[Sn₂S₆]^4– Anion-Intercalated Layered Double Hydroxides for Highly Efficient Capture of Iodine

Abstract

The development of low-cost and high-efficiency iodine sorbents is of great significance for the control of nuclear pollution. In this work, we intercalate the tin sulfide cluster of [Sn2S6]4– to Mg/Al-type layered double hydroxides to obtain Sn2S6-LDH, which exhibits highly efficient capture performance of iodine vapor and iodine in solutions. The dispersion effect of the positively charged LDH layers contributes to the adequate exposure of [Sn2S6]4– anions, providing plentiful adsorption sites. For iodine vapor, Sn2S6-LDH showed an extremely large iodine capture capacity of 2954 mg/g with a large contribution from physisorption. For iodine in solutions, a significantly large sorption capacity of 1308 mg/g was achieved. During iodine capture, I2 molecules were reduced to I– ions (by S2– in [Sn2S6]4–), which then reacted with Sn4+ to form SnI4, where the molar amount of captured iodine is 4-fold that of Sn. Besides, the as-reduced I– combined with I2 again to generate [I3]−, which then entered the LDH interlayers to maintain electric neutrality. While reducing iodine, S2– itself in [Sn2S6]4– was oxidized to S8, which further combined with SnI4 to form a novel compound of SnI4(S8)2. The excellent iodine capture capability endows Sn2S6-LDH with a promising application in trapping radioactive iodine.

Supramolecular Structure of the β-Cyclodextrin Metal–Organic Framework Optimizes Iodine Stability and Its Co-delivery with l-Menthol for Antibacterial Applications

“…Therefore, it is always prohibited to measure pure iodine for SEM and XPS tests to prevent equipment contamination. However, I 2 complexed in compounds such as polyiodides could be analyzed using SEM and XPS as sublimation is no longer a concern. − For the carrier β-CD-POF(I) used in this study, I – was coordinated with β-CD to form a framework. I 2 was stably encapsulated within the cavities of β-CD-POF(I) and did not readily vaporize even under high vacuum, enabling accurate characterization via SEM and XPS.…”

Hollow Bismuth-Based Nanoreactor with Ultrathin Disordered Mesoporous Silica Shell for Superior Radioactive Iodine Decontamination

“…The development of metal-modified sorption materials is a viable solution, utilizing their chemical reactions with I 2 to generate corresponding metal iodides and achieve the removal of radioactive iodine. − Various metals, such as Ag, − Cu, , Sn, , and Bi, − and their oxides have been investigated for this purpose. Among them, silver-based materials (SBMs) have undergone the most comprehensive fundamental research and are currently the most widely applied iodine sorption materials in the nuclear industry. , Relevant experimental results demonstrate that SBMs can selectively remove radioactive iodine under the high-temperature conditions typical of real-world operations, making them reliable iodine sorption materials in practical applications.…”