Dual-Functional Hydrogen-Bonded Organic Frameworks for the Detoxification and Capture of a Mustard Gas Simulant

Sulfur mustard, a highly toxic organosulfur-based chemical warfare agent (CWA), poses significant risks to both human health and the environment. While metal-organic frameworks (MOFs) have been widely explored for capturing and degrading CWA, hydrogen-bonded organic frameworks (HOFs) remain underexplored, despite their permanent porosity, water stability, and ease of synthesis. In this study, we demonstrate the photocatalytic oxidation of the sulfur mustard simulant 2-chloroethyl ethyl sulfide (CEES) using two distinct HOFs. The first, HOF-111, is a framework presented for the first time, synthesized from 2,3,6,7,10,11-hexakis(4-carboxyphenyl)triphenylene (HCPT) and achieves efficient CEES degradation under UV light irradiation. To extend the catalytic activity into the visible region, we synthesized the phenazine-based CPHATN-HOF, derived from hexaazatrinaphthylene (CPHATN), which features increased π-conjugation relative to HOF-111, thereby red-shifting absorption and enabling effective photocatalysis under both visible light and sunlight. In addition, CEES microbreakthrough studies reveal that HOF-111 exhibits identical kinetic uptake capacities for CEES vapor under both dry and humid conditions, likely due to its hydrophobic pore environment and inherent porosity. Collectively, this work establishes HOFs as promising dual-functional protective materials capable of capturing and detoxifying CEES under ambient conditions.