Designing Fe(II)NNN Pincer Complexes for Base-Free Hydrogen Production from Methanol

Methanol dehydrogenation using earth-abundant catalysts in the absence of any additives presents a promising route for green hydrogen production in fuel cell applications. This study investigates the catalytic performance of three Fe(II)NNN pincer complexes through density functional theory calculations. The turnover frequency analysis, based on the computed free energy activation barriers, reveals that the 1c Fe(II)NNN pincer complex exhibits better catalytic activity in comparison to 1a and 1b Fe(II)NNN pincer complexes. These trends are consistent with electronic structure analyses, including condensed Fukui functions, HOMO-LUMO gap evaluations, and distortion-interaction analysis, which collectively provide insights into the key electronic and structural features enhancing the catalytic performance. Notably, the study indicates that the reaction pathway remains energetically accessible in the absence of an external base, which has great implications for designing base-free catalytic systems. Overall, this study offers critical structure–activity relationship, paving the way for the rational design of next-generation, sustainable catalysts for green hydrogen production from methanol.