Silica–[Fe(bpy)3]2+ composite particles with photo-responsive change of color and magnetic property

Formation of composite microspheres comprising a 2,2′-bipyridyl iron(ii/iii) complex and acrylamide by UV irradiation

“…We previously reported on the irreversible dissociation of the tris(2,2'-bipyridyl)iron(II) complex [Fe(II)-bpy] doped into silica sol. 5 We further found the formation of Fe(II)-bpy by UV irradiation (365 ¡ 25 nm) on the mixture of FeCl 3 and bpy with and without the presence of silica sol. 6 Formation of the complex by the processes mentioned above parallels the change in the color and the electron spin states, enabling the preparation of photo-responsive silica microspheres by adding FeCl 3 and bpy to silica sol.…”

Colourimetric solid‐phase extraction coupled with fibre optic reflectance spectroscopy for determination of ascorbic acid in pharmaceutical formulations

“…Amberlite XAD‐16) and Fe(III) was reduced to Fe(II) on the adsorbent surface with reducing action of analyte. The Fe(II) obtained is then able to react with Bpy in order to form a coloured ferroin complex ([Fe(Bpy) 3 ] 2+ )11–13. In fact, Fe(III) complexed with Bpy is a stronger oxidizing agent than Fe 3+ (due to selective stabilization of the ferrous state) and Fe(II)‐Bpy emerging as the product of the redox reaction has a much more intense colour than the corresponding Fe(III)‐complex.…”

Ultraporous Single Phase Iron Oxide−Silica Nanostructured Aerogels from Ferrous Precursors

“…The resulting materials exhibit ultralow density, very large surface area, low refractive index, and low sound velocity . Inside the pores, metal or metal oxide nanophases can be either embedded (mixing particles of the desired phase in the gel) 1,2 or synthesized in situ (using salt precursors of the metal in the gel), conferring multifunctional electronic, magnetic, − optical, , and catalytic properties to the composites.…”