Accessing Binary CdE [E = S, Se, Te] and Ternary CdxZn1-xE [E = S, Se] Materials in Mesoporous Architectures Using Silylated-Chalco

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• 作者：Elizabeth A. Turner ; Harald R&ouml ; sner ; Yining Huang ; John F. Corrigan
• 刊名：Journal of Physical Chemistry C
• 出版年：2007
• 出版时间：May 24, 2007
• 年：2007
• 卷：111
• 期：20
• 页码：7319 - 7329
• 全文大小：448K
• 年卷期：v.111,no.20(May 24, 2007)
• ISSN：1932-7455

文摘

Binary cadmium chalcogenide materials (CdS, CdSe, and CdTe) have been successfully synthesized at roomtemperature in the mesoporous environments of MCM-41 and MCF (mesocellular foam) by utilizing silylated-chalcogen reagents [E(SiMe₃)₂, E = S, Se, Te] as an efficient delivery source of E^2-. The encapsulated materialsare easily prepared by the initial complexation of anhydrous cadmium acetate to ethylenediamine functionalizedmesoporous material. The subsequent addition of E(SiMe₃)₂ leads to the preferential formation of CdE materialswithin the host. The observed blue shift in absorption maximum is in agreement with the expected quantumconfinement of these materials given the nanometer dimensions of the mesoporous architecture. Mild thermaltreatment of CdS and CdSe composites demonstrates the ability to control particle growth under specifiedthermal conditions, ultimately leading to a red shift in absorption maximum upon increasing thermolysistemperature. The utility of silylated-chalcogen reagents was further demonstrated in the formation of ternaryCd_xZn_1-xE (E = S, Se) encapsulated in MCF. The addition of the molecular precursor, (N,N'-TMEDA)Zn(ESiMe₃)₂ (TMEDA = N,N,N',N'-tetramethylethylenediamine), to Cd-MCF yields Cd_0.33Zn_0.76S- andCd_0.34Zn_0.6Se-MCF materials, where the absorption maximum lies between that of the respective parent binarycomposites. All materials have been characterized by ¹³C CP-MAS NMR and UV-vis spectroscopy, high-resolution transmission electron microscopy, energy-dispersive X-ray, and nitrogen sorption analysis.