Vol. 65, No. 6, June 2015, pp. 560∼570
Optical Properties of CdSe 0.6 Te 0.4 Nanostructures Fabricated by Altering the Order of Mixing Se 2- , Te 2- Precursor Solutions into the Cd 2+ Solution
Seong-Wook Park · Il-Gon Kim · Dong-Sun Yoo ∗
Department of Physics, Changwon National University, Changwon 641-773, Korea (Received 16 April 2015 : revised 8 May 2015 : accepted 12 May 2015)
We synthesized CdSe
0.6Te
0.4QDs by adding Se
2−and Te
2−to a Cd
2+solution, and we inves- tigated the optical properties of QDs fabricated by altering the order of adding Se
2−, Te
2−to the Cd
2+solution. When the Se
2−was added to the Cd
2+solution prior to the Te
2−, the core/shell structures of 2 nm in size were formed in 2 min, photoluminescence (PL) peak were observed at a wavelength of 600 nm. However, the size increase was no longer maintained after 2 min. When the Te
2−was added before the Se
2−, gradient-type alloyed QDs were formed. The growth of these QDs was continued until the PL peak was observed at 692 nm, and this structure was shown to be the most stable. If Se
2−and Te
2−were added simultaneously, QDs with an alloyed structure were also formed; however, the quality of the QDs were not as good as it was in the previous case. We verified that gradient-type CdTeSe alloyed QDs of good quality could be synthesized easily only by adding Te
2−to Cd
2+prior to adding Se
2−.
PACS numbers: 78.20.Ci
Keywords: Adding order of precursor solutions, CdTeSe core/shell structure, Alloyed QD, Gradient structure
¹
Å ö n Úù m Ç (Se 2- , Te 2- )8 ý ¼# b Å U Ø" e; c  \ ¥ CdSe 0.6 Te 0.4 x ¢ º8 ý
° Ë
Ñ] K ¡X ì Ä ¤V R Ë
) ç ] 8 ; · » G B# Þ · ¤ ò 6 B` 9 ∗
½ Ó" é ¶ @ / < Æ § Ó ü t o < Æõ , ½ Ó" é ¶ 641-773
(2015¸ 4 Z 4 16{ 9 ~ Ã Î6 £ §, 2015¸ 5 Z 4 8{ 9 Ã º& ñ : r ~ Ã Î6 £ §, 2015¸ 5 Z 4 12{ 9 > F S X & ñ )
Cd
2+6 xÓ oõ Se
2−, Te
2−6 xÓ o` ¦ ì ø Í6 £ x r & CdSe
0.6Te
0.437 á x- ½ + Ë ª & h ` ¦ ½ + Ë$ í % i ¦ Cd
2+6 x Ó
o\ Se
2−, Te
2−6 xÓ o` ¦ È Ò# H í H " fë ß ` ¦ Ë ¨# Q, ª & h _ Ó ü t$ í o\ ¦ ¸ % i . Se
2−6 xÓ o` ¦
$ È Ò# ¦, 10 í Ê ê\ Te
2−6 xÓ o` ¦ È Ò# ô Ç â Ä º 2 ì r Ê ê 2 nm ß ¼l _ CdTe/CdSe ï# Q/,
| 9
½ ¨ ¸_ ª & h s + þ A$ í ÷ & H X < s [ þ t É r 660 nm \ " f µ 1 Ï F g x ß ¼\ ¦ Ðs 9 8 s © $ í © t · ú § H .
Te
2−6 xÓ o` ¦ $ È Ò# ¦, × æ \ Se
2−6 xÓ o` ¦ È Ò# H â Ä º 60 ì r s © t $ í © s t 5 Å q ÷ & 9 (µ 1 Ï F
g x ß ¼: 692 nm) © î ß & ñ ) a q » 1 Ï+ þ A ½ + ËF K ½ ¨ ¸ + þ A$ í ) a . Se
2−6 xÓ oõ Te
2−6 xÓ o` ¦ 1 l x r \ È Ò#
½
+ É â Ä º\ ¸ q » 1 Ï+ þ A ½ + ËF K ½ ¨ ¸ + þ A$ í ÷ &t ë ß Te
2−6 xÓ o` ¦ $ È Ò# ô Ç â Ä º\ q K s Ý ¼ $ í © É r é
H o÷ & 9 ª ´ òÖ ¦ % i r b # Q . Cd
2+ü < Te
2−\ ¦ $ ì ø Í6 £ x r v H B Ä º é ß í H ô Ç ~ ½ ÓZ O \ _ K ª | 9 _
CdTeSe q » 1 Ï+ þ A ½ + ËF K ½ ¨ ¸_ ª & h ` ¦ ½ + Ë$ í ½ + É Ã º e % 3 .
PACS numbers: 78.20.Ci
Keywords: ½ ¨Ó ü t| 9 È Ò# í H " f, CdTeSe ï# Q/, | 9 ½ ¨ ¸, ½ + ËF K+ þ A ª & h , q » 1 Ï ½ ¨ ¸
∗
