STUDY OF TYPE OF ELECTROLYTE EFFECT ON PLATINUM ELECTRO-CATALYST PERFORMANCE PREPARED BY CYCLIC VOLTAMMETRY ELECTRODEPOSITION METHOD FOR GLUCOSE OXIDATION REACTION

There are several methods to prepare electro-catalysts for low temperature fuel cells. Platinum is used as a common electro-catalyst for this purpose. Electrodeposition method is applied for preparing platinum on modified carbon paper as electrode directly. Many parameters effect on performance of prepared electrodes. At this work, the effect of type of electrolyte in electrodeposition solution was investigated for making electro-catalyst that is be used as anode in Glucose Alkaline Air Fuel Cell (GAAFC). Cyclic voltammetry ((1.2-0.6) V vs. Ag/AgCl sat. KCl, 100 mV/S) is used as electrodeposition method. Number of CV cycles is varied 10 to 50. Electrodeposition was performed in two precursor solution (0.5 M) containing phosphate and sulfate anions. Platinum concentration in solution was 3 mM. The prepared electro-catalysts were studied for Glucose Oxidation Reaction (GOR) by CV analysis in 0.3 M glucose solution and 0.5 M KOH. Also, Electrochemical Impedance Spectroscopy (EIS) method was used. According our results, the type of anion in electrodeposition solution affects on properties of prepared platinum electro-catalyst for GOR. Optimized condition for number of CV cycles in phosphate and sulfate solutions is 10 and 40 respectively.&nbsp

The Effectiveness of Science, Technology, Engineering, and Mathematics based Education in Solar Energy Context on Attitude and Academic Achievement of Female Students

The integrated approach of science, technology, engineering and mathematics (STEM) has been introduced in order to create a new development in the effective teaching of science and its relationship with daily life in recent years. The present study was designed to investigate the effect of this approach on attitudes and academic achievement. The study population consisted of ninth grade female secondary school students in Qarchak city in the academic year 2020-2021 and the convenience sampling consisted of 143 people who were selected by random sampling in two groups of control and experimental. The Students in the experimental group were educated in solar energy for 7 sessions (each session: 35 minutes) with a STEM based approach. Covariance analysis and independent t-test showed that teaching science with the STEM based approach increased students' attitude in STEM and had a significant effect on their learning in science. Also, according to Pearson correlation test, there is a significant correlation between attitudes in STEM and academic achievement

The effect of reaction layer composition on Pt/NiO function for glucose oxidation reaction in neutral media

This study shows the application of carbon supported electrodes containing Pt/NiO nanoparticles to catalyze the electrochemical oxidation of glucose in neutral media. In particular, this study describes the effect of the Pt content and type of carbon (carbon black, expanded graphite, or charcoal active) in the reaction layer on this oxidation process in neutral media. Pt/NiO nanoparticles were synthesized by a simple hydrothermal method, and further characterized by scanning electron microscopy (SEM), X-ray diffraction spectroscopy (XRD), and cyclic voltammetry. These nanoparticles were used to modify carbon electrodes. The effectiveness of these electrodes for electrochemical glucose oxidation was evaluated. The results revealed that the catalytic activity of the electrodes depends on the content of Pt/NiO nanoparticles and the type of carbon. The 10% Pt/NiO with 90% loading (use of activated charcoal in the reaction layer) as optimum electrode indicated good stability after 1200 voltammetry cycles. This modified electrode was highly active for glucose oxidation in neutral media, which could be attributed to the presence of Pt/NiO nanoparticles as catalyst and high surface area of activated charcoal on the electrode surface