Crystal structure and properties of a new magnesium heteropoly-tungstate, Mg7(MgW12O42)(OH)4(H2O)8, and the isostructural compounds of manganese, iron, cobalt and nickel

Robust Polyoxometalate/Nickel Foam Composite Electrodes for Sustained Electrochemical Oxygen Evolution at High pH

“…[25] High-resolution transmission electron microscopy (HRTEM) and fast Fourier transforms (FFT; Figure 2b,i nset) revealed lattice fringes whose dspacings are in line with the (110), (220), and (420) planes of this cubic lattice (Figure 2a)a nd thus support the structural assignment. [25] High-resolution transmission electron microscopy (HRTEM) and fast Fourier transforms (FFT; Figure 2b,i nset) revealed lattice fringes whose dspacings are in line with the (110), (220), and (420) planes of this cubic lattice (Figure 2a)a nd thus support the structural assignment.…”

“…Powder X-ray diffraction (pXRD;F igure 2) of the composite gave signals for the metallic Ni foam and further showed acubic crystal lattice.Literature comparison showed that this cubic crystal lattice corresponds to the well-known Dexter-Silverton POM [M 8 W 12 O 42 (OH) 4 (H 2 O) 8 ]( database no.I CDD-PDF-80-1525). [25] High-resolution transmission electron microscopy (HRTEM) and fast Fourier transforms (FFT; Figure 2b,i nset) revealed lattice fringes whose dspacings are in line with the (110), (220), and (420) planes of this cubic lattice (Figure 2a)a nd thus support the structural assignment. [25] As initial EDX measurements indicated the presence of both Co and Ni ions in the crystal lattice,weused inductively coupled plasma atomic emission spectroscopy (ICP-AES;s ee Table S1 in the Supporting Information) to quantify the Co,N i, and Wc ontent and their ratio.T he analysis was carried out on pure microcrystals which were carefully mechanically removed from the Ni foam.…”

Stabile Polyoxometallat‐Nickelschaum‐Elektroden für elektrochemische Sauerstoffentwicklung im alkalischen Milieu

“…Röntgenpulverdiffraktometrie (pXRD; Abbildung ) des Materials zeigt charakteristische Signale des metallischen Ni‐Schaums sowie eines kubischen Kristallgitters, das dem literaturbekannten Dexter‐Silverton‐POM [M 8 W 12 O 42 (OH) 4 (H 2 O) 8 ] (Datenbanknr. ICDD‐PDF‐80‐1525) zugeordnet werden konnte . Hochauflösende Transmissionselektronenmikroskopie (HR‐TEM) und schnelle Fourier‐Transformation (FFT; Abbildung b, Einschub), zeigten kristalline Bereiche, deren Netzebenen( d) ‐Abstände mit den Miller‐Ebenen (110), (220) und (420) des kubischen Gitters des Dexter‐Silverton‐POM übereinstimmen (Abbildung a) und somit die Strukturzuordnung stützen .…”

“…ICDD‐PDF‐80‐1525) zugeordnet werden konnte . Hochauflösende Transmissionselektronenmikroskopie (HR‐TEM) und schnelle Fourier‐Transformation (FFT; Abbildung b, Einschub), zeigten kristalline Bereiche, deren Netzebenen( d) ‐Abstände mit den Miller‐Ebenen (110), (220) und (420) des kubischen Gitters des Dexter‐Silverton‐POM übereinstimmen (Abbildung a) und somit die Strukturzuordnung stützen . Atomemissionsspektroskopie mit induktiv gekoppeltem Plasma (ICP‐AES; Tabelle S1 der Hintergrundinformationen) an abgetragenen Mikrokristallen ergab ein Co/Ni‐Verhältnis von 6.8:1.2, wodurch sich die Summenformel [Co 6.8 Ni 1.2 W 12 O 42 (OH) 4 (H 2 O) 8 ] (NiCo‐POM) ableiten lässt.…”

Syntheses and X-Ray Crystal Structures of Magnesium- Substituted Polyoxometalates

“…Among the various metals and their derivatives that can be coordinated to the vacant site(s) of lacunary polyoxometalates, magnesium and magnesium derivatives are intriguing because of their efficient properties as catalysts, reagents for organic syntheses, pharmaceutical compounds, and so on [4,5]. However, magnesium-coordinated polyoxometalates (characterized by X-ray crystallography) are still one of the least reported compounds: Examples that have been reported include Mg 8 SiW 9 O 37 ⋅24.5H 2 O [6], Mg 8 SiW 9 O 37 ⋅12H 2 O [6], and Mg 7 (MgW 12 O 42 )(OH) 4 (H 2 O) 8 [7].…”