Nanostructured VOx/VO(PO4)n Using Solid-State Vanadium Containing Phosphazene Precursors: A Useful Potential Bi-Catalyst System

Journal of Nanomaterials

Barrera

Segovia

et al. 2015

A systematic study of the synthesis of V2O5nanostructured materials using macromolecular PS-co-4-PVP·(VCl3)yand chitosan·(VCl3)ycomplexes is presented. It is demonstrated that various coordination degrees of the metal into the polymeric chain specifically influence the product formation after pyrolysis. PS-co-4-PVP·(VCl3)yand chitosan·(VCl3)ycomplexes were prepared by simple coordination reaction of VCl3with the respective polymer in molar ratios 1 : 1, 1 : 5, and 1 : 10 metal/polymer and characterized by elemental analysis, IR spectroscopy, and TGA/DSC analysis. Solid-state thermolysis of these precursors at several temperatures under air results in nanostructured V2O5using all precursors. The size and shape of the nanostructured V2O5depend on the nature of the polymer. For the chitosan·(VCl3)yprecursors sub-10 nm nanocrystals are formed. The calcination process, involved in the preparation method, produces V2O5with photoluminescence in the visible light region, suggesting the possible application in oxygen sensing devices.

Section: Introductionmentioning

confidence: 99%

Crystallizing Vanadium Pentoxide Nanostructures in the Solid‐State Using Modified Block Copolymer and Chitosan Complexes

Journal of Nanomaterials

Barrera

Segovia

et al. 2015

“…Chitosan induces the formation of smaller nanoparticles (6 nm) for the 1:1 molar ratio than for 1:5 ratios. Unlike to the previously reported other solid state method [53][54][55][56][57][58][59][60] which start from precursor contained phosphazene derivatives linked to metal and organometallic fragments the here reported method allow the formation of phase pure metal oxides.…”

Section: Discussionmentioning

confidence: 84%

Solid State Morphology and Size Tuning of Nanostructured Platinum Using Macromolecular Complexes

Valenzuela

Baez

et al. 2015

J. Chil. Chem. Soc.

Self Cite

The macromolecular complexes Chitosan•(PtCl 2 ) n and PSP-co-4-PVP•(PtCl 2 ) n , were prepared from the respective polymer and PtCl 2 in metal:polymer molar ratios 1:1 and 1:5. Pyrolisis of the macromolecular complexes Chitosan•(PtCl 2 ) n and PSP-co-4-PVP•(PtCl 2 ) n at 800 °C under air affords cubic nanostructured Pt in the pure phase. The morphology of the pyrolityc products depends on the molar metal:polymer ratio; i.e. a "cotton" 3D shape for the 1:1 ratio and a "foamy" 3D shape for the 1:5 ratio. On the other hand, the particle size depends on the polymer nature, obtaining Pt nanoparticles as small as 6 nm for the chitosan precursors in both molar ratio.

“…The smallest nanoparticles were obtained for the chitosan precursor in a 1:5 ratio (see Figure 4), where nanoparticles as small as 8 nm were observed. Although several solution methods to prepare nanoparticles of V 2 O 5 [69][70][71] have been described, only a few solid-state methods have been reported [73][74][75]. For example, solid-state thermal decomposition of [NH 4 V 3 (OH) 6 (SO 4 ) 2 ] affords single-crystalline V 2 O 5 nanoparticles, used as cathode material for lithium-ion batteries [73].…”

Section: Vanadiummentioning

confidence: 99%

“…For example, solid-state thermal decomposition of [NH 4 V 3 (OH) 6 (SO 4 ) 2 ] affords single-crystalline V 2 O 5 nanoparticles, used as cathode material for lithium-ion batteries [73]. In addition, pyrolysis of the solid [N 3 P 3 (OC 6 H 5 ) 5 (OC 5 H 4 N•Cp 2 VCl][PF 6 ] affords mixtures of V 2 O 5 /VO(PO 3 ) 2 [74].…”

Section: Vanadiummentioning

confidence: 99%

Solid-State Preparation of Metal and Metal Oxides Nanostructures and Their Application in Environmental Remediation

Valenzuela

Laguna‐Bercero

2022

IJMS

Nanomaterials have attracted much attention over the last decades due to their very different properties compared to those of bulk equivalents, such as a large surface-to-volume ratio, the size-dependent optical, physical, and magnetic properties. A number of solution fabrication methods have been developed for the synthesis of metal and metal oxides nanoparticles, but few solid-state methods have been reported. The application of nanostructured materials to electronic solid-state devices or to high-temperature technology requires, however, adequate solid-state methods for obtaining nanostructured materials. In this review, we discuss some of the main current methods of obtaining nanomaterials in solid state, and also we summarize the obtaining of nanomaterials using a new general method in solid state. This new solid-state method to prepare metals and metallic oxides nanostructures start with the preparation of the macromolecular complexes chitosan·Xn and PS-co-4-PVP·MXn as precursors (X = anion accompanying the cationic metal, n = is the subscript, which indicates the number of anions in the formula of the metal salt and PS-co-4-PVP = poly(styrene-co-4-vinylpyridine)). Then, the solid-state pyrolysis under air and at 800 °C affords nanoparticles of M°, MxOy depending on the nature of the metal. Metallic nanoparticles are obtained for noble metals such as Au, while the respective metal oxide is obtained for transition, representative, and lanthanide metals. Size and morphology depend on the nature of the polymer as well as on the spacing of the metals within the polymeric chain. Noticeably in the case of TiO2, anatase or rutile phases can be tuned by the nature of the Ti salts coordinated in the macromolecular polymer. A mechanism for the formation of nanoparticles is outlined on the basis of TG/DSC data. Some applications such as photocatalytic degradation of methylene by different metal oxides obtained by the presented solid-state method are also described. A brief review of the main solid-state methods to prepare nanoparticles is also outlined in the introduction. Some challenges to further development of these materials and methods are finally discussed.