Multiscale structural control of thiostannate chalcogels with two-dimensional crystalline constituents

oleh: Thanh Duy Cam Ha, Heehyeon Lee, Yeo Kyung Kang, Kyunghan Ahn, Hyeong Min Jin, In Chung, Byungman Kang, Youngtak Oh, Myung-Gil Kim

Format: Article
Diterbitkan: Nature Portfolio 2022-12-01

Deskripsi

Abstract Chalcogenide aerogels (chalcogels) are amorphous structures widely known for their lack of localized structural control. This study, however, demonstrates a precise multiscale structural control through a thiostannate motif ([Sn2S6]4āˆ’)-transformation-induced self-assembly, yielding Na-Mn-Sn-S, Na-Mg-Sn-S, and Na-Sn(II)-Sn(IV)-S aerogels. The aerogels exhibited [Sn2S6]4āˆ’:Mn2+ stoichiometric-variation-induced-control of average specific surface areas (95–226 m2 gāˆ’1), thiostannate coordination networks (octahedral to tetrahedral), phase crystallinity (crystalline to amorphous), and hierarchical porous structures (micropore-intensive to mixed-pore state). In addition, these chalcogels successfully adopted the structural motifs and ion-exchange principles of two-dimensional layered metal sulfides (K2x Mn x Sn3-x S6, KMS-1), featuring a layer-by-layer stacking structure and effective radionuclide (Cs+, Sr2+)-control functionality. The thiostannate cluster-based gelation principle can be extended to afford Na-Mg-Sn-S and Na-Sn(II)-Sn(IV)-S chalcogels with the same structural features as the Na-Mn-Sn-S chalcogels (NMSCs). The study of NMSCs and their chalcogel family proves that the self-assembly principle of two-dimensional chalcogenide clusters can be used to design unique chalcogels with unprecedented structural hierarchy.