Wavelength between blue light and yellow light
The samples were ground with an agate mortar, then fired at 1550 ℃ for 10hours.
Result Analysis
Intensity according to fraction of Ce3+ ion : 0.15 > 0.21 > 0.09 > 0.03
Intensity is largest at 0.15. Why?
* Concentration Quenching :
Too much activator concentration
->Reabsorption of light increases
->non-radiactive transition incre
분광법이란 물질에서 방출되거나 물질이 흡수하는 light의 spectrum을 이용하여 물질을 구분해내는 방법이다. 특정 wavelength의 light의 absorption 혹은 emission으로부터 물질을 구분할 수 있게 된다. 이러한 원리는 물질의 에너지가 특정 에너지 준위를 갖는다. 즉 양자화되어 있다는 가설에서 출발하는 것이다.
relatively high temperature, a nonradiative relaxation process
the transition probability per unit time, N :
By letting W by the luminescence probability, the luminescence efficiency h can by expressed as:
Incompletely filled 4 f shell
4 f orbital shielded from surroundings by the filled 5s2 &5p6 orbital
small influence of the host lattice to optical transition
Inorganic phosphor
○ A phosphor, most generally, is a substance that exhibits the phenomenon of luminescence.
○ Phosphors are often transition metal compounds or rare earth compounds of various types.
○“Classical” inorganic phosphors usually consist of a host lattice with activator ions doped into it in small concentrations, typically a few mole percent or less.
Host lattice &
2. Spectrophotometer를 이용한 growth curve확인 실험
1) D.W를 cuvette에 3ml을 넣는다.
2) Blank값 설정을 위해 0번 자리에 넣고 wavelength를 측정한다.
3) Sample liquid medium(0min)을 cuvette에 3ml을 넣는다.
4) 1번 자리에 넣고 wavelength를 측정한다.
(파장 370nm을 측정 파장으로 정함)
5) O.D. 값을 측정한다. (3번 반복 측정해서