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Cellulose disassembly is an important issue in designing nanostructures using cellulose-based materials. In this work, we present a combination of experimental and theoretical study addressing the disassembly of cellulose nanofibrils. Through 2,2,6,6-tetramethylpiperidine-1-oxyl-mediated oxidation processes, combined with atomic force microscopy results, we show the formation of nanofibers with diameters corresponding to that of a single-cellulose polymer chain. The formation of these polymer chains is controlled by repulsive electrostatic interactions between the oxidized chains. Further, first-principles calculations have been performed in order to provide an atomistic understanding of the cellulose disassembling processes, focusing on the balance between the interchain (IC) and intersheet (IS) interactions upon oxidation. First, we analyze these interactions in pristine systems, where we found the IS interaction to be stronger than the IC interaction. In the oxidized systems, we have considered the formation of (charged) carboxylate groups along the inner sites of elementary fibrils. We show a net charge concentration on the carboxylate groups, supporting the emergence of repulsive electrostatic interactions between the cellulose nanofibers. Indeed, our total energy results show that the weakening of the binding strength between the fibrils is proportional to the concentration and net charge density of the carboxylate group. Moreover, by comparing the IC and IS binding energies, we found that most of the disassembly processes should take place by breaking the IC O–H···O hydrogen bond interactions and thus supporting the experimental observation of single- and double-cellulose polymer chains.

We report a novel combination of nanomaterial proposed as a peroxidase‐like enzymatic mimic for detection of H2O2, where CeO2 nanoparticles dispersed on SBA‐15 through synthesis by the impregnation‐decomposition cycles method (IDC). The system displays a good peroxidase‐like activity and catalyzes to the oxidation of 3,3',5,5‘‐tetramethylbenzidine (TMB) by H2O2. KM values were calculated between 0.04 and 0.08 mM for different (CeO2/SBA‐15)x catalyst system, the results demonstrates that the combination of these materials displayed a good affinity to TMB substrate, consequently improving the colorimetric assay, due to uniform mesostructures of SBA‐15 and their high surface areas. A detailed study of synergistic effects between CeO2NPs and SBA‐15 support were held in order to understand how these effects can improve the colorimetric assay. Additionally, high resolution transmission electron microscopy (HR‐TEM), energy dispersive X‐ray spectroscopy (EDX), Raman spectroscopy, thermogravimetric analysis (TGA), small angle X‐ray scattering (SAXS) and textural properties were utilized for characterization of the prepared catalysts systems.