A Rare (3,4)‐Connected Chalcogenide Superlattice and Its Photoelectric Effect

Abstract

The usefulness of cadmium chalcogenide clusters and their organized superlattices in optical, electronic, and catalytic applications [1] has prompted researchers to synthesize cadmium chalcogenide nanostructures of different shapes and sizes. In particular, self-assembly of structurally well-defined cadmium chalcogenide clusters is of interest because their uniform sizes and precisely known structures allow the study of quantum-confinement effects and collective properties at the lower size limit of quantum-dot structures.[2-6] The availability of different cluster sizes and their various spatial organizations may lead to new applications in optoelectronic and catalytic applications.An interesting property of cadmium chalcogenides is their optical response. As photofunctional materials, the cadmium chalcogenide system has been widely studied in solar-energy conversion, semiconductor surface sensitization and modification, and nanoelectronics. Nanoelectronic devices, which may eventually replace microelectronics in communications and computer technology, require the size of a semiconductor to be reduced to nanoscale proportions. Such a size reduction will enhance its electronic, magnetic, and optical properties, and thus enable new applications. In the area of nanostructured materials, chalcogenide clusters such as [Cd 17 S 4 -(SPh) 28 ] 2À (called C1 cluster, the first member of the series of capped supertetrahedral clusters denoted as Cn, n = 1, 2, 3 …) and [Cd 32 Se 14 (SePh) 36 (PPh 3 ) 4 ] (C2) lie at the extreme lower limit of the size spectrum of nanoparticles.[7] Thus, the optical response of these individual clusters and their self-assembled covalent superlattices may have potential applications in nanoelectronics.Recent developments in metal chalcogenides have resulted in a number of 4-connected frameworks with topologies related to polymorphs of SiO 2 such as cristobalite and quartz. [5,[8][9][10] However, to our knowledge, no three-dimensional (3D) framework built from 4-and 3-connected cadmium chalcogenide clusters was known prior to this work. Three-connected centers, when present alone, tend to form low-dimensional structures. However, in combination with 4-connected centers, they can form interesting 3D openframework architectures.[11] Herein we report a novel 3D (3,4) 4 } n ] has the boracite-type topology and exhibits photoelectric behavior. Note that it is difficult to realize oxidebased framework topologies in chalcogenides because of the different bonding geometries surrounding S and O sites. Our research, however, demonstrates that when chalcogenide clusters are used as pseudo-atoms, more diverse oxide-based network topologies become accessible.Boracite, a magnesium chloroborate (Mg 3 B 7 O 12 Cl), is an interesting mineral with a (3,4)-connected net [12] based on corner-sharing BO 3 triangles and BO 4 tetrahedra. Boracite and its derivatives are of particular interest because of their polar structures and technological applications related to their unique piezoelectric, pyroelectric, ferroe...

Characterization of “Cd10S4(SPh)12”, the Thermal Decomposition Product of (NMe4)4[Cd10S4(SPh)16]: Synthesis of a Neutral Cd54 Sulfide Cluster and of a Polymeric Chain of Thiolate‐Bridged Cd17 Sulfide Clusters

“…[13] A 3D network is thus formed where each Cd 17 tetrahedron is sharing corners with four neighboring Cd 17 tetrahedra through µ 2 -SCH 2 CH 2 OH bridges. Similar 3D arrangements of clusters owing to bridging SPh groups was also found for Cd 17 [23] and Cd 32 [24] clusters. The structure of 3 is in between.…”

Metal Chalcogenide Clusters on the Border between Molecules and Materials

“…[23] The ''T3'' [24] structure of this cluster consists of four fused adamantane cages. The larger cluster [Cd 17 S 4 (SPh) 28 ] 2À was subsequently reported, [25] and the framework can be described as being built up from a cubic core of four central adamantane cages (sharing edges and one vertex), capped by four (hexagonal) barrelane cages (the overall structure denoted C1) (Fig. 4).…”

“…[26] A network of [Cd 17 S 4 (SPh) 24 (CH 3 OCS 2 ) 4/2 ] has also been described where the nanoclusters are connected from the four apical sites via bridging CH 3 OCS 2 ligands. [27] Most recently, a [Cd 17 S 4 (SPhMe-3) 28 ] 2À based, boracite like superlattice has been prepared using solvothermal techiniques. [28] X-ray analysis illustrated that the individual clusters are joined via corner sharing thiolate ligands.…”

“…[27] Most recently, a [Cd 17 S 4 (SPhMe-3) 28 ] 2À based, boracite like superlattice has been prepared using solvothermal techiniques. [28] X-ray analysis illustrated that the individual clusters are joined via corner sharing thiolate ligands. This network solid was shown to display photoelectric properties, demonstrating the promise of this class of molecule for future applications.…”

Effect of HNO3 Concentration on the Morphologies and Properties of Bi2WO6 Photocatalyst Synthesized by a Hydrothermal Method

“…Over the past decades, photocatalysis has attracted significant attention for the effective utilization of solar energy and the reduction of environmental pollution [1][2][3][4][5][6]. The degradation of dyes, for instance Rhodamine B (RhB), is a typical test that is used to measure the degradation efficiency and the performance of several photocatalysts such as CeO 2 , ZnO, Ag 3 PO 4 , TiO 2 [7][8][9][10][11][12][13][14][15][16].…”