XRD pattern indicates presence of small amounts of aFe2O3 in all the three samples whose percentage first decreases and then increases with milling time. Since milling was carried out in a wet medium of toluene, unlike as the case of dry milling, here the chance to recombine some unreacted salts to yield a substantial amount of zinc ferrite exists and hence is the overall reduction of hematite in the initial stage of milling. Hence during first stage of milling, may be some unreacted ferric and zinc salts and the aFe2O3 present will react to form ZnFe2O4 and thereby aFe2O3 line gets less intense during 30 minutes milling. But during prolonged milling, due to nanometer sized grains, high local pressures and temperatures during collisions with balls and vial, and the subsequent kinetic energy produced will lead to a decomposition of ZnFe2O4 in the milling process. There are reports of production of Fe3O4 (by product of aFe2O3) as a result of prolonged milling. But in our present study no traces of Fe3O4 was detected by XRD.
An interesting feature is that for wet milling, we have employed a low rpm of 360 comparing with that of dry milling where the rpm was 650. But careful analysis of XRD patterns shows a speedy decomposition of zinc ferrite to zinc oxide and hematite in toluene based wet milling. From figure, it is evident that to emerge 100 line of zinc oxide only 5 hours wet milling is sufficient whereas in dry milling, it took 10 hours to get an observable 100 zinc oxide plane.
As in the case of dry milling, here also broad shape of the diffraction peaks replicates the formation of fine particle structure with small crystallite size distribution and existence of strong internal lattice strains which is introduced during high energy ball milling. Average size of the particle, which is calculated by Debye Scherer formula, and plotted against the milling time. Here also there is no sudden reduction which is similar to the results obtained for dry milled samples.
Lattice parameter reduction and the lattice strain calculated are in tune with the results obtained for dry milled zinc ferrite.
An interesting feature is that for wet milling, we have employed a low rpm of 360 comparing with that of dry milling where the rpm was 650. But careful analysis of XRD patterns shows a speedy decomposition of zinc ferrite to zinc oxide and hematite in toluene based wet milling. From figure, it is evident that to emerge 100 line of zinc oxide only 5 hours wet milling is sufficient whereas in dry milling, it took 10 hours to get an observable 100 zinc oxide plane.
As in the case of dry milling, here also broad shape of the diffraction peaks replicates the formation of fine particle structure with small crystallite size distribution and existence of strong internal lattice strains which is introduced during high energy ball milling. Average size of the particle, which is calculated by Debye Scherer formula, and plotted against the milling time. Here also there is no sudden reduction which is similar to the results obtained for dry milled samples.
Lattice parameter reduction and the lattice strain calculated are in tune with the results obtained for dry milled zinc ferrite.
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