Energy transfer for some organic compounds doped in Sol-Gel material

العناوين الأخرى

انتقال الطاقة لبعض المركبات العضوية المطعمة في ال Sol-Gel

مقدم أطروحة جامعية

al-Ubaydi, Isra Adnan Abd Allah

مشرف أطروحة جامعية

al-Maliki, Firas Jawad K.

الجامعة

جامعة بغداد

الكلية

كلية العلوم

القسم الأكاديمي

قسم الفيزياء

دولة الجامعة

العراق

الدرجة العلمية

ماجستير

تاريخ الدرجة العلمية

2013

الملخص الإنجليزي

In the present work, bi-molecular energy transfer from Rhodamine110 (R110) laser dye as donor to Oxizen1 (Ox1) and Nile blue (Nb) dyes as acceptors have been studied.

These dye mixtures had been incooperated in silica xerogel and thin film as host material using suitable sol-gel reaction parameters.

Spray pyrolysis technique has been used to prepare a homogenous and transparent film samples.

The final samples have been prepared as a function of dye mixture concentrations.

Different techniques have been used to test the prepared samples such as FTIR measurements, true volume measurements by gas displacement method, thin film thickness measurements as well as the spectroscopic tests in the visible region of electromagnetic spectrum.

The energy transfer process from donor (R110) to acceptor (Ox1) and from donor (R110) to acceptor (Nb) has been observed through the recorded spectra.

The spectroscopic parameters of energy transfer, namely the energy transfer rate constant (KET), the half quenching concentration [A]1/2, the critical energy transfer distance (Ro) and the energy transfer efficiency, have been calculated as a function of acceptor concentration.

Stern-Volmer relation of energy transfer process has been proved, and the range values of (KET) and (Ro) indicate that the nonradiation resonance energy transfer is the dominant mechanism of dyes mixture doped in sol-gel matrices.

The energy transfer efficiency has been increased with the increasing of acceptor concentrations.

The experimental results of this research show that the maximum efficiency has been found to be 54% and 53% for (1×10-4 R110- 5×10-4 Ox1) and (1×10-4 R110- 5×10-4 Nb) mixtures, respectiviely, doped in silica xerogel.

This efficiency has been decreased to 44% and 47% for the same mixture recipes doped in silica thin films, and this decreasing may be due to the difference in pores size for the two types of samples according to the difference in thermal treatment.

The results show that the emission properties of acceptor molecules (Ox1 and Nb) can be enhanced using the dye mixing recipe in sol-gel matrices.

This may be due to the behavior of donor molecules that reducing the interaction between acceptor molecules (at high concentration levels), and thus reducing the fluorescence concentration quenching.

التخصصات الرئيسية

الفيزياء

عدد الصفحات

101

قائمة المحتويات

• APA
• MLA
• AMA

لغة النص

الإنجليزية

نوع البيانات

رسائل جامعية

رقم السجل

BIM-606939