Date of Award

Spring 5-10-2019

Level of Access

Open-Access Thesis

Degree Name

Master of Science (MS)

Department

Chemistry

Advisor

Scott Collins

Second Committee Member

Robert Pike

Third Committee Member

Matthew Brichacek

Abstract

In this thesis luminescent materials are studied. The luminescent materials studied are lanthanide complexes and group 11 iodide sensing abilities. Emission intensity of the lanthanide complexes through direct excitation of the lanthanide ion are relatively weak. To overcome this, three unique organic ligands were utilized to synthesize lanthanide nitrate complexes in which higher emission intensity can be observed via the antenna effect. Increased emission intensity resulted for EuIII and TbIII complexes for each ligand except triphenylphosphane oxide (only the TbIII complex demonstrated increased emission intensity). Latva’s empirical rule allows for the antenna effect to occur, in which energy is transferred from the triplet state of the organic ligand, to occur only for Ln3+ ion. In the case where Latva’s empirical rules does not apply, energy transfer from the excited singlet state of the organic ligand can transfer energy into the Ln3+ ion as demonstrated by ligands triphenylarsane oxide and bis(diphenylphosphino)ethane dioxide coordinating to the lanthanide nitrates. In the second part of the thesis, the vapochromic behavior of heterometallic and homometallic nanoparticles are observed upon the exposure to various nucleophilic vapors. Nucleophilic vapors can be detrimental to human health and are present in both lab and household environments. Cuprous iodide nanoparticles and iodocuprate(I)/argenate(I) nanoparticles of different metal content ratios are synthesized and characterized through powder X-ray diffraction and diffuse reflectance spectroscopy. These systems demonstrate distinct changes in emission color upon exposure to similar aromatic nucleophilic vapors. The emitting species upon exposure is identical for all systems and contains homogenous blend. Kinetic studies utilizing dimethyl sulfide as the nucleophilic vapor were carried out to develop a two-step vapochromic reaction mechanism. Through these studies it was revealed that increased silver(I) content results in a more rapid formation of the emissive product as compared to the pure cuprous iodide system. This study demonstrates that mixed metal salts surpass the sensing capabilities over single metal iodide analogs.

Share