A Light-Responsive Metal–Organic Framework with Perchlorinated Nanographene Ligands
Xin Zheng, Nikita Gupta, Haiying He, Jasleen K. Bindra, Subharaj Hossain, Juan P. Vizuet, Atefeh Nadeali, Danial Zangeneh, Roushan Prakash Singh, Robert F. Klie, Brian P. Chaplin, Kenneth Brezinsky, Oleg G. Poluektov, Jens Niklas, Peter Zapol, Ksenija D. Glusac
Abstract
Harnessing water as a sustainable electron source for artificial photosynthesis remains a significant challenge. This work presents Alice-MOF-1, a novel zirconium metal–organic framework (MOF) incorporating hexatopic ligands with a perchlorinated hexa- peri -hexabenzocoronene (HBC) core, as a photocatalyst for CO 2 reduction using water as the terminal electron donor. Contortion of the ligand, induced by edge chlorination, minimizes π-stacking and enhances solubility, enabling direct MOF synthesis. The controlled arrangement of chromophores within Alice-MOF-1 is crucial for enabling the complex multielectron redox reactions. The unique ligand architecture within the MOF promotes symmetry-breaking charge transfer (SBCT), a mechanism observed in natural photosynthesis, leading to efficient charge separation with minimal energy loss. Femtosecond transient absorption spectroscopy and time-resolved electron paramagnetic resonance spectroscopy (EPR) confirm the formation of long-lived radical ions, providing direct evidence for efficient SBCT and negligible charge recombination. These findings demonstrate the power of MOF-based chromophore assemblies to mimic nature’s light-harvesting strategies for sustainable energy conversion.