Thin (single–triple) niobium oxide layers on mesoporous silica substrate

Recent progress in block copolymer soft-template-assisted synthesis of versatile mesoporous materials for energy storage systems

“…155 The versatile so-template processes enabled the synthesis of various mesoporous metal oxides in single and multiple compositions, as well as nanoparticle-decorated metal oxides. 101,[174][175][176][177][178][179][180][181][182] Recently, Yang et al reported the synthesis of multi-composition and nanoparticle-decorated mesoporous metal oxides (Fig. 6f).…”

Enhanced NiO Dispersion on a High Surface Area Pillared Heterostructure Covered by Niobium Leads to Optimal Behaviour in the Oxidative Dehydrogenation of Ethane

“…[35] According to the structural and spectroscopic analysis of supports, this shift to higher energy band-gaps in Nb-containing PCH materials can be ascribed to the presence of well-anchored Nb 5+ sites, rather than to the formation of Nb2O5. [36] This improved dispersion of Nb 5+ would be responsible for the hindered sinterization towards Nb2O5. These findings are in agreement with the characterization results reported by Kondo and coworkers, [36] who found a similar effect on NbOx-SBA-15 system, in which the authors were able to control the growth of monobi-and tri-layered niobium oxide on the surface of the mesoporous silica, without Nb2O5 formation.…”

“…[36] This improved dispersion of Nb 5+ would be responsible for the hindered sinterization towards Nb2O5. These findings are in agreement with the characterization results reported by Kondo and coworkers, [36] who found a similar effect on NbOx-SBA-15 system, in which the authors were able to control the growth of monobi-and tri-layered niobium oxide on the surface of the mesoporous silica, without Nb2O5 formation. The analyses of the supports by TEM and EDX show the homogeneous distribution of Nb on the porous support (Fig.…”

“…This effect goes in line with our previous statements, by which an effective interaction between Nb 5+ and PCH support gives rise to dispersed Nb 5+ sites, displaying a different chemical nature than those Nb entities found in Nb2O5. [36]…”

“…At relatively low Nb concentration on the support (5 and 15 % Nb), the samples display a single Nb 3d5/2 XPS peak centred at 207.9 eV, which can be assigned to anchored Nb 5+ species (Figure 8, spectra a and b, respectively). [36] When increasing the amount of Nb incorporated on siliceous porous clays heterostructures, a new peak at lower binding energies (ca. 206.5 eV) appears in the spectra (Figure 8, spectra c), which can be assigned to Nb 5+ in Nb2O5.…”