## 3 Results and Discussion
### Synthesis and Characterization
The magnetic composites were characterized by X-ray diffraction (Figure 5). The XRD patterns (Figure 5) of the chrysotile impregnated with iron after the CVD process showed typical reflections of forsterite phase, Mg\({}_{2}\)SiO\({}_{4}\), which is a magnesium silicate resulting from heat treatment of chrysotile [20]. The XRD patterns also showed the presence of typical reflections of carbide phase, Fe\({}_{3}\)C, and iron metal. The graphitic carbon phase is only observed for the material with 25 %wt iron (Fe25%). Figure 4: Raman spectra of magnetic amphiphilic nanoparticles Fe1% and Fe25%. Figure 5: XRD patterns for Cris, Fe1% and Fe25%. The iron phases present in the magnetic amphiphilic material based on chrysotile were confirmed by M\(\,\)ossbauer spectroscopy (Figure 6). Figure 7 shows a plot of distribution of the iron phases for Fe1% and Fe25%. M\(\,\)ossbauer spectrum of amphiphilic material Fe1% (Figure 6) showed the presence of a sextet related of metallic iron (\(\delta\) = 0 mm s\({}^{-1}\), \(\Delta\) = 0 mm s\({}^{-1}\), B\({}_{\rm HF}\) = 33 T) with relative area of 21%, and signals related to the reduced iron oxide, magnetite Fe\({}_{3}\)O\({}_{4}\), (\(\delta\) = 0.66 and 0.23 mm s\({}^{-1}\), \(\Delta\) = 0.02 mm s\({}^{-1}\), B\({}_{\rm HF}\) = 46.2 and 48.2 T) with relative area of 8% and finally iron carbide (\(\delta\) = 0.16 mm s\({}^{-1}\), \(\Delta\) = \(-\)0.02 mm s\({}^{-1}\), B\({}_{\rm HF}\) = 20.6 T) with relative area of 12%, formed during the CVD process. Fe1%  
Figure 6: M\(\,\)ossbauer spectra at room temperature of magnetic amphiphilic nanoparticles Fe1% and Fe25%. \[\mathrm{Fe_{2}O_{3}\to Fe_{3}O_{4}\to FeO\to Fe^{0}} \tag{1}\]0 M\(\,\)ossbauer iron phases distribution of Fe1% and Fe25%. also shows the presence of Fe\({}^{3+}\) and Fe\({}^{2+}\) in two different phases. The Fe\({}^{3+}\) (\(\delta\) = 0.37, \(\Delta\) = 0.84 mm s\({}^{-1}\) and relative area 22%) can be associated to the replacement of Si\({}^{4+}\) in the structure of chrysotile and hence forsterite. The presence of Fe\({}^{2+}\), (\(\delta\) = 1.14 and 0.89 mm s\({}^{-1}\), \(\Delta\) = 2.90 and 0.89 mm s\({}^{-1}\)) with relative area of 37% can be associated with ferrous ions that replaced the magnesium in some positions of forsterite [21, 22]. In these phase, Mg\({}^{2+}\) and Fe\({}^{2+}\) can consequently take two octahedral sites in the crystal lattice structure of these mineral. For the M\(\,\)ossbauer spectrum amphiphilic material Fe25% also it is possible to observe the presence of metallic iron with relative area of 23% (\(\delta\) = 0 mm s\({}^{-1}\), \(\Delta\) = 0 mm s\({}^{-1}\), B\({}_{\rm HF}\) = 33 T) and the absence of the magnetite phase. The magnetite is likely reduced by H\({}_{2}\) and carbon formed in large amounts in the sample Fe25% during the CVD process according to Equation (1). The CVD process led to the formation of large amounts (38%) of iron carbide (\(\delta\) = 0.16 mm s\({}^{-1}\), \(\Delta\) = \(-\)0.02 mm s\({}^{-1}\), B\({}_{\rm HF}\) = 20.6 T). An important feature of the composites Fe1% and Fe25% is the strong magnetic behavior probably related to the presence of Fe\({}^{0}\), Fe\({}_{3}\)O\({}_{4}\), and iron carbide (Fe\({}_{3}\)C) [23]. The presence of these magnetic phases is very interesting for the applications of these materials. In fact, the chrysotile impregnated with iron after CVD process has high values of magnetization. Figure 8 and Table 1 show the hysteresis loops and the main magnetic parameters for the samples Fe1% and Fe25%. It can be observed that the saturation magnetization (M\({}_{\rm s}\)) is larger for the sample with more Fe content, in agreement with the results obtained from M\(\,\)ossbauer spectra, where it shows that sample Fe25% has a larger contribution of alpha-Fe and Fe carbide. The low remanence values result in a small squareness ratio(S), being 8 and 10% for samples Fe1% and Fe25%, respectively. A value of S less than 25% indicates that a certain population of the particles is in a superparamagnetic state at the temperature of measurement.