Saponite has been widely used in a number of industrial fields because of the higher surface acidity and thermal stability when compared with other clay minerals (Alexander and Dubois, 2000; Casagrande et al., 2005). ...Saponite has been widely used in a number of industrial fields because of the higher surface acidity and thermal stability when compared with other clay minerals (Alexander and Dubois, 2000; Casagrande et al., 2005). Due to its limited natural resource, synthesis of saponite has attracted much attention during the last two decades (Vogels et al., 2005; Bisio et al., 2008). The main aim of this study is to investigate occupancy of Al ions and its effect on the structure of synthetic saponites.展开更多
Synthetic saponites have been intercalated with hydroxyl aluminium oligomers and characterized with several techniques. The basal 001 peak of the pillared saponite (PS) is 1. 8 nm. The amount of the aluminium in the t...Synthetic saponites have been intercalated with hydroxyl aluminium oligomers and characterized with several techniques. The basal 001 peak of the pillared saponite (PS) is 1. 8 nm. The amount of the aluminium in the tctrahedral sheet is correlative with cross-linking density. The sheet-to-pillar linkage mode may be Si-O-AlpⅥ. The acid sites in pillared saponite may locate either at surface of clay or at that of pillar. The cumene conversion is relative to accessible acid sites on the surface of PS. The pillar density in the PS has an effect on the pore structure which is correlative with shape selectivity during the reaction between ethanol and ammonia.展开更多
A kind of layered Li;MSiO;material,Fe saponite with Na;pillaring (Na^(+)-FSAP) was developed as a lowcost and environment-friendly lithium-ion storage material.The Na^(+)-FSAP follows the insertion/deinsertion working...A kind of layered Li;MSiO;material,Fe saponite with Na;pillaring (Na^(+)-FSAP) was developed as a lowcost and environment-friendly lithium-ion storage material.The Na^(+)-FSAP follows the insertion/deinsertion working mechanism accompanied by valence change of Fe from Fe^(1.86+) to Fe^(2.71+) (average value) after stabilization,and displays a specific capacity of 125 m Ah g^(-1) at 50 m A g^(-1) with retention ratio of 80.8%after 75 cycles.The Na^(+)-pillaring effect and abundant structural water in the gallery urge Li^(+) migrate rapidly,resulting in a large Li^(+) diffusion coefficient within a range of 10^(-6.5)–10^(-7.5) cm^(2)s^(-1).Thus,the Na^(+)-FSAP provides a model material to design electrode materials with rapid lithium-ion migration and has great potential to take place of polyanionic-type Li_(2)MSiO_(4)(M=Mn,Fe,Co) cathode materials.展开更多
文摘Saponite has been widely used in a number of industrial fields because of the higher surface acidity and thermal stability when compared with other clay minerals (Alexander and Dubois, 2000; Casagrande et al., 2005). Due to its limited natural resource, synthesis of saponite has attracted much attention during the last two decades (Vogels et al., 2005; Bisio et al., 2008). The main aim of this study is to investigate occupancy of Al ions and its effect on the structure of synthetic saponites.
文摘Synthetic saponites have been intercalated with hydroxyl aluminium oligomers and characterized with several techniques. The basal 001 peak of the pillared saponite (PS) is 1. 8 nm. The amount of the aluminium in the tctrahedral sheet is correlative with cross-linking density. The sheet-to-pillar linkage mode may be Si-O-AlpⅥ. The acid sites in pillared saponite may locate either at surface of clay or at that of pillar. The cumene conversion is relative to accessible acid sites on the surface of PS. The pillar density in the PS has an effect on the pore structure which is correlative with shape selectivity during the reaction between ethanol and ammonia.
基金supported by the National Natural Science Foundation of China(21671015 and U1707603)the Fundamental Research Funds for the Central Universities(XK1802-6,BHYC1702B,and XK1803-05)the Beijing Municipal Science&Technology Commission(Z191100002019013)。
文摘A kind of layered Li;MSiO;material,Fe saponite with Na;pillaring (Na^(+)-FSAP) was developed as a lowcost and environment-friendly lithium-ion storage material.The Na^(+)-FSAP follows the insertion/deinsertion working mechanism accompanied by valence change of Fe from Fe^(1.86+) to Fe^(2.71+) (average value) after stabilization,and displays a specific capacity of 125 m Ah g^(-1) at 50 m A g^(-1) with retention ratio of 80.8%after 75 cycles.The Na^(+)-pillaring effect and abundant structural water in the gallery urge Li^(+) migrate rapidly,resulting in a large Li^(+) diffusion coefficient within a range of 10^(-6.5)–10^(-7.5) cm^(2)s^(-1).Thus,the Na^(+)-FSAP provides a model material to design electrode materials with rapid lithium-ion migration and has great potential to take place of polyanionic-type Li_(2)MSiO_(4)(M=Mn,Fe,Co) cathode materials.
