A new polymeric complex of silver(i) with a hybrid pyrazine–bipyridine ligand – synthesis, crystal structure and its photocatalytic activity

Abstract

The 2,3-bis(6 0 -methyl-2,2 0 -bipyridin-6-yl)pyrazine ligand L reacts with trifluoromethanesulfonate silver(I) to give a coordination polymer {[AgL](CF 3 SO 3 )} n in which metal ions are in a distorted tetragonal pyramidal coordination geometry. The complex has been characterized by spectroscopic techniques, elemental analysis, X-ray diffraction, and UV-Vis spectroscopy. The methylene blue (MB) degradation was studied using UV-Vis spectrophotometry. After 400 min of exposure to UV light MB was completely decomposed. Degradation of MB after exposure to sunlight was considerably slower: 34% after 400 min and 90% after 133 h. Photodegradation of the dye follows second-order kinetics. {[AgL](CF 3 SO 3 )} n is an active photocatalyst for MB degradation under UV-Vis and sunlight irradiation.

Synthesis, crystal structures and photocatalytic properties of four silver(I) coordination polymers based on semirigid bis(pyrazole) and carboxylic acid co-ligands

“…2a), provided by atom O2 of the l 2 -g 1 ,g 1 -ndc ligand (Ag1-O2 2.576(2) Å ), plus atoms the N1 and N4A from two different l 2 -L2 ligands with Ag1-N1 and Ag1-N4A distances of 2.162(2) and 2.157(2) Å , respectively. The values of the Ag-N and Ag-O bond lengths are in good agreement with those of similar Ag(I) complexes [36,37].…”

Photocatalytic Decontamination of Wastewater Containing Organic Dyes by Metal–Organic Frameworks and their Derivatives

“…[99] To revealt he underlying mechanisms, two possible initial routes are proposed for MB degradation by [(AgL)(CF 3 SO 3 )] n in which metal ions are in ad istorted tetragonal pyramidal coordination geometry.O nt he one hand, the formation of active radicals is related to the photoexcitation of the photocatalyst. [91] The direct absorption of photons( hvC > E g )b y [(AgL)(CF 3 SO 3 )] n could cause the excitation of e À in the CB and the generation of h + in the VB of [(AgL)(CF 3 SO 3 )] n .T he e À in the CB are captured by surface-adsorbed oxygen and thus areactive superoxide anion is formed, which eventuallysuppresses the recombination of photogenerated electrons and photogenerated holes.T he h + in the VB serves as the oxidizing species for MB degradation.…”

“…On the other hand, the self-sensitization of dyes is also responsible for degradation under illumination. [99] The MB loaded on the photocatalyst surface can absorbp hotons to the excited state (MB*) under visible-light irradiation (MB (ads) + hvC!MB* (ads) Figure 2a). [37a] The kinetic rate constant (K)o ft he pseudo-first-order model for MB degradation overM IL-88A (energyp ositions hown in Figure 2b)i nt he presence of H 2 O 2 is 0.176 min À1 ,w hich is over 17 times higher than that in the absence of H 2 O 2 (0.010 min…”

A new 2,6-di(anthracen-9-yl)pyridine ligand and its complexes with Ag(I) ions: Synthesis, structure and photocatalytic activity

“…1) (3), which we designed on being inspired by our previous experiences with helical [26] and polymeric silver(I) [25] complexes, performing complexation reactions with a metal:ligand ratio of 1:1. The photocatalytic activity of the Ag complexes 1-3 were also examined under UV-Vis light and sunlight.…”

“…As photocatalysts, TiO 2 and doped TiO 2 were commonly used [21]. TiO 2 /Ag [22] and a few Ag contained compounds were used as photocatalysts in MB decomposition, namely Ag[Li 1/3 Ti 2/3 ]O 2 and Ag[Li 1/3 Sn 2/3 ]O 2 synthesized from layered Li 2 Ti(Sn)O 3 using molten AgNO 3 [23], helical [24] and polymeric Ag(I) complexes with 2,3-bis(6 0 -methyl-2,2 0 -bipyridin-6-yl)pyrazine [25]. Much attention needs to be focused on achieving the utilization of visible light because of UV light accounts for only about 2-3% of the total sunlight, whereas visible light accounts for 45%.…”