Sains Malaysiana 39(3)(2010): 473–477

Synthesis of CdTe-CdSe Core-Shell Quantum Dots with Luminescence in the Red

(Sintesis Titik Kuantum Teras Dalaman-luaran CdTe-CdSe yang Memberikan Luminesen Merah)

Norhayati Abu Bakar, Akrajas Ali Umar*, Muhamad Mat Salleh

Institute of Microengineering and Nanoelectronics(IMEN)

Universiti Kebangsaan Malaysia 43600 Bangi, Selangor D. E., Malaysia

Muhammad Yahaya

School of Applied Physics, Faculty of Science and Technology

Universiti Kebangsaan Malaysia 43600 Bangi,  Selangor D.E. Malaysia

Received: 7 May 2009 / Accepted: 9 November 2009

ABSTRACT

This paper reports on the synthesis and characterization of CdTe-CdSe core-shell quantum dots (QDs) with luminescent from 650 to 720 nm. The QDs were synthesized using a wet-chemical process at a moderate temperature (300 °C) following two-steps process of core and shell synthesis. The photoluminescence characterization on the QDs showed that the QDs emitted light in the range of red regime with quantum yield as high as 37%. Owing to their unique photoluminescence characteristics (high quantum yield and narrow spectrum), the QDs may find a potential application in a variety of applications such as LED, solar cell and bio-labeling.

Keywords: CdTe-CdSe core-shell; narrow spectrum; photoluminescence; quantum dots; quantum yields.

ABSTRAK

Kertas ini melaporkan tentang penyediaan dan pencirian titik kuantum teras dalaman-luaran CdTe-CdSe yang memberikan luminesen pada julat 650 hingga 720 nm. Titik kuantum disintesis menggunakan proses kimia-basah pada suhu sederhana (300 °C) melalui dua tahapan proses iaitu sintesis teras dalaman dan luaran. Pencirian fotoluminesen ke atas titik kuantum menunjukkan bahawa titik kuantum menunjukkan pancaran pada kawasan merah dengan hasil kuantum setinggi 37%. Keunikan ciri fotoluminesen titik kuantum membolehkan titik kuantum berpotensi digunakan dalam pelbagai aplikasi sepertiLED, sel solar dan bio-label.

Kata kunci: CdTe-CdSe; fotoluminesen; hasil kuantum; spektrum sempit; titik kuantum

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*Corresponding author; email: akrajas@ukm.my