# Influence of Synthesis Parameters in Obtaining KIT-6 Mesoporous Material
## 3 Results and Discussions  
Figure 2 shows the low-angle diffractograms of all the synthetized samples. The samples in Figure 2A show reflection characteristics of materials with KIT-6 type, displaying (211), (220) and (332) Miller indices that are characteristic of three-dimensional mesoporous structures with spatial group _la3d_, typical of structures organized in cubic array [9; 26; 27]. The samples K0.022, KDT2, KMT, KEt, KYP and KAT12 in Figure 2B show reflections with (100), (110) and (120) Miller indices. According to [PERSON] et al. [28], these reflections are characteristic of two-dimensional mesoporous structures with spatial group _P6 mm_, typical of structures organized in a hexagonal array, corresponding to SBA-15 type materials. The samples KAT6 and K Pe in Figure 2B not show any arranged structure. Based on the data of the modification in the molar proportion of the organic template, two different behaviors can be noticed. The sample synthetized with a lower quantity of template (K0.012 sample) showed similar results to the standard KIT-6. This demonstrates that, even with the reduction employed in the synthesis, there was no interference in the critical micellar concentration (CMC) and subsequent formation of 3D cubic structure desired. A different behavior was observed with regard to the sample with a higher than standard molar proportion (K0.022 sample). The formation of a 2D hexagonal structure was noticed, referent to the SBA-15 mesoporous material. According to [PERSON] et al. [29], the increase in the quantity of the template used in the synthesis at constant temperature can lead to a transition in the cubic phase to the hexagonal phase, as can be observed in the present study. Figure 3A shows a representative scheme of the data obtained in this modification stage. For the modification performed at the dissolution time of the organic template, it is noticeable that, by reducing the standard time from 6 h to 2 h, a cubic _la3d_ structure is not obtained. However, for this reduction time a SBA-15 material with high _P6 mm_ hexagonal organization is obtained. This behavior can be related to the micellar formation and posterior protonation of the EO (ethylene oxide) groups in the early synthesis stage. The short period of 2 h, possibly, is not enough for the interaction of the micelles with the inorganic phase of silica, thus favoring the formation of a two-dimensional structure, which is thermodynamically more favorable than a three-dimensional one. For all the samples with  
Figure 2: X-ray diffraction (XRD) patterns of all synthesized samples. times higher than 2 h, the formation of cubic structure-like KIT-6 material was observed (Figure 3B). However, when observing the XRD peaks of the KDT4 sample, a displacement to a higher value of 20/angle in comparison to the KIT-6 standard was noted. This behavior demonstrates an interference in the structural organization of the material. Such results determine that the required time to the dissolution of the P123 template directly influences the formation and structural organization in the synthesis of the KIT-6 material. The modifications made in the type of alcohol employed in the standard synthesis showed significant data regarding the study of the synthesis mechanism of ordered mesoporous material. It was possible to observe that all alcohols with carbonic chains shorter than butanol (Kmt, KEt and KPr samples) exhibited a structure of SBA-15 type, while the alcohol with the higher carbonic chain, 1-pentanol (sample KPe), did not display any ordered structure. In a study developed by [PERSON] et al. [30], the authors proposed that butanol interacts with the chains of PEO (polyethylene oxide) and PPO (polypropylene oxide) of the P123 micelles behaving as a type of co-template. Thus, the butanol alcohol acts directly on the curvature of the bi-continuous channels and is responsible for forming the cubic structure of the KIT-6 material.