A2B6 NANOCRYSTALS DOPED WITH MAGNETIC IMPURITIES (REVIEW)

The special properties of transition-metal-doped А2В6 nanostructures have opened up new opportunities for their use in electronics and optoelectronics, in solar cells, for the manufacture of short-wave light-emitting and laser diodes, and the resulting pronounced ferromagnetism at room temperature allows them to be used in spintronics devices. In addition, pure and doped ZnO nanocrystals, due to their non-toxicity, are used in biosensors, drug delivery and other biological applications. It is known that solar cells sensitized by quantum dots have attracted much attention because of their promising prospects for improving the power conversion efficiency. Thus Zn-Cu-In-Se QDSCs maintain a record (PCE) of 12.98%. But the advantages of CdTe QDSCs are high extinction coefficient (105 cm-1 ) and ease of synthesis. In addition, CdTe has a narrower forbidden zone (1.5 eV), which extends the light absorption range to the longer wavelength region, and the higher edge of the conduction band accelerates the injection of electrons from CdTe CTs into the photoanode. Dilute magnetic semiconductors (DMS) combine promising electrical and ferromagnetic properties (FP) with optical transparency, thermal and radiation resistance in terms of practical applications. For use in spintronics, DMS can be obtained by adding magnetic impurities (Co, Ni, Gd, Sm, Eu, Ce, and Er) to the nodes of the original lattice of А2В6 nanocrystals. The main requirements for DMS are the presence of FP at room temperature and high values of specific magnetization of samples in the saturation state. In this review, various synthesis methods of doped ZnO:Mn, CdTe:Mn/Co, CdS:Mn/Cr/Fe/Al, CdTe/ZnS:Mn nanocrystals are considered. Also, the methods of studying the structure and properties of these materials are considered, namely: X-ray diffraction studies, photoluminescence, absorption and EPR spectra. The magnetic properties of doped А2В6 nanocrystals are also discussed. Finally, attention is paid to the practical application of А2В6 nanostructures.