Manganous ion dictated morphology change and ferromagnetism in CdS nanocrystals

Davydov splitting in cadmium vacancy emission, ferromagnetism and photosensitivity in manganese incorporated CdS nanocrystals

“…The percentage of both components has been calculated by the Short and Steward method. 14 A proper deconvolution 5,12,14 (explained in ESI †) of the XRD pattern (given in ESI, Fig. S1 †) indicates a mixture of phases; however, it is surprising to note that increasing the [Mn 2+ ] does not seem to inuence the percentage composition of hexagonal and cubic morphologies, which remain constant during the addition of manganese ions up to 5%.…”

“…5 In order to calculate the exact percentage of cubic and hexagonal phases in a given mixture, we need a pure cubic sample, which has been taken from surfactant/amine (CTAB/BD)-assisted CdS nanocrystals that do not contain manganese and are denoted by CTAB/BD/0% Mn 2+ /CdS as per our earlier work. 12 These nanocrystals have been considered as a reference or base material. The DSC depicts the nature of DSC curves for SLS/BD-and SLS/PD-assisted with and without manganese-doped CdS nanocrystals.…”

“…However, below this temperature, a magnetic transition is observed in both samples around 35 K, revealing the presence of ferromagnetism. 12 This is further conrmed by measuring hysteresis as a function of temperature. The pre-annealed sample shows a very low measured hysteresis value of $410 Oe at 2 K. On the other hand, the post-annealed sample shows a clear loop with measured hysteresis value of 1750 Oe at 2 K and the value is very low at 50 K as shown in Fig.…”

“…9,10 Although there are a large numbers of publications involving Mn-based semiconductors, specically Cd 1Àx Mn x S, we have investigated the properties of such nanocrystals with various Mn compositions with our method of synthesis and attempted to understand their new or modied properties. Our own experience suggests 5,[11][12][13] that using different kinds of diamine ligands in the medium with differing surfactants can alter the structural morphology, which in turn allow us to tune their optical and magnetic properties.…”

“…In our earlier work we used CTAB (cetyltrimethylammoniumbromide) surfactant with BD, leading to the formation of 100% cubic morphology, which could be converted to pure hexagonal form by simple addition of manganous ions without any harsh treatment. 12 In the present work, we have attempted to synthesize such nanoparticles with the use of SLS surfactant and the two ligands, i.e. BD and PD, which differ in chain length and are larger than the ED ligand, which was used earlier.…”