Synthesis, Characterization, and Optical Properties of Organic–Inorganic Hybrid Layered Materials: A Solvent-Free Ligand-Controlled Dimensionality Approach Based on Metal Sulfates and Aromatic Diamines

Abstract

A new family of organic–inorganic hybrid layered materials based on cadmium and zinc sulfates was synthesized using 1,2-phenylenediamine (OPD), 1,3-phenylenediamine (MPD), and 1,4-phenylenediamine (PPD) as organic templates and ligands. The diamines act as structure-directing agents to obtain one-dimensional (1D), 2D, and 3D frameworks. Six new materials were obtained utilizing a simple, solvent-free synthesis approach: 1D: (OPD)2ZnSO4 1, (OPD)2CdSO4 2; 2D: (MPD)2ZnSO4 3, (MPD)2CdSO4 4; 3D: (PPD)­ZnSO4 5, (PPD)­CdSO4 6. The synthesis method proved to be scalable and robust. The crystal structures were determined using data from X-ray powder diffraction measurements (XRPD). It was observed that the type of amine determines the dimensionality of the obtained materials. 1D, 2D, and 3D structures were obtained using ortho-, meta-, and para-phenylenediamine isomers, respectively. The phase purity of the samples was confirmed by elemental analysis, and the morphology of the crystallites was studied using scanning electron microscopy. The thermal stability was determined by thermogravimetry and nonambient XRPD techniques. Additional characterization was performed for the two non-centrosymmetric, polar materials 3 and 4. Second-order nonlinear optical properties were examined using both experimental measurements (second harmonic generation) and theoretical calculations.

Dimethylaniline-Based Hybrid Compounds of Cadmium Diiodide: Synthesis, Crystal Structure, and Physical Properties

“…Both CdI 2 (2,5-DMA) 2 and CdI 2 (2,6-DMA) 2 were found to be optically stable and their SHG signal is greater than that of urea reference. For comparison, the SGH signal of a compound of cadmium sulfate with m -phenylenediamine reported by our team in 2018 is 8 times lower than the signal of KDP and for the same experimental conditions the SHG response for KDP is 9 times smaller than that for urea powder. The investigated compounds are also easy to obtain as powders, thermally stable under normal conditions (up to around 100 °C), transparent in the visible region of the spectrum, and sparingly soluble in water.…”

“…Hybrid organic–inorganic compounds play a significant role in the construction of advanced functional materials due to their structural diversity, mechanical stability enhanced by the inorganic part, and electronic properties provided by organic ligands. , Such compounds can be designed with various properties in mind, such as catalytic activity, magnetism, electrical conductivity, etc. − Among the properties exhibited by organic–inorganic compounds, there are nonlinear optical (NLO) effects, the presence of which gives hope for their potential use in optoelectronic devices. , A particular NLO effect of degenerate sum-frequency generation results in the appearance of the second harmonic light due to annihilation of two photons with a certain frequency, ω, and emission of a single photon with doubled frequency, 2ω.…”

Tuning magnetic properties by crystal engineering in a family of coordination polymers based on Ni(ii) sulphates

“…29 The diffraction pattern and lattice parameters were similar to those found for analogous compounds based on zinc sulphates and phenylenediamine previously reported by us. 25 Therefore, the crystal structures of the previously investigated materials were used as starting models to refine the crystal structures of 1-3. The structure refinement was performed using the 'profile method' [30][31][32] using the JANA2006 33 program.…”

“…Although many such methods exist, the degree of control over the compounds finally obtained varies between different approaches. [22][23][24] To contribute to the crystal engineering of hybrid materials, we have shown strong interest in compounds based on Zn and Cd sulphates and phenylenediamine isomers (ortho, meta and para) 25 where a correlation between the isomer used and the dimensionality of the obtained structure was reported. Currently, we take advantage of the variety of dimensions in this family of compounds to investigate the magneto-structural correlations.…”

Benzene-1,2-diaminium bis(4-methylbenzene-1-sulfonate)

“…The aromatic diamine, benzene-1,2-diamine also known as o-phenylenediamine, can function as a neutral ligand and bind to a metal via both amine N atoms (Koizumi & Fukuju, 2011;Guillé n et al, 2018) or by a single nitrogen in a monodentate fashion (Nelson et al, 1982;Dickman, 2000). In addition, benzene-1,2-diamine can function as a charge-balancing dication in which both the amine N atoms are protonated (Raghavaiah et al, 2006;Powers & Geiger, 2019) or as a monocation (Raghavaiah et al, 2005;Mishra & Pallepogu, 2018).…”