Adsorption of poly(N-ethyl-4-vinylpyridine) on titanium dioxide colloidal film and particles

Abstract

U sklopu ovog diplomskog rada ispitan je utjecaj adsorpcije jakog polikationa poli(N-etil-4-vinilpiridina) (P4VP) na titanijev dioksid u obliku nanočestica te koloidnog filma. Određena su površinska svojstva titanijeva dioksida. Elektroforetskim raspršenjem svjetlosti određena je izoelektrična točka titanijeva dioksida, a potenciometrijskom kiselinsko-baznom titracijom točka nul-naboja. Metodom izotermalne titracijske kalorimetrije kvalitativno je okarakteriziran proces protonacije površinskih skupina titanijeva dioksida. Za određivanje površinskog potencijala titanijeva dioksida izrađene su elektrode s pločicama titanija presvučenim oksidnim slojem. Površina istih pločica okarakterizirana je mikroskopijom atomskih sila i optičkim mikroskopom. Adsorpcija polikationa P4VP-a praćena je metodom UV-Vis spektrofotometrije te je ispitana valjanost adsorpcijskih izotermi. Elektroforetskim i dinamičkim raspršenjem svjetlosti određeni su elektrokinetički potencijal i hidrodinamički promjer čestica titanijeva dioksida s adsorbiranim P4VP-om. Ispitan je utjecaj adsorbiranog P4VP-a na površinski potencijal titanijeva dioksida te na topologiju titanijeva dioksida.As part of this thesis, the influence of adsorption of strong poly(N-ethyl-4-vinylpyridine) (P4VP) on titanium dioxide in the form of nanoparticles and colloidal film was examined. Surface properties of titanium dioxide were determined. The isoelectric point of titanium dioxide was determined by electrophoretic light scattering and the point of zero charge by potentiometric acid- base titration. The process of protonation of titanium dioxide surface groups was qualitatively characterized by isothermal titration calorimetry. To determine the surface potential of titanium dioxide, electrodes with titanium plates coated with an oxide layer were made. The surface of the same plates was characterized by atomic force microscopy and optical microscopy. The adsorption of the polycation P4VP was monitored by UV-Vis spectrophotometry and the validity of the adsorption isotherms was tested. The electrokinetic potential and hydrodynamic diameter of titanium dioxide particles with adsorbed P4VP were determined by electrophoretic and dynamic light scattering. The influence of adsorbed P4VP on the surface potential of titanium dioxide and on the topology of titanium dioxide was examined