Development of a Metal–Organic Framework/Textile Composite for the Rapid Degradation and Sensitive Detection of the Nerve Agent VX

In the case of an incident with nerve agents, the timely and ready detection and identification of such a substance on suspected surfaces is essential. However, the detection of low levels of nerve agents on a surface is a considerable challenge for conventional detection equipment, especially with VX, a highly toxic nerve agent with low volatility. Here, we report the development of a metal–organic framework (MOF)/fabric composite that gives a rapid, visual, and sensitive color response when pre-wetted and rubbed over a VX-contaminated surface. The fabric is composed of cotton textile modified with the zirconium-based MOF MOF-808 that possesses a bidentate reactive dye, ditopic 5,5-dithiobis(2-nitrobenzoic acid) (DTNB), on its nodes. The crystal structure of DTNB@MOF-808 showed that DTNB bridges between two adjacent nodes in MOF-808. The colorless composite changes to bright orange upon contact with VX as a result of the degradation of VX and the concomitant reaction of the dye with a VX degradation product in the MOF pores.