Structural Extension from 0D to 3D Pillared Heterometallic 3d-4f Polyoxometalate Hybrids

Abstract

Four 3d−4f heterometallic pillared polyoxometalate hybrids, namely, [Ln 2 Cu(SiW 12 O 40 )(Hina) 4 4) Eu (3), (5), Hina = isonicotinic acid), were synthesized under hydrothermal conditions inspired by a structure of zero-dimensional (0D) Tb-based polyoxometalate [Tb 2 (ina) 2 (Hina) 6 (H 2 O) 2 ](SiW 12 O 40 ) (1). Structural analysis of 1 reveals that all the N atoms of ina ligands are uncoordinated and can serve as potential coordination sites to bridge transition metals. So, the copper cation was introduced into the reaction system, and 2−5 realized the structural extension from 0D to threedimensional pillared structures in which the two-dimensional sheets were composed of [Ln1 2 (Hina) 4 (ina) 4 (H 2 O) 2 ] or [Ln2 2 (Hina) 4 (ina) 4 (H 2 O) 4 ] and [SiW 12 O 40 ] acted as pillars. In addition, all these compounds are characterized by X-ray diffraction, IR, thermogravimetric, UV−vis, and solid-state photoluminescence spectra.

Recent progress in polyoxometalate–viologen photochromic hybrids: structural design, photochromic mechanism, and applications

“…[1][2][3][4][5][6][7][8][9][10][11][12][13][14][15] Polyoxometalates (POMs) are a class of very important photochromic materials due to their good redox properties and photoactivity, and readily undergo photoinduced electron transfer to form Mo/W(V)-containing heteropolyblue. [16][17][18][19][20][21][22][23][24][25][26][27][28][29] In general, purely inorganic POMs have poor photochromic behavior and are difficult to synthesize, while purely organic photochromic materials have poor fatigue resistance and high temperature resistance despite their fast response and rich color, 30,31 so it has been difficult to find new photochromic materials in pure organic or inorganic systems. By contrast, organic-inorganic hybrid photochromic materials can not only maintain or even enhance the properties of the respective components, but also generate new properties based on the synergistic effect between the components, which is more attractive to researchers.…”

Enhanced Fluorescence of La3+, Gd3+ doped EuW10 for Temperature sensing performance

“…[39] Two competing concentration effects may occur when La 3 + ions were doped into EuW 10 . [11] The effective content of Eu 3 + ions (luminescence center ions) decrease with the increase of the relative content of La 3 + ions, which leads to the decrease of the luminescence intensity. Meantime, the 4 f orbital of the La 3 + ions are empty with no f-f transition, thus no electrons are excited.…”

“…The temperature sensing mechanism of temperature-sensitive paints: Generally, excited state molecules return to the ground state through the process of radiation (k r ) and non-radiation (k nr ), and the non-radiation process is the key to the temperature sensing performance (Figure 8). [11] Probe molecules are excited by absorbing energy and collide with other particles. The collision behavior converts part of the energy into heat.…”

“…Because of the special shape, size and rich structure topology, POMs are widely used in magnetism, photoluminescence, catalysis, pharmaceutical chemistry and other research fields. [9][10][11][12][13][14] Recently, POMs can connect Ln 3 + ions to construct Ln-POMs as classical inorganic ligands. POMs can be used as emission antenna ligands to sensitized Ln 3 + ions.…”

Chiral wheel anions of copper(ii)-early lanthanides(iii) with high optical-limiting properties

“…In recent work, we showed that a number of tartratocuprate complexes with defined structures can be assembled. [34][35][36][37] For instance, the use of guanidinium cations as structure directing agents (SDAs) and multiple ligands gives rise to 2D-layered frameworks {Cu II 32 } n and complex clusters {Cu II 48 }, respectively (Fig. 1).…”