Synthesis of Highly Monodisperse CdSe Quantum Dots and Size Dependency of Optical Properties

Öz

Semiconductor quantum dots have wide application areas as they have unique electrical and optical properties. In recent years, CdSe quantum dots are one of the most preferred nanomaterials. Highly monodisperse zinc blend CdSe quantum dots were synthesized using hot injection method. The structure and optical properties of the samples were determined by UV-Vis, photoluminescence, XRD and TEM methods. As a result, the difference between 2S-1P absorption transitions did not change with particle size. However, the difference between 1S-2S and 1S-1P transitions were found to be inversely proportional to particle size.  The FWHM value of the photoluminescence spectrum of the smallest sample has decreased to 25 mm and Stokes shifts were observed to be 0.06 eV.

Anahtar Kelimeler

• CdSe,Quantum Dot,hot injection,optical absorption,photoluminescence,nanotechnology

Yüksek Oranda Eş Parçacık Boyutlu CdSe Kuantum Noktaların Sentezi ve Optiksel Özelliklerinin Parçacık Boyutlarına Bağlılığı

Öz

Benzersiz elektriksel ve optik özelliklerinden dolayı yarıiletken kuantum noktalar birçok uygulama alanına sahiptirler. Son yıllarda CdSe kuantum noktalar en fazla tercih edilen nanomalzemelerin başında yer almaktadır. Sıcak enjeksiyon metodunu kullanarak yüksek oranda eş parçacık boyutuna sahip ve altıgen tip bir simetriye sahip çinko blend kristal tipinde CdSe kuantum noktalar sentezlendi. Elde edilen numunelerin yapıları ve özellikleri UV-Vis, fotolüminesans, XRD ve TEM karakterizasyon metodlarıyla aydınlatıldı. 1S, 2S ve 1P absorbsiyon geçişleri ve Stoke kayma miktarlarının malzeme boyutlarıyla olan ilişkileri incelendi.

Anahtar Kelimeler

• CdSe,Kuantum nokta,sıcak enjeksiyon,optik soğurma,fotolüminesans,nanoteknoloji

Kaynakça

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