High Bulk Modulus of Nanocrystal γ-Fe₂O₃with Chemical Dodecyl Benzene Sulfonic Decoration Under High Pressure

Abstract

Structural transformation in y-Fezo3 nanocrystals (about IOnm) with dodecyl benzene sulfonic (DBS) coated is studied by using high-pressure energy dispersive x-ray diffraction o f synchrotron radiation and high-resolution transmission electron microscopy (HRTEM). Relative to the bulk crystal, the transition pressure showed a decrease while the compressibility increases significantly up to 375 (A9 GPa). HRTEM picture confirmed that there is surface cladding surrounding nanocrystals due to DBS, which formed new special boundaries between nanocrystals and should be different from the ordinary grain boundaries. The experimental results imply that the surface layers of y-Fe& nanocrystals have strong effect on the compressibility.

Study of Nanomaterials under High Pressure

“…The results ob- tained are in good agreement with the available experimental data [14][15][16][17][18] as compared with the other EOSs such as Vinet's [20]. Very significant agreement has been observed in the low pressure values.…”

“…It should also be understood that all equations of state discussed in this work (Murnaghan and Vinet) have matched with the experimental data. There was a good agreement between the theoretical values of V/V 0 as a function of P, obtained from Equation (7) as has been found with the corre 0 nm), and -Al 2 O 3 (37 nm) nanomaterials [14][15][16][17][18]. It may be concluded from the above discussion that the EoS obtained in this work [Equation (7)], in general, can produce much better pressure dependent volume expansion data, as compared to other equations of state, for a wide range o nanomaterials.…”

“…The input data required are given in Table 1. The results obtained are reported in Figures 1-20 along with the available experimental data [14][15][16][17][18] for the sake of comparison. It is found tha od agreement with the experimental data.…”

“…Therefore, investigation of the behavior of nano-sized materials under high pressure is indispensable, especially due to the immense potential of applications associated with these materials. Several experiments have been performed to study and explain the behavior of nonmaterial [7][8][9][10][12][13][14][15][16][17][18]. It is then not surprising that high-pressure investigations of nanomaterials develop in parallel to the growth of nanoscience either for better understanding of the properties of nanomaterials or providing alternative methods for nanostructuration.…”

“…It is then not surprising that high-pressure investigations of nanomaterials develop in parallel to the growth of nanoscience either for better understanding of the properties of nanomaterials or providing alternative methods for nanostructuration. Experimental data [7][8][9][10][12][13][14][15][16][17][18] used by different techniques such as X-Ray diffraction under hydrostatic pressure in a diamond anvil cell (DAC) method are obtained, using high energy Synchrotron radiation and Raman spectroscopic technique, High pressure X-Ray diffraction and X-Ray absorption, Neutron diffraction studies of compressibility method, Synchrotron X-Ray diffraction method and Laser induced vapour phase reaction.…”