Addition/Correction pubs.acs.org/cm
Correction to Quantifying Cation Exchange of Cd2+ in ZnTe: A Challenge for Accessing Type II Heterostructures Michael J. Enright, Harrison Sarsito, and Brandi M. Cossairt* Chem. Mater. 2017, 29 (2), 666−672. DOI: 10.1021/acs.chemmater.6b04215 S Supporting Information *
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e are issuing a correction for the reported elemental ratios obtained using ICP-AES. The ratios are reported as mass ratios as opposed to relative mole ratios. This changes none of the major conclusions of the manuscript nor any of the rates or kinetic parameters measured. Notably, the reported ZnTe nanorod starting material has a molar tellurium to zinc ratio of 0.9:1.0. Additional corrections to the main text are provided below. Figure 3 in the main text as well as Figures S4
Figure 4. Pseudo-first-order rates for the loss of Zn2+ from ZnTe nanorods during cation exchange as a function of temperature. The yaxis measures the loss of Zn2+ from the nanorods, where −ln[Zn2+] = ln[(Zn,Cd)Te].
On page 671, paragraph 2, corrections are shown in bold: ICP-OES evaluation of the samples prepared here indicates a Zn:Cd:Te:Se ratio of 1.0:8.6:7.4:1.7 starting from a Zn:Te ratio of 1.0:0.5 in the starting quantum dot cores. [...] The zinc to tellurium ratio decreases dramatically to 1.0:7.4 after exposure to the cadmium and selenium precursors.
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Figure 3. Elemental composition of Cd2+ exposed ZnTe nanorods as a function of time and temperature. 2D plots are provided in the Supporting Information, Figure S4. Elemental composition is reported as a relative molar amount normalized against tellurium content in the nanorod structure. The relative [Zn2+] (green) decreases as an increasing rate as temperature is increased. Cadmium uptake, both through exchange with zinc (blue) and via surface adsorption (red), also occurs at a faster rate as temperature increases.
ASSOCIATED CONTENT
S Supporting Information *
The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acs.chemmater.7b00514. Additional experimental information and analysis to supplement the results and conclusions described in this report (PDF)
and S8 reported mass ratios but have been corrected below to reflect molar ratios. The y-axis of Figure 4 has also been adjusted to represent the molar ratios of zinc versus tellurium.
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CORRECTIONS TO REPORTED ELEMENTAL RATIOS IN THE MAIN TEXT On page 667, paragraph 1, of Results and Discussion: The molar ratio of tellurium to zinc is 0.9:1.0 in the starting ZnTe nanorods. On page 699, line 4: At room temperature all cadmium uptake through both mechanisms is completed within the first 10 s as the rod composition remains constant after that time, yielding a final composition of Zn:Cd:Te = 0.71:0.57:1. Based on the relative change in the Zn:Te ratio in the nanorods, 70% of the measured Cd2+ is incorporated through exchange with Zn2+ ions in the rod while the other 30% is adsorbed to the nanorod surface. © XXXX American Chemical Society
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DOI: 10.1021/acs.chemmater.7b00514 Chem. Mater. XXXX, XXX, XXX−XXX
