Band‐Edge Photoluminescence Recovery from Zinc‐Blende CdSe Nanocrystals Synthesized at Room Temperature

Abstract

Abstract Low‐cost, large‐scale production of highly photoluminescent semiconductor nanocrystals (NCs) is desirable for a variety of applications. In this paper we report the realization of highly photoluminescent zinc‐blende CdSe nanocrystals from room‐temperature water‐phase synthesis, followed by low‐temperature (80 ± 5 °C) chemical etching in a solution of 3‐amino‐1‐propanol/H 2 O ( v / v = 10/1). X‐ray diffraction (XRD) and transmission electron microscopy (TEM) data indicate that these CdSe NCs exhibit a cubic, zinc‐blende crystal structure. After etching, these CdSe nanocrystals show strong band‐edge photoluminescence (with quantum efficiency as high as 50 %) and lack of deep‐trap emissions. A high‐resolution TEM investigation suggests that this etching not only removes surface irregularities, but also attacks grain boundaries. Moreover, the size distribution reduces upon progressive etching to allow photoluminescence full‐width‐at‐half‐maximum (FWHM) values as low as 30 nm.