and then decreased according to the increase of active sites and thenagglomeration of Ni nanoparticles Ni nanoparticles supported on the mixture with 180 min ballmilling exhibited the highest HER activity with a low overpotential 118 mV a small Tafel slope 84mV dec 1 The third section was devoted to the preparation of Ni based binary composites withavailable 3d row transition metals Co Fe Mn Cr Cu and Zn on the best mixture of hybridgraphene graphite support with 180 min ball milling The results showed that the Ni Cu alloy Ni Cumol ratio 4 1 had the highest catalytic activity with a low overpotential 100 mV and a small total cm2 due to high catalytically active surface area and intrinsic catalytic activity resistance 167Also the Ni Cu alloy was employed as the cathode in AEM electrolyzer and showed a loss voltage of0 03 V during 50 h operation In the last section composites of Ni and Cu with Ni mol ratio of 0 25 50 75 and 100 are prepared into the hybrid graphene graphite substrate with 180 min ball milling Itwas found that the electrocatalytic activity for the HER depended on the composition of Ni and Cu where Ni25Cu75 alloy exhibited considerably higher HER activity than other composites Theobtained results of this thesis introduce the investigated samples as the promising electrocatalystswhich could be employed in the cathode side of water electrolyzer in alkaline media Keywords graphene graphite Nickel nanoparticles Hydrogen evolution reaction anion exchangemembrane electrolyzer Ni Cu alloy Alkaline Media

محمد ژياني

حسين غريبي، علي اصغر انصافي

سهيلا جواديان، كيوان رئيسي، محمد محسن مومني