Synergistic effect of Lewis acid-base sites in Zr4+-doped layered double hydroxides promotes rapid decontamination of nerve and blister agents under ambient conditions

Abstract

Nerve and blister agents are among the deadliest chemicals posing a major threat to the society, and the development of materials that can rapidly decontaminate them under solvent-free ambient conditions is a major societal challenge. In this paper, layered double hydroxides (ZnAl_xZr_1-x-LDH) with varying Zr⁴⁺ doping content were synthesized and the decontamination properties of nerve and blister agents were investigated under ambient conditions. The results show that, compared to ZnAl-LDH, the ZnAl_0.4Zr_0.6-LDH with the highest amount of Zr⁴⁺ dopant reduced the decontamination reaction half-life of sarin (GB) and soman (GD) by 10 and 9 times, respectively. Mechanism studies revealed that ZnAl_0.4Zr_0.6-LDH employs the synergistic effect of Lewis acid-base sites to catalyze the decomposition of GB and GD into hydrolysis products and surface-bound hydrolysis products. The study also showed that under ambient conditions, ZnAl_0.4Zr_0.6-LDH demonstrated superior decontamination performance for the sulfur mustard (HD) simulant 2-chloroethyl ethyl sulfide (CEES) compared to ZnAl-LDH, effectively catalyzing the detoxification of CEES into dehydrohalogenation (EVS) and 1,2-bis-(ethylthio) ethane (BETE). ZnAl_0.4Zr_0.6-LDH also had satisfactory decontamination performance against HD. This work provides not only a green and efficient catalyst with potential for practical applications but also new insights for constructing broad-spectrum, highly efficient self-detoxifying materials.