Application of Heteropolyacid H4SiMo3W9O40 for the Preparation of Bimetallic MoWS2/Al2O3 Hydrotreatment Catalysts

Photosynthesis of urea from N2 and CO2 using dual active site SiW6Mo6@MIL-101(Cr) at room temperature

“…The Keggintype SiW 12−X Mo X (X = 3, 6, and 9) were prepared at the Si/W/ Mo ratio of 1 : (12 − X) : X (X = 3, 6, 9), according to the previous literature method. 29,30 For example, H 4 SiW 6 Mo 6 was prepared as follows: Na 2 SiO 3 (1 mmol), Na 2 WO 4 (6 mmol) and Na 2 MoO 4 (6 mmol) were suspended in 50 mL H 2 O at 110 °C. Aqueous 6 M HCl (18 mmol) was added drop-wise to the mixture and stirred for 2 h. Aer cooling to room temperature, 20 mL ethyl ether and an appropriate amount of sulfuric acid were added to the solution, which formed a chartreuse etherate.…”

“…The Keggin-type SiWMo and composites (SiW 12−X Mo X @MIL-101(Cr) (X = 0, 3, 6, 9, 12)) with the host and guest structure were obtained by the process 29,30 shown in Scheme 1 (see synthesis details in the experimental section). The effect of the composites on the photocatalytic nitrogen/carbon reduction reactivity was studied by adjusting the ratio of W to Mo in the POMs.…”

Bulk hydrotreating MonW12-nS2 catalysts based on SiMonW12-n heteropolyacids prepared by alumina elimination method

“…A series of bulk MonW12-nS2 hydrotreating catalysts was synthesized by HF etching of alumina from MonW12-n/Al2O3 catalysts. First, supported samples were prepared by the incipient wetness method via impregnation of -Al2O3 extrudates with aqueous solutions of H4SiMonW12-nO40 HPAs [4,[9][10][11]. These mixed HPAs are derived from the Keggin-type polyoxometallate H4SiW12O40, consisting of a regular SiO4 tetrahedron surrounded by 12 WO6 octaedra, which are connected by shared edges to form trimetallic W3O13 groups joined together by their vertices.…”

“…The use of Ni(Co)MoWS systems, in which both tungsten and molybdenum atoms are simultaneously present, allowed increasing HDS and HYD activities [1][2][3][7][8][9][10]. Thomazeau et al [2] reported that the formation of mixed MoWS2 crystallites is possible only from a precursor which contains both closely related metals in the structure at once.…”