Zinc oxide (ZnO) nanoparticles were used as the photocatalyst to develop self-decontaminating fibers for potential use as chemical protective materials. Since ZnO is an effective photocatalyst for degradation of organophosphate, it was incorporated in electrospun polyacrylonitrile (PAN) fibers. Photocatalytic degradation of methyl parathion, an organophosphate, upon exposure to ZnO-PAN fibers was evaluated and found to be effective for reuse for up to five exposure cycles. High performance liquid chromatography, UV-vis spectroscopy, calculations of octanol-water partition coefficients, and P-31 NMR spectroscopy were used to determine that hydrolysis is the probably mechanism for photocatalytic degradation.