本研究采用简单的水热法得到了单一形态学和小尺寸分布的油溶性PbSe量子点。所得到的立方相PbSe量子点颗粒呈现近球形，且平均颗粒尺寸为4.0±0.5 nm。PbSe量子点在435 nm近紫外区域呈现出较强的和相对较窄的光致发光光谱，光谱的半高宽值约为80 nm。随着反应时间的延长和反应温度的升高，发光光谱向低能量区域移动，谱峰的半高宽也随之变大。在改变前驱体Pb/S摩尔比的条件下，发光光谱相对强度降低，光谱也发生向长波长区域移动。另外，随着反应温度和前驱体Pb/S摩尔比的改变， PbSe量子点颗粒表面的缺陷也增多。在反应过程中，小颗粒长大成大尺寸颗粒促使 PbSe 量子点的发光光谱向长波长移动，这个现象符合奥斯瓦尔德熟化定律。热力学不稳定和颗粒表面低浓度油酸包覆也造成PbSe量子点颗粒表面产生缺陷。
Oil-soluble PbSe quantum dots (QDs) with uniform morphology and narrow size distribution were ob-tainedvia a facile hydrothermal approach. The cubic PbSe QDs with nearly spherical shape and average diameter of (4.0 ± 0.5) nm were obtained. The as-synthesized PbSe QDs showed a strong and a relatively narrow band edge emis-sion in the near purple region at 435 nm and a small full width at half maximum (FWHM) approximately of 80 nm. The photoluminescence (PL) spectra moved to low energy region and FWHM became broad when the reaction time extended and the synthesis temperature increased. The PL spectra exhibited less intense and well defined features at long wavelength which were ascribed to low energy transitions as varying Pb/S molar ratios. In addition, the defect luminescence of PbSe QDs became more obvious with the synthesis temperatures and Pb/S molar ratios increasing. The PL spectra of PbSe QDs shifted to long wavelength (low energy region), because small particles coalesced into form large particles during reaction, which was in agreement with the Ostwald ripening principle. The defects of PbSe QDs may result from thermodynamically instable and lower densities of capped oleic acid.
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