Note: When clicking on a Digital Object Identifier (DOI) number, you will be taken to an external site maintained by the publisher.
Some full text articles may not yet be available without a charge during the embargo (administrative interval).
What is a DOI Number?
Some links on this page may take you to non-federal websites. Their policies may differ from this site.
-
We report a synthetic strategy to integrate discrete coordination cages into extended porous materials by decorating opposite charges on the singular cage, which offers multidirectional electrostatic forces among cages and leads to a porous supramolecular ionic solid. The resulting material is non-centrosymmetric and affords a piezoelectric coefficient of 8.19 pC N −1 , higher than that of the wurtzite ZnO.more » « less
-
more » « less
Abstract Synthesizing solids in molten fluxes enables the rapid diffusion of soluble species at temperatures lower than in solid‐state reactions, leading to crystal formation of kinetically stable compounds. In this study, we demonstrate the effectiveness of mixed hydroxide and halide fluxes in synthesizing complex Sr/Ag/Se in mixed LiOH/LiCl. We have accessed a series of two‐dimensional Sr(Ag1−
x Lix )2Se2layered phases. With increased LiOH/LiCl ratio or reaction temperature, Li partially substituted Ag to form solid solutions of Sr(Ag1−x Lix )2Se2withx up to 0.45. In addition, a new type of intergrowth compound [Sr3Se2][(Ag1−x Lix )2Se2] was synthesized upon further reaction of Sr(Ag1−x Lix )2Se2with SrSe. Both Sr(Ag1−x Lix )2Se2and [Sr3Se2][(Ag1−x Lix )2Se2] exhibit a direct band gap, which increases with increasing Li substitution (x ). Therefore, the band gap of Sr(Ag1−x Lix )2Se2can be precisely tuned via fine‐tuningx that is controlled by only the flux ratio and temperature. -
more » « less
Abstract Synthesizing solids in molten fluxes enables the rapid diffusion of soluble species at temperatures lower than in solid‐state reactions, leading to crystal formation of kinetically stable compounds. In this study, we demonstrate the effectiveness of mixed hydroxide and halide fluxes in synthesizing complex Sr/Ag/Se in mixed LiOH/LiCl. We have accessed a series of two‐dimensional Sr(Ag1−
x Lix )2Se2layered phases. With increased LiOH/LiCl ratio or reaction temperature, Li partially substituted Ag to form solid solutions of Sr(Ag1−x Lix )2Se2withx up to 0.45. In addition, a new type of intergrowth compound [Sr3Se2][(Ag1−x Lix )2Se2] was synthesized upon further reaction of Sr(Ag1−x Lix )2Se2with SrSe. Both Sr(Ag1−x Lix )2Se2and [Sr3Se2][(Ag1−x Lix )2Se2] exhibit a direct band gap, which increases with increasing Li substitution (x ). Therefore, the band gap of Sr(Ag1−x Lix )2Se2can be precisely tuned via fine‐tuningx that is controlled by only the flux ratio and temperature. -
more » « less
Abstract Cooperative cluster metalation and ligand migration were performed on a Zr‐MOF, leading to the isolation of unique bimetallic MOFs based on decanuclear Zr6M4(M=Ni, Co) clusters. The M2+reacts with the μ3‐OH and terminal H2O ligands on an 8‐connected [Zr6O4(OH)8(H2O)4] cluster to form a bimetallic [Zr6M4O8(OH)8(H2O)8] cluster. Along with the metalation of Zr6cluster, ligand migration is observed in which a Zr–carboxylate bond dissociates to form a M–carboxylate bond. Single‐crystal to single‐crystal transformation is realized so that snapshots for cooperative cluster metalation and ligand migration processes are captured by successive single‐crystal X‐ray structures. In3+was metalated into the same Zr‐MOF which showed excellent catalytic activity in the acetaldehyde cyclotrimerization reaction. This work not only provides a powerful tool to functionalize Zr‐MOFs with other metals, but also structurally elucidates the formation mechanism of the resulting heterometallic MOFs.
