Battling Chemical Weapons with Zirconium Hydroxide Nanoparticle Sorbent: Impact of Environmental Contaminants on Sarin Sequestration and Decomposition.
Battling Chemical Weapons with Zirconium Hydroxide Nanoparticle Sorbent: Impact of Environmental Contaminants on Sarin Sequestration and Decomposition.
复制标题
用氢氧化锆纳米颗粒吸附剂对抗化学武器：环境污染物对沙林封存和分解的影响。
作者：
Robert B. Balow;M. McEntee;I. Schweigert;Seokmin Jeon;G. Peterson;P. Pehrsson
用常见的环境污染物(CO2、SO2和NO2)对前景看好的活性氢氧化锆(ZH)进行挑战，以确定其对化学战剂分解的影响。几种环境吸附物质通过可利用的羟基物种和配位不饱和的锆位在ZH表面迅速形成。使用包括原位漫反射红外傅里叶变换光谱(DRIFTS)在内的一套仪器来实时监测沙林(GB)在常压下的分解，以确定ZH的去污效果。用非原位X射线光电子能谱(XPS)对表面产物进行了表征。用密度泛函理论(DFT)计算了环境污染物和GB分解产物的吸附热、吸附熵和键长。与XPS和DRIFT结果一致的是，密度泛函模拟预测了分子吸附物和反应产物的相对稳定性顺序为：CO_2<；NO_2<；GB≈SO_2。在ZH上的微穿透容量测量显示，NO2的吸附比SO2的吸附增加了7倍，这表明这些物种的表面反应活性存在差异。在清洁和添加CO2的ZH上，GB分解较快，而在SO2和NO2预添加的样品上，GB的分解速度较慢。尽管有这些发现，干净的和预先给药的ZH在所有样品中的总GB吸附容量是一致的。这些数据提供了对ZH作为反应性吸着剂用于化学去污应用的真实世界的洞察。
The promising reactive sorbent zirconium hydroxide (ZH) was challenged with common environmental contaminants (CO2, SO2, and NO2) to determine the impact on chemical warfare agent decomposition. Several environmental adsorbates rapidly formed on the ZH surface through available hydroxyl species and coordinatively unsaturated zirconium sites. ZH decontamination effectiveness was determined using a suite of instrumentation including in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) to monitor sarin (GB) decomposition in real time and at ambient pressure. Surface products were characterized by ex situ X-ray photoelectron spectroscopy (XPS). The adsorption enthalpies, entropies, and bond lengths for environmental contaminants and GB decomposition products were estimated using density functional theory (DFT). Consistent with the XPS and DRIFTS results, DFT simulations predicted the relative stabilities of molecular adsorbates and reaction products in the following order: CO2 < NO2 < GB ≈ SO2. Microbreakthrough capacity measurements on ZH showed a 7-fold increase in the sorption of NO2 vs SO2, which indicates differences in the surface reactivity of these species. GB decomposition was rapid on clean and CO2-dosed ZH and showed reduced decomposition on SO2- and NO2-predosed samples. Despite these findings, the total GB sorption capacity of clean and predosed ZH was consistent across all samples. These data provide insight into the real-world use of ZH as a reactive sorbent for chemical decontamination applications.