Structural, spectroscopic, luminescence sensing and TD-DFT theoretical studies of a CuP2N-type complex.

Luminescent cuprous complexes are an important class of coordination compounds due to their relative abundance, low cost and ability to display excellent luminescence. The title heteroleptic cuprous complex, [2,2'-bis(diphenylphosphanyl)-1,1'-binaphthyl-κ2P,P'](2-phenylpyridine-κN)copper(I) hexafluoridophosphate, rac-[Cu(C44H32P2)(C11H9N)]PF6, conventionally abbreviated rac-[Cu(BINAP)(2-PhPy)]PF6 (I), where BINAP and 2-PhPy represent 2,2'-bis(diphenylphosphanyl)-1,1'-binaphthyl and 2-phenylpyridine, respectively, is described. In this complex, the asymmetric unit consists of a hexafluoridophosphate anion and a heteroleptic cuprous complex cation, in which the cuprous centre in a CuP2N coordination triangle is coordinated by two P atoms from the BINAP ligand and by one N atom from the 2-PhPy ligand. Time-dependent density functional theory (TD-DFT) calculations show that the UV-Vis absorption of I should be attributed to ligand-to-ligand charge transfer (LLCT) characteristic excited states. It was also found that the paper-based film of this complex exhibited obvious luminescence light-up sensing for pyridine.

[Photocatalytic Oxidation of p-arsanilic Acid by TiO2].

The p-arsanilic acid (ASA) is an important organoarsenical compound and its removal is more difficult compared to inorganic arsenic, however, little attention has been paid to the removal of ASA in aqueous environment. The influence of P25 on the adsorption of ASA, effect of P25 dosage, pH and illumination intensity on the photo-catalysis, the production analysis and main mechanism of photo-degradation were investigated in this study. The results showed that in the P25 catalysis process, simulated natural light could degrade ASA into As (V) by oxidation. The total As was reduced to about 0.34 mg x L(-1) within 0.5 h under the following condition: the initial concentration of ASA was 2 mg x L(-1) and the dosage of TiO2 was 1 g x L(-1). The result showed that the removal rate of ASA in acidic conditions was much higher than that in alkaline conditions. The optimal strength of light was 68.5 mW x Cm(-2). Hydroxide radical played a major role in photocatalytic oxidation of ASA by P25.