Generalized chemical route to develop fatty acid capped highly dispersed semiconducting metal sulphide nanocrystals

Journal Article · Wed Aug 15 00:00:00 EDT 2012 · Materials Research Bulletin

DOI:https://doi.org/10.1016/J.MATERRESBULL.2012.04.007· OSTI ID:22215182

Patel, Jayesh D. ^[1]; Mighri, Frej ^[1]; Ajji, Abdellah ^[1]

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1. Center for Applied Research on Polymers and Composites, CREPEC, Quebec (Canada)

Highlights: ► Chemical route for the synthesis of OA-capped CdS, ZnS and PbS at low temperature. ► Synthesized nanocrystals via thermolysis of their metal–oleate complexes. ► Size quantized nanocrystals were highly dispersed and stable at room temperature. -- Abstract: This work deals with the synthesis of highly dispersed semiconducting nanocrystals (NCs) of cadmium sulphide (CdS), zinc sulphide (ZnS) and lead sulphide (PbS) through a simple and generalized process using oleic acid (OA) as surfactant. To synthesize these NCs, metal–oleate (M–O) complexes were obtained from the reaction at 140 °C between metal acetates and OA in hexanes media. Subsequently, M–O complexes were sulphurized using thioacetamide at the same temperature. Transmission electron microscopy (TEM) and X-ray diffraction (XRD) characterizations show that the synthesized products are of nanoscale-size with highly crystalline cubic phase. The optical absorption of OA-capped metal sulphide NCs confirms that their size quantization induced a large shift towards visible region. Photoluminescence (PL) spectrum of CdS NCs shows a broad band-edge emission with shallow and deep-trap emissions, while PL spectrum of ZnS NCs reveals a broad emission due to defects states on the surface. The thermogravimetric analysis (TGA) and Fourier transform infrared (FTIR) spectroscopy indicate that fatty acid monolayers were bound strongly on the nanocrystal surface as a carboxylate and the two oxygen atoms of the carboxylate were coordinated symmetrically to the surface of the NCs. The strong binding between the fatty acid and the NCs surface enhances the stability of NCs colloids. In general, this generalized route has a great potential in developing nanoscale metal sulphides for opto-electronic devices.

• OSTI ID: 22215182
• Journal Information: Materials Research Bulletin, Vol. 47, Issue 8; Other Information: Copyright (c) 2012 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0025-5408
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
77 NANOSCIENCE AND NANOTECHNOLOGY
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
CADMIUM
CADMIUM SULFIDES
ELECTRONIC EQUIPMENT
FOURIER TRANSFORMATION
INFRARED SPECTRA
LEAD SULFIDES
NANOSTRUCTURES
OLEIC ACID
PHOTOLUMINESCENCE
SEMICONDUCTOR MATERIALS
SURFACES
SYNTHESIS
THERMAL GRAVIMETRIC ANALYSIS
TRANSMISSION ELECTRON MICROSCOPY
X-RAY DIFFRACTION
ZINC SULFIDES