Thermal growing of organometallicprecursors in hexadecylamine[CdioSe4(SPh]16]n-Hkylahsingeing△(120-315°℃)Up to 2 hours280°℃190°C21June2014ICNEM&T
June 2014 ICNEM&T 21 n-alkylamine D (120 - 315 0C) [Cd10Se4 (SPh)16] 4- 190°C 1 2 3 4 5 6 7 8 9 280°C Thermal Growing Up to 2 hours Thermal growing of organometallic precursors in hexadecylamine
B-SyntheticroutebyMicrowaveActivationstocksolutionCadmiumstearateinTOP-SulfidedecaneReaction underN,atmosphereHeatingbymicrowaveat300w→PredeterminedTemperatureCNReaction time < 25 mnJune5)M.Fregnaux,D.Arl,S.Dalmasso,J.-J.GaumetandJ.-P.Laurenti,Phys.Chem.C2010114(41),731822
June 2014 ICNEM&T 22 B - Synthetic route by Microwave Activation Cadmium stearate in decane stock solution TOP-Sulfide Heating by microwave at 300W Predetermined Temperature Reaction time < 25 mn Reaction under N2 atmosphere (5) M. Fregnaux, D. Arl, S. Dalmasso, J.-J. Gaumet and J.-P. Laurenti, J. Phys. Chem. C 2010 114 (41), 7318
OpticalanalyzesforNCsCdSe(roomtemperature)PhotoluminescenceAbsorption(laserHe/Cd:2=325nm)CdSeNCs-RTCdSeNCs-RT(b)C (3.0 mm)313313°C(e(3.0 mm)291°C2.8nm)eoos291°C(2.8 mm)266°C2.5mm)266°C(2.5mm2294(2.3 nm)229°C(2.3mC (2.1 nm)96196°C (2.1 mm)30°C(1.8mm)180°C (1.8mm)2,02,22.42.62,02,22.42.62.82,8Energy (eV),Energy (eV)Pecomhination handslosetotheBarEvidenceofthequantum-sizeeffectrption:of quantcterorthetransitionJune
June 2014 ICNEM&T 23 Absorption Photoluminescence (laser He/Cd : l = 325 nm) Optical analyzes for NCs CdSe (room temperature) Bands specific of quantum confinement Recombination band close to the fundamental absorption: Excitonic character of the transition Evidence of the quantum-size effect
TransmissionElectronMicroscopy(TEM)*LEM3PhilipsFEICM200microscope*Collaboration withLABDRATOIRE DETUOEPE SIEAROHUCCTUREETDEORMATERIAUXVoperating at 200kVVequipedwitha Gatan CCDcameraVhighmagnification (~500000x)24June2014ICNEM&T
June 2014 ICNEM&T 24 Transmission Electron Microscopy (TEM)* Philips FEI CM 200 microscope operating at 200 kV equiped with a Gatan CCD camera high magnification (~ 500 000 x) *Collaboration with:
TEM analysesThermal growingthermiqueT=231CCdS stabilityOccurenceGauss ofOccurence0=3.7+/-0.5nmShapefactor:1.22Size (nm)MicrowavesyntheticprocessCdSMW220°C-5'TEM23.09.11dliches 02,03,0820diameter5.2±0.6nm150=5.2+/-0.6nm40Shapefactor:1.25620nmDiameter(nm)June2014ICNEM&T
June 2014 ICNEM&T 25 0 2 4 6 8 10 0 5 10 15 20 Occurence Size (nm) Occurence Gauss of Occurence d= 3,7 +/- 0,5 nm e=1,22 cliché 05 CdS stability thermique T=231°C 20 nm 2 3 4 5 6 7 8 0 5 10 15 20 Occurence Diameter (nm) diameter 5.2 ± 0.6 nm dispersity 11% ratio 1.2 CdS MW 220°C - 5' TEM 23.09.11 clichés 02,03,08 50 nm q = 5.2 +/- 0.6 nm Shape factor : 1.2 q = 3.7 +/- 0.5 nm Shape factor : 1.22 Thermal growing Microwave synthetic process TEM analyses