Preparing of CdSe quantum dots

Cilj ovog rada bio je provesti sintezu kadmij-selenidnih (CdSe) kvantnih točaka, te pokazati ovisnost zabranjene zone materijala o rastu čestica tj. o trajanju reakcije. Prethodno pripremljene prekursorske otopine selenija i kadmija istovremeno se dodaju u otopinu za rast, vrući oktadecen, čime trenutačno započinje proces nastajanja i rasta kvantnih točaka. Kinetičkom analizom na temelju spektroskopskih podataka određeni su parametri rasta nanočestica. Reakcijska smjesa uzorkovana je u određenim vremenskim razmacima kako bi se pripravile kvantne točke u širokom rasponu veličina tj. svojstava koja se očituju u različitim spektrima. Modelna solarna ćelija na bazi fotoaktivnog sloja kadmij-selenidnih kvantnih točaka pripravljena je u sastavu ITO - ZnO – CdSe – PEDOT:PSS -Ag.The aim of this research was to synthesise cadmium selenide (CdSe) quantum dots, determine the dependence of the band gaps and to determine how reaction time influences the particle growth. Previously prepared cadmium and selenium precursor solutions were simultaneously introduced into the growth solution, hot octadecene, instantly initiating the reaction of formation and growth of the quantum dots. The parameters of the nanoparticle growth were determined by kinetic analysis based on spectroscopy data. Reaction mixture was sampled at certain time intervals in order to achieve a broad spectrum of quantum dot sizes and characteristics. Model solar cell based on photoactive layer made of cadmium selenide quantum dots was prepared as ITO – ZnO – CdSe – PEDOT:PSS – Ag