| Comparing with the bulk semiconductor, nanometer scale semiconductors especially some different shaped nanometer scale semiconductors show many good properties which normal materials don't have. Those properties have attracted many scientists' interest. ZnS is the wide band gap semiconductor. It has perfect luminescent property. There are thousands of literatures about it in past ten years. ZnS hollow sphere has been synthesized by many methods recently. But the properties of luminescent and under high pressure have not been studied. By using diamond anvil cell and synchrotron radiation source the in situ energy dispersive X-ray diffraction(EDXD) measurements on nano ZnS hollow sphere have been carried out. The luminescent properties of nano ZnS hollow sphere which were treated with hydrostatic pressure and un-hydrostatic pressureIn situ EDXD measurements on nano ZnS hollow sphere have been carried out by using diamond anvil cell with synchrotron radiation. The EDXD pattern of nano ZnS hollow sphere under atmospheric pressure shows that there are two structures of ZnS in the nano ZnS hollow sphere. They are wurtzite and zinc blende ZnS. In high pressure processing, the wurtzite structure ZnS transform to zinc blende structure ZnS as the pressure is up to 11.2 GPa. And, there is a phase transition from zinc blende structure to rocksalt structure when the pressure is up to 16.0 GPa. This phase transition pressure is the same as the normal nanocrystalline zinc sulfide which was reported in many literatures before. An unknown diffraction peak appeared at about 18.3 KeV as the pressure reach 26.8 GPa. This peak can not be found in the same studies of other groups. There are three probabilities of the appear of this unknown peak in our analysis. Firstly, there are two structures of ZnS in the sample at the same time as the pressure reach 26.8 GPa, zinc blende structure and rocksalt structure, there must be some interface between these two structures, and the distance of this interface shoud be constant, this pead may be the diffraction pead of the interface distance. Secondly, the cinnabar structure of ZnS was concluded by many theory calculations, but this structure has not been found in experimental study, and the theory studies did not give the crystal constant, there is probability that the peak is one of the diffraction peaks of the cinnabar structure of ZnS. Lastly, the peak may be the sudden noise of the equipment system.The photo luminescence (PL) spectrum was measured by JOBIN YVON HORIBAC Raman spectrograph excitated by the laser of He-Cd that weavelength is 325nm. Three samples were measured, the raw nano ZnS hollow sphere, the ZnS that had been treat with 33.6 GPa hydrostatic pressure and 30.0GPa un-hydrostatic pressure respectively. There many difference among the three photo luminescence spectrums. The PL of raw nano ZnS hollow sphere become broaden but has not shift Compare to the PL spectrum of normal bulk ZnS. However, the second sample's PL spectrum become broaden and has a shift to high frequency, but the peak of low frequence vanished. Further more, the third sample's PL spectrum has two peaks and a shift to high frequency at the same time. With comparing the TEM photos of the same three samples, we find the fact that cause the differences of the PL spectrum of the samples. Nanometer scale is the importan fact which lead to the broadening of the PL spectrum. And it can also cause the shift of the PL spectrum to high frequence band. But the interface effec cause the PL spectrum shift to low frequency band. The shift of the luminescence spectrum is decided by the two facts at the same time. Further more, the appearance of the surface effect can lead the low frequency peak of the PL spectrum of ZnS vanish away or to be weaken. In a summary, our investigations of the structure phase transition of nano ZnS hollow sphere and PL spectrum of the sample after being treated with different high pressure are basal research. It make us know the structure and PL characters clear...
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