Synthesis of new generation alkyne derivatives and hydrogen production applications

Thymol molecule isolated from natural sources and pyrrole molecule containing heteroatoms are organic compounds that attract attention with their biological activities as well as their potential in the field of energy. In this study, graphene oxide (GO) composites were prepared with synthesized new organic structures and their catalytic efficiency in hydrogen production via sodium borohydride (NaBH₄) methanolysis was investigated. Structures of 2-(3-(2-isopropyl-5-methylphenoxy)prop-1-in-1-yl)aniline (o-IMPA), 4-(1Hpyrrol- 1-yl)aniline (PYRA) and 4-(3-(2-isopropyl-5-methylphenoxy)prop-1-yn-1-yl)aniline (p-IMPA) were synthesized using Sonogashira Docking reaction, Ullmann type N-arylation reaction and Nucleophilic substitution reactions. Graphene oxide was synthesized by Modified Hummers method. Organic molecules and GO were modified in different ratios using the Steglich esterification reaction. The obtained catalysts were characterized by XRD, Raman, FTIR, SEM-EDX and DFT calculations. The hydrogen production performances of the obtained composite catalysts were tested by NaBH₄ methanolysis reaction and optimization studies were carried out for the new generation material with high hydrogen production capacity. In this context, catalyst amount, NaBH₄ amount, methanol volume and temperature parameters were systematically varied and suitable conditions were determined for each catalyst. The hydrogen production rates for o-IMPA/GO, p-IMPA/GO and PYRA/GO composites were determined as 92.017,2 mL/min.gkat, 94.719,6 mL/min.gkat and 121.884,0 mL/min.gkat, respectively. As a result of the kinetic studies, the activation energies of the methanolysis reaction were calculated as 14.55 kJ/mol for o-IMPA/GO, 10.39 kJ/mol for p-IMPA/GO and 30.43 kJ/mol for PYRA/GO using Arrhenius equation.