SYNTHESIS, CHARACTERIZATIONANDPHOTOLUMINESCENCE PROPERTIES OF AgN- CO DOPED CdS NANOPARTICLES

Abstract

It was demonstrated in earlier studies that the use of methanol as a solvent leads to a strong enhancement of PL intensity of CdS quantum dot for use in optoelectronic devices. Likewise, the present study makes use of this principlein the investigation of the photoluminescence properties of CdS nanoparticles synthesized by solgelmethod. CadmiumSulphide (CdS) Nanoparticles were synthesized directly from cadmium nitrate (Cd(NO3)2and sodium sulphide (Na2S) precursors. Modified silver doped, nitrogen doped and silver nitrogen codoped cadmium sulphide were synthesized from CdS by treating it with silver nitrate and urea. The as-synthesizedNanoparticles were investigated byX-ray diffraction(XRD),Fourier transform infraredspectrometer(FTIR),UV– Vis spectrophotometers and photoluminescence(PL) spectrophotometer to study Structure and band gap determinations respectively.The crystallite sizes of cadmium sulfide and doped CdSnanocrystals were estimated from the peaks of XRD. The X-ray diffraction patterns indicate hexagonal structure of CdS. The optical properties of the samples were estimated by UV visible spectroscopy. Optical properties revealed a change in the band gap energy of CdS, N-doped CdS,Ag-doped CdS and AN co-doped CdSnanocrystals were 2.43, 2.38,2.23 and 2.10eV respectively due to size effect. The Blue shift observed in the photoluminescence (PL) spectrum of doped CdS can be attributed due to Size and doping effects.Studies of the photoluminescence properties of these materials were conducted using fluorescence spectrophotometer with in the wave length range of 200-800 nm and the spectral bands(peaks) of the respective samples were analyzed and The results obtained as such showed that both doping and co doping of the CdS have increased significantly its photoluminscience proporties .