Synthesis and morphological characterization of nanocomposite based on anodic TiO2 nanotubes and poly(N-maleoyl Glycine-CO-Acrylic acid)

Indexación: Scopus.In this study, we examined the synthesis, and characterization of TiO2/poly(N-maleoylglycine-co-acrylic acid) (TiO2/poly(MG-co-AA)) nanocomposite. The nanocomposite was prepared by the dispersion of TiO2 nanotubes in a water solution of the polymer (3% w/w) and then it was lyophilized. The nanocomposite was characterized by FTIR and Raman spectroscopies. The incorporation of TiO2 nanotubes to the polymeric matrix was determined by transmission electron microscopy (TEM) from which TiO2 nanotubes in the inner of copolymer with diameters ranging between 90 and 100 nm were observed. The overall morphology of the previously synthetized nanotubes was determined by scanning electron microscopy (SEM). For the nanocomposite system, the morphology was studied by atomic force microscopy (AFM) from which a grain shape structure was observed. This process resulted in a new nanocompsite material with an average grain diameter estimated by SEM and AFM ranging between 210-240 nm. It was observed that the nanotubes were homogeneously dispersed within the polymeric matrix. The prepared material could be suitable in the design of electronic devices and additionally could have potential applications as biomaterial.https://scielo.conicyt.cl/pdf/jcchems/v62n3/0717-9324-jcchems-62-03-3634.pd

β-cyclodextrin and adamantane polyacrylic acid copolymers as supramolecular binder for silicon anodes: N-methylpyrrolidone or water for preparing the slurries?

Silicon is a promising material for anodes in future generations of LIBs. However, its volume changes during the lithiation/delithiation process that degrades battery performance, making it an impractical alternative. To mitigate this issue, we have found a viable alternate solution, which is the preparation of adamantane-polyacrylic acid (AdEN-AA) and β-cyclodextrin-polyacrylic acid (βCD6A-AA) polymers as supramolecular binders. The advantage of these binders is that polymers leverage host-guest interactions. To carry out this research, we prepared the anode materials in water and in NMP, and then we studied their capacity to crosslink and gel. Additionally, we examined the extent of the supramolecular interaction vs. hydrogen bond. Thermogravimetric analysis showed that the thermal stability of the mixture of complementary polymer increased in the following order: AdEN-AA/βCD6A-AA in NMP < βCD6A-AA/PAA < AdEN-AA/βCD6A-AA, with the latter two in water. Accordingly, the anode material prepared in water shows the highest stability, retaining capacities of over 1000 mAhg-1 after 90 cycles vs. 279 mAhg-1 of the electrode prepared in NMP. The results agreed with the SEM micrographs of the anode material, in which the slurry prepared in water showed better integrity of the silicon nanoparticles and of solid electrolyte interphase than the slurry prepared in NMP