Sustainable Heterogeneous Chlorination with Organic Molecule-Modified Single-Atom Electrocatalysts

The conventional synthesis of organochlorides, vital building blocks in agrochemical and pharmaceutical industries, predominantly relies on thermochemical methods that operate with noble-metal organic ligands and generate stoichiometric hazardous waste, posing significant environmental and economic challenges. Electrocatalysis presents a sustainable alternative by using electricity as a clean and tunable reagent, enabling reactions under mild conditions with reduced ecological footprint. While single-atomcatalysts (SACs) offer maximal atom efficiency and unique electronic properties, their practical application in anodic chlorination is severely limited by metal leaching and structural degradation under highly oxidizing potentials, which curtails their long-term usability and industrial relevance. This project aims to develop a novel strategy to stabilize SACs by engineering their coordination microenvironment through covalent modification with tailored organic molecules, forming a class of materials we term organocatalyst supported on single-atom supports (OSASs). We hypothesize that grafting functional organic ligands onto the SAC support will enhance metal anchoring via strong coordination bonds and modify the local electronic structure, thereby promoting charge transfer and reactant activation, leading to superior catalytic stability and activity.The key objectives of this project are: 1) To design and synthesize a library of nitrogen-based organic molecules with tailored electronic and steric properties for modifying carbon-supported non-noble metal based SACs; 2) To systematically characterize the physicochemical properties of the hybrid catalysts using advanced techniques such as Xray absorption spectroscopy and scanning transmission electron microscopy to unravel the structure-modification relationship; 3) To evaluate the electrocatalytic performance towards chlorination of aromatic compounds and the production of key drug intermediates, with a focus on benchmarking stability against metal leaching and assessing Faraday efficiency and selectivity under continuous operation conditions; 4) To realize the kg-scale synthesis of the key drug molecules, demonstrating scalability and potential for industrial adoption.Till now, we have primarily demonstrated that the SACs and OSASs are efficient in the inorganic chlor-related reactions. The ultimate goal is to demonstrate a proof-of-concept for a new class of robust organic-inorganic hybrid electrocatalysts that combine the advantages of molecular precision and heterogeneous stability. The expected outcome is a stable catalytic system that maintains high performance over extended operation, providing a generalizable platform for applying SACs in other challenging electrocatalytic organic reactions. This research will provide fundamental insights into stabilizing metal sites through molecular-level engineering, advancing the frontier of sustainable electrochemical synthesis for fine chemicals and bridging the gap between academic innovation and industrial application.