Table 2.

Initial XPS determined surface elemental compositions and corrected XPS atomic percentages of CdSe/CdS/ZnS indicate the presence of an intermediate CdS layer between the stoichiometric CdSe cores and the ZnS shell.

	at%
	Initial XPS surface atomic percentages using the peak area subtraction method		Corrected XPS atomic percentages Based on equation (3)
Element	All elements	Core elements	Homogenous CdSe core and ZnS shell	Three layer model: CdSe/CdS/ZnS
C 1s	83.4±2.1
O 1s	5.7±0.9
Cd 3d	5.6±0.7	72.0	48.0	54.7
Se 3d	0.9±0.1	11.6	7.1	13.5
P 2p	0.6±0.1
Zn 2p3	0.08±0.02	1.0	2.2	4.4
S 2s	1.2±0.4	15.5	42.8	27.4
F 1s	2.5±1.6
Cd/Se	6.2	6.2	6.8	4.1
S/Zn	15.5	15.5	19.5	6.2