Bahdişen GEZER, Başak URHAN, Yusuf ERSOY
Abstract: Introduction: Energy is known to be the most important consumption material of our age and it causes increasing energy demand due to increasing population, urbanization, industrialization day by day. This makes energy more important. A large majority of the energy currently used is from fossil fuels such as coal, oil, and natural gas. But the environmental problems such as global warming and air pollution caused by these fossil fuels, as well as the fact that these resources will be exhausted one day, have led people to search for new energy sources. For this reason, many alternative energy sources such as wind energy, solar energy, fuel cells have come to the forefront as renewable energy sources for clean energy. Fuel cells are seen as the right choice to get electricity with their distinctive features such as being more efficient and making less noise. But the biggest disadvantage of fuel-packed batteries is the price problem, because electrochemical cells are reliable, great efforts are being made to solve this problem. The majority of fuel pellets are used as hydrogen and alcohol fuel. For this reason, work continues on the use of fuel cells in vehicles and other portable electronic devices. Direct methanol fuel cells (DMYP) have become a major concern in recent years due to potential applications in electric vehicles and portable power sources. Methanol is a liquid suitable for electro-oxidation in direct fuel cells. As an alternative to this fuel, ethanol is a promising fuel that can easily be produced by non-toxic sugar-containing raw materials and agricultural products. In addition, the high theoretical mass has a high energy density and therefore it has a very high potential to be used as fuel. Goal: Recently, Pt-based nanocatalysts have been prepared and used to activate these alcohols. Pt is a good catalyst for the synthesis of small organic molecules. It is being modified to improve fuel cell performance and durability. For this purpose, Co-stabilized Pt (0), Pt (II) and Pt (IV) nanoparticles were synthesized as direct surfactant by direct sonication. Scope: In our work we focused on Pt-Co alloys based on the results of previous work-ups obtained with a Pt (X) Co alloy in terms of activity and stability. Pt-Co alloys were synthesized and characterized by a Pt surface enriched by physicochemical characterization and an alloyed PtCo core. All electrocatalysts have been tested to evaluate the behavior of these electrodes under more practical conditions in a half cell configuration for oxygen reduction reactions (ORR) and a direct methanol fuel cell (DMFC) catheter. In particular, studies have been conducted focusing on the use of high methanol concentrations for high energy density systems based on DMFC, which exhibit promising performance and durability characteristics related to the synergistic effects of Pt-Co alloys. Method: Pt and Co nanocatalysts were synthesized directly by sonication. Briefly, a mixture was obtained by adding 0.25 mmol of CoCl4 to 0.25 mmol of PtCl4 matal complex dissolved in a small amount of tetrahydrofuran solution. An appropriate amount of support was ultrasonically dispersed in water for 1 h and then mixed with the Pd-sulphite acidic solution. Subsequently, H2O2was added to decompose the sulfite complex with the formation of a colloidal suspension (Pt-Co) after pH correction (5.5). Hence, the suspension was filtered, copiously washed with water and dried at 80 °C, overnight. Discussion: The prepared catalyst analyzed with the help of techniques such as X-ray diffraction (XRD), Transmission Electron Microscopy (TEM), High Resolution Transmission Electron Microscopy (HRTEM), X-ray Photoelectron Spectroscopy (XPS) and Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES ). Result: According to the results obtained in the study, it was observed that the Pt-Co nanocatalyst was tested at room temperature reactions and exhibited high catalytic activity. This is explained by the roughness factor being the high% Pt content and the highly monodispersed Co surface of the prepared nanoparticles. It has also been found that the structure and size of the surface active material has an effect on the catalytic activity of the metal nanoparticles. It has been determined that the Pt-Co catalyst is related to having a branched structure with a high particle size. In addition, more branched surfactants tend to form larger micelle openings, which leads to the growth of the crystal particle size in XRD and to the observation of an increase in metal particle size in TEM.

Anahtar Kelimeler: Alcohol fuel cell, catalyst, platinum cobalt based catalyst, sonication