Prussian blue derivative

Galvez, N., Sanchez, P., Dominguez-Vera, J. M. (2005). Preparation of Cu and CuFe Prussian Blue derivative nanoparticles using the apoferritin cavity as nanoreactor. Dalton Trans., 7, 2492—2494. 

Several Prussian blue derivatives with molecular formula (M3[M (CN)6]2i here denoted as [M3M 2]) have been obtained with the aforementioned procedure. The FTIR analysis was obtained with a Bruker Vertex 80 FTIR Spectrometer in the 400 - 4000 cm firequency range. Band stretches of samples as well as the starting materials have been tabulated in Table 1. The asymmetric cyanide stretching of [Fe3Co2] shifts from 2125 to 2168 cm as expected for Prussian blue derivatives (Fig. 1). Similarly, the cyanide band in the 2000 - 2200 cm range also shifts to higher frequencies for the other samples compared to that of [Fe(CN)6] The broad band at aroimd 3500 cm and a sharp small band at 1600 cm confirms the presence of interstitial water molecules inside the cavities. Moreover, the sharp band at 400 - 500 cm is attributed to metal to cyanide bond. 

Y. Guo, A.R. Guadalupe, O. Resto, L.F. Fonseca, and S.Z. Weisz, Chemically derived Prussian blue sol-gel composite thin films. Chem. Mater. 11,135-140 (1999). 

PB and its derivatives are of interest for a variety of reasons, the most important of which is its electrochromism [93]. In addition, it is an electrocatalyst for several different types of substrates, notably hydrogen peroxide, as will be seen below. Synthesis of nanopartides of Prussian Blue is relatively straightforward. It relies on many of the prindples of colloid chemistry, and produces ionically stabilized colloidal solutions (Figure 4.7). As a consequence, the electrochemical behavior of PB N Ps has been examined by several groups. In this section, we discuss the behavior of P B N Ps immobilized at electrodes. 

Not surprisingly, the very interesting and practically useful properties of Prussian blue have resulted in several studies of similar hexacyano derivatives [114] but only a few of them (e.g., ruthenium- and osmium-based systems) have found use in electrochromic devices. More systematic studies should, indeed, be called for in order to harvest the full potential of this group of compounds. 

Prussian blue, in the form of printers inks, artists colors, and paints, soon flooded the market. It also stimulated interest in other potentially useful substances that might be derived from the potash, iron, and animal-residue mixtures. One of these, known as red prussiate of potash, did turn out to be very useful. When combined with ferric ions, it didn t produce a dramatic color until it was exposed to direct sunlight. Then it turned blue. Prussian blue. The discovery revolutionized archi-... 

While bifunctionality is known for the halogens and many pseudohalogens, it is most pronounced for cyanide and influences the structures, properties and chemistry of many of its derivatives. Cyanide bridges were present in the first recorded synthetic inorganic complex, Prussian blue (ca. 1700), and cyanide linkage isomers were often proposed in the old literature but reasonable evidence for the existence of linkage isomers and the structure of Prussian blue is very recent. 

Some of these derivatives, such as Prussian blue, are of considerable commercial importance on account of their characteristic deep colour. As a general rule, the derivatives which are devoid of colour contain iron in one stage of oxidation only within the molecule, whilst the coloured compounds possess divalent and trivalent atoms of iron respectively. It would appear, therefore, that the colour is in some way connected with the presence of similar atoms in more than one stage of oxidation. Thus, ferrous potassium ferrocyanide, Fe"K2[Fe (CN)6], is white, the iron atoms in the positive and negative radicles respectively being divalent. Upon oxidation, however, Prussian blue, Fe K[Fe (CN)e] is obtained, the iron atom of the negative radicle remaining divalent, whilst the positive iron ion is trivalent. 

Properties.—An aqueous solution of sodium nitroprusside deposits Prussian blue on exposure to light. In the presence of alkali sulphides— as, for example, ammonium sulphide—it yields a beautiful purple colour, which is very characteristic, and so sensitive that the presence of 0 0000018 gram of hydrogen sulphide in 0 004 c.c. can easily be detected.2 Ammonium hydroxide does not hinder the colour formation, but caustic alkalies destroy it. It gradually fades on standing, in consequence of oxidation of the sulphide to sulphite. The composition of the purple substance is uncertain, but Hofmann 3 suggests the formula Na3[Fe(CN)5(0 N.SNa)], since, by the action of thio-urea, CS(NH2)2, upon sodium nitroprusside, he obtained the complex derivative Na3[Fe(CN)5(0 N.SCNH.NH2)], as a carmine-red powder, closely similar to the substance under discussion.4... 

Iron and Cyanogen—Ferrous Cyanide—Constitution of Ferro- and Fern-cyanides —Ferrocyamdes—Cuproferrocyanides—Double Salts with Mercunc Cyanide —Ferricyamdes—Iron Derivatives of Ferro- and Ferri-cyanides—Prussian Blue. 

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