Designing Innovative Bimetallic and Trimetallic Complexes Inspired by Metalloenzymes for Hydrogen Activation and Molecular Electronics
Metalloenzymes like [NiFe] and [FeFe] hydrogenases exemplify nature’s proficiency in hydrogen activation through multi-metallic assemblies and dynamic ligand environments that facilitate proton-coupled electron transfer (PCET). Drawing inspiration from these enzymatic systems, our research focuses on designing bimetallic and trimetallic complexes that mimic these functionalities for hydrogen-based energy conversion and molecular electronics.
A key aspect of our design involves employing hemilabile metallodithiolate ligands, which stabilize metal centers while offering additional coordination sites for further metalation. These ligands exhibit adaptive coordination behavior, promoting reversible ligand binding upon protonation to modulate electronic properties and facilitate catalytic intermediates. Additionally, redox-active and proton-responsive ligands enhance metal-ligand cooperativity, central to efficient hydrogen activation.
To probe the electronic structures, catalytic mechanisms, and redox behaviors of these complexes, we utilize a combination of electrochemical and spectroscopic techniques. Cyclic voltammetry (CV) is employed to evaluate redox properties and catalytic efficiency, while spectro-electrochemistry provides insights into oxidation state transitions. Techniques such as electron paramagnetic resonance (EPR), infrared (IR), and UV-Vis-NIR spectroscopy further elucidate electronic and structural changes during catalysis. Magnetic susceptibility measurements offer additional perspectives on spin-state dynamics.
Beyond catalysis, this project explores the potential of these complexes as molecular memristors, leveraging their ability to access multiple redox states and exhibit tunable conduction properties. By capitalizing on counterion activity, charge delocalization, and ligand-based redox switching, we aim to establish structure-function relationships that facilitate controlled resistive switching. These findings contribute to the advancement of both sustainable hydrogen technologies and next-generation memory storage materials.
Our research bridges the gap between biological and synthetic models, offering a dual approach to addressing challenges in clean energy and molecular electronics. By uniting bioinspired catalysis with molecular memory applications, we provide insights into the design of multifunctional materials with transformative potential.