2D Cu(I)-I Coordination Polymer with Smart Optoelectronic Properties and Photocatalytic Activity as a Versatile Multifunctional Material

Abstract

This work presents two isostructural Cu­(I)-I 2-fluoropyrazine (Fpyz) luminescent and semiconducting 2D coordination polymers (CPs). Hydrothermal synthesis allows the growth of P-1 space group single crystals, whereas solvent-free synthesis produces polycrystals. Via recrystallization in acetonitrile, P21 space group single crystals are obtained. Both show a reversible luminescent response to temperature and pressure. Structure determination by single-crystal X-ray diffraction at 200 and 100 K allows us to understand their response as a function of temperature. Applying hydrostatic/uniaxial pressure or grinding also generates significant variations in their emission. The high structural flexibility of the Cu­(I)-I chain is significantly linked to the corresponding alterations in structure. Remarkably, pressure can increase the conductivity by up to 3 orders of magnitude. Variations in resistivity are consistent with changes in the band gap energy. The experimental results are in agreement with the DFT calculations. These properties may allow the use of these CPs as optical pressure or temperature sensors. In addition, their behavior as a heterogeneous photocatalyst of persistent organic dyes has also been investigated.

Copper(i) iodide coordination polymers with triazole substituted pyridine ligands: photophysical and electrical conductivity properties

“…Pilar Amo-Ochoa et al reported that [Cu 2 I 2 (Fpyz)] n and [Cu(Cl-HIN)I] n CPs having Cu 2 I 2 chains present better conductivity ( σ ∼ 10 −5 S cm −1 ) than CP1 due to shorter Cu–I distances. 70,71 Some previously reported Cu( i ) CPs, having a Cu 2 I 2 double chain, similar to CP1 , have been reported to show electrical conductivity in a similar range. 65,72–75 A comparison of the electrical conductivities of CP1 with some previously reported CPs bearing a Cu 2 I 2 core is presented in Table S8 (ESI†), suggesting comparable values for CP1 .…”

Semiconducting Copper(I) Iodide 2D-Coordination Polymers for Efficient Sunlight-Driven Photocatalysis in Dye Degradation

“…Adsorption and chemical and biological oxidation are some techniques that have been used to remove organic dyes from water. However, these methods are costly as well as time-consuming. ,− To develop sustainable material/catalyst for dye degradation, one must consider cost-effectiveness, design, market viability, technology, and environmental impact of the material.…”

“…Copper iodide (CuI) hybrid materials have attracted much attention and have been extensively explored in the past decade, thanks to their applications in different fields of material science. − The charge-neutral inorganic motif Cu n I n can take many different forms. CuI 1D chains, Cu 2 I 2 rhomboid dimers, and Cu 4 I 4 cubane tetramers are the most common secondary building units (SBUs), leading to the formation of zero-dimensional (0D) discrete clusters to one-dimensional (1D) extended chains, two-dimensional (2D) sheets, and three-dimensional (3D) networks. − Apart from the rich structural diversity, less toxicity, cost-effectiveness, unique luminescence, and semiconducting properties further increase the applicability of these hybrid materials. − …”