Design of N-(benzothiazol-2-yl)benzamide-Pd complexes with amine and diphosphine co-ligands to enhance hydrogen storage: increasing structural diversity while maintaining uniqueness
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Faisal A. Salman
Abstract
This study entails the synthesis and characterization of palladium complexes containing N-(benzothiazol-2-yl)benzamide (LH) along with various hybrid ligands, including 2-aminopyridine (2amp), 4-aminopyridine (4amp), phenanthroline (Phen), triphenylphosphine (PPh3), as well as diphosphines such as dppp and dppb. Characterization of the prepared complexes was performed using molar conductivity analyses, FTIR, 31P-NMR, 1H-NMR, and 13C-NMR spectra. The proposed geometry around the metal ion is mostly planar, with the LH bond acting as a bidentate bond via the N atom of the pentameric ring in the benzothiazole and the O atom of the carbonyl group. The hydrogen storage capacities of selected complexes were evaluated under high pressure using the VTI/HPVA method. The results indicate that all complexes studied exhibit hydrogen storage capacity, with the highest storage values observed in [Pd(LH)(4amp)2]Cl2, [Pd(LH)(dppb)]Cl2, and [Pd(LH)(PPh3)Cl]Cl complexes reach 471, 212, 166 mL g−1, respectively.
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Research ethics: Not applicable.
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Informed consent: Not applicable.
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Author contributions: All authors have accepted responsibility for the entire content of this manuscript and approved its submission.
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Use of Large Language Models, AI and Machine Learning Tools: None declared.
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Conflict of interest: The authors state no conflict of interest.
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Research funding: Not applicable.
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Data availability: Data will be available on request.
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Supplementary Material
This article contains supplementary material (https://doi.org/10.1515/ijmr-2024-0112).
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