Potential Hydrogen Storage Complexes: Short-time Microwave-assisted Synthesis, Characterization, Thermodynamic, and International Relations

This work included preparing and characterizing new platinum complexes with the ligand 3,4,5 -trimethoxybenzoic acid (TMB). The reactions were carried out using a n autoclave in microwave within 3 minutes only in an alkali medium of triethylamine, where two moles of TMB reacted with one mole of platinum ion and two moles of PPh 3, or with one mole of diphosphines (Bis(diphenylphosphino)x; x=methane (dppm), ethane (dppe), propane (dppp), ferrocene (dppf)). The prepared complexes were characterized by measuring melting points and by the techniques of (C.H.N), molar electrical conductivity, FT -IR and 1 H -NMR. The characterization results demonstrated that the TMB ligand behaves as a bidentate ligand through the oxygen atom of the carboxylic groups, and its geometric shape is a square planar around the platinum ion. The complex formed with high yield ([Pt(TMB) 2(dppf)]) was used in hydrogen storage application. The storage isotherm showed that the complex has a high storage capacity of about 4.2 wt% at 61 bar under low temperature (77 K). The study showed that the thermodynamic functions were -0.67KJ/mol and -3.6 J/mol H 2 for enthalpy and entropy, indicating the occurrence of physical hydrogen storage.