Interactions and Binding Energies of Dimethyl Methylphosphonate and Dimethyl Chlorophosphate with Amorphous Silica

Abstract

The fundamental interactions of dimethyl methylphosphonate (DMMP) and dimethyl chlorophosphate (DMCP) on amorphous silica nanoparticles have been investigated with transmission infrared spectroscopy and temperature-programmed desorption (TPD). DMMP and DMCP both adsorb molecularly to silica through the formation of hydrogen bonds between isolated silanols and the phosphoryl oxygen of the adsorbate. The magnitude of the shift of the ν(OH) mode upon simulant adsorption is correlated to the adsorption strength. The activation energies for desorption for a single DMMP or DMCP molecule from amorphous silica varied with coverage. In the limit of zero coverage, after the effects of defects were excluded, the activation energies were 54.5 ± 0.3 and 48.4 ± 1.0 kJ/mol for DMMP and DMCP, respectively.

Copper Hydroxyl Nitrate/Graphite Oxide Composite as Superoxidant for the Decomposition/Mineralization of Organophosphate‐Based Chemical Warfare Agent Surrogate

“…Simultaneously, most of the signals related to NO 3 − and OH − groups disappeared. These new bands correspond to the vibration modes of adsorbed DMCP . The most intense band located at 1053 cm −1 is not related to DMCP and it is linked to vibrations of Cu 2 (PO) 4 .…”

“…After 14 h, a band at 1186 cm −1 becomes visible. This band is attributed to ρ (CH 3 O) of the DMCP molecule . After 44 h, a small shoulder band at 1062 cm −1 appears, which is linked either to the symmetric stretching of CO or to the antisymmetric vibration mode of the phosphate–copper complexes .…”

“…An increase in the weight is due to the adsorbed DMCP molecules and/or due to adsorbed surface reaction products. It has been reported that DMCP has the ability to coordinate with silanol groups by hydrogen bonding. It is likely that in our materials hydrogen bonds occur between the hydroxyl terminal groups and the phosphoryl oxygen of DMCP.…”

Multidisciplinary Role of Mesoporous Silica Nanoparticles in Brain Regeneration and Cancers: From Crossing the Blood–Brain Barrier to Treatment

“…In the year 2012, Wilmsmeyer et al, showed that common stimulant, an organophosphorus compound, namely DMMP (dimethyl methylphophonate) binded hydrophilic silica more significantly than DMCP (dimethyl chlorophosphate), indicating that the sarin phosphorus‐halogen bond affects the surface chemistry of the agent in a complicated way . Then in the year 2014, Davis et al studied the energetics and mechanisms that regulated the hydrogen‐bonding interactions when soman and sarin adsorb on silica .…”

Positive Effects of Impregnation of Fe-oxide in Mesoporous Al-Oxides on the Decontamination of Dimethyl Methylphosphonate

“…The adsorption and decomposition of gaseous DMMP molecules on various metal oxides, such as SiO 2 , Al 2 O 3 , MgO, La 2 O 3 , and Fe 2 O 3 , have been investigated by numerous research groups [4,[8][9][10][11][12][13]. Besides, the mixed structure of different metal oxides (or supported metal oxides) and nano-sized metal oxides have been also examined for the decontamination of DMMP molecules [14][15][16][17][18][19], and, recently, the utilization of photo-catalysts has been also suggested [20,21].…”