Photo-decontamination of chemical warfare dimethyl methylphosphonate, dimethyl phosphite, diethyl methylphosphonate, diethyl phosphite model molecules on Al and oxidized Al foils

[Display omitted] •A dry UV light photo-decontamination method for chemical warfare agents (CWAs) was demonstrated.•Decomposition of DMMP, DMP, DEMP, and DEP, and roles of PH, PCH3, OCH3, and OCH2CH3 groups were examined.•Density functional theory for geometry optimization and the electronic energy state calculation.•Gas products by GC–MS, and solid residues by XPS and FT-IR were examined with reaction pathways.•MeOH and EtOH were major products boosted by photoirradiation. Decontamination of organophosphorus chemical warfare nerve agents (CWNAs) is gaining importance for human security. Herein, we have employed a dry-photodecontamination method for CWNA model molecules of dimethyl methylphosphonate, dimethyl phosphite, diethyl methylphosphonate, and diethyl phosphite contaminated on aluminum (Al) and oxidized Al foils. For understanding their photo-degradation pathways, the photo-decomposition secondary chemical products generated as a result of UVC-decontamination were fully examined for the contaminated Al and oxidized Al target areas in a closed reactor system by gas chromatography and mass spectrometry. Solid residues were also fully examined by X-ray photoelectron spectroscopy and Fourier-transform infrared spectroscopy. Density functional theory at the B3LYP/6–31 G level was used for geometric optimization, and the electronic energy state calculation was conducted on the level of TD-SCF/B3LYP/6–31 G. The new results further deepen the photo-decomposition mechanism of CWNAs, the development of dry UV light photo-decontamination methods, and the treatment of secondary by-products.