Preparation and characterization of ultrafine zinc sulfide particles of quantum confinement

Optical excitations in stoichiometric uncapped ZnS nanostructures

“…Wu et al report a synthesis where b-cyclodextrin encapsulates the ZnS nanostructures that display a strong absorption peak at approximately 250 nm (5 eV). 5 Finally, syntheses in the presence of capping agents 6,7 display absorption peaks at approximately 265 nm (4.7 eV, mercaptoethanol), 239 or 260 nm (5.2 or 4.8 eV, 1-thioglycerol) and 230 or 265 nm (5.4 or 4.7 eV, 1-thiophenol). Similar changes have also been observed for the luminescence spectra.…”

Preparation and purification of l-cysteine capped CdTe quantum dots and its self-recovery of degenerate fluorescence

“…One of the chief concerns in the synthesis of nanoparticles involves the methods to control the size and stability of these materials [8][9][10][11]. Size-selective precipitation [12][13][14], arrested precipitation [7], cages of molecular sieves [15], different starting pH [16] and exclusion chromatography [17] have been used to obtain nanoparticles within narrow size ranges. Some recent studies on the biologically formed nanoparticles suggested novel methods for the synthesis of apparently homogenous preparations of desired size range using appropriate capping reagent.…”

Quantum Size Effects in the Photonics of Semiconductor Nanoparticles

“…As follows from Eq. [142,143], Sb 2 S 3 [142], HgS [83,144,145], ZnS [37,76,83,129,[146][147][148][149][150][151][152][153][154][155][156][157], Zn 1-x Mn x S [157], In 2 S 3 [158,159], MoS 2 [160,161], PbS [33,37,58,59,76,77,110, [75,123,[189][190][191][192][193][194], PbO 2 [195], CeO 2 [134,196,197], Cu 2 O [198,199], VO 2 [200], selenides and composites based on themCdSe [20, 22, 24, 27, 30, 44-48, 91, 94, 96, 128, 141, 165, 201-232]...…”

“…Here, the smaller the particle becomes, i.e., the more strongly the exciton experiences spatial restriction, the larger the E ex value and the more clearly defined are the maxima of the exciton series in the absorption spectra of the semiconductor nanoparticles. Resolution of one or more exciton maxima in the absorption spectrum at room temperature is observed during the transition to the regime of quantum restriction in the crystals of such semiconductors as CdS [4, 21, 36, 40, 44, 76-78, 81-85, 89, 95, 103, 107, 114, 116, 123, 125, 138-141, 220, 221], PbS [59,164,166], ZnS [76,83,147,151], HgS [83], CdSe [4, 27, 44, 47, 141, 201, 202, 207, 210, 211, 218, 219, 223-232, 253, 293], CdSe x Te 1-x [231,[238][239][240], ZnSe [249], PbSe [64,122,123,241,242], CuInSe 2x Te 2(1-x) [252], CdTe [44,47,141,253,261,262,[265][266][267][268][269]294], ZnO [178,179,188,295], CuCl [4,278], PbI 2 [282], etc. The position of the exciton maxima in the absorption spectra of semiconductor nanocrystals can be calculated accurately using the second derivative of the spectral curve (Fig.…”