Synthesis and catalytic application of PVP-coated Ru nanoparticles embedded in a porous metal–organic framework

Abstract

A hybrid catalyst consisting of polymer-coated Ru nanoparticles (Ru-PVP, PVP: poly(N-vinyl-2-pyrrolidone)) embedded in a porous metal-organic framework of ZIF-8 (Ru-PVP@ZIF-8) was synthesized by the crystallization of ZIF-8 in a methanol solution of Ru-PVP. The structural properties of Ru-PVP@ZIF-8 were examined by N2 gas adsorption, infrared spectra, and X-ray powder diffraction measurements. We successfully identified the most appropriate pretreatment conditions for surface activation of the Ru nanoparticles in the catalyst. The pretreated Ru-PVP@ZIF-8 was applied for a CO oxidation reaction with H2 gas feeds. Ru-PVP@ZIF-8 was found to exhibit higher catalytic activities and higher CO2 selectivity than those observed on a carbon-supported Ru-PVP (Ru-PVP/C), implying that the pores of the ZIF-8 provide a more suitable environment for the reaction with O2 and CO gases.

Controlled colloidal metal nanoparticles and nanoclusters: recent applications as cocatalysts for improving photocatalytic water-splitting activity

“…3 Since the 1980s, the research on metal colloids has progressed substantially and the expression "metal NPs" has been coined. [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23] In the last two decades, research on metal NPs has increased explosively, and the techniques to synthesize metal NPs have advanced dramatically. In recent years, it has become possible to control not only the size of metal NPs but also their geometrical structure.…”

Anisotropic Growth of Silver Nanoparticles Is Kinetically Controlled by Polyvinylpyrrolidone Binding

“…For synthetic approaches that do not utilize direct deposition on substrates, capping agents such as halogens, , citrate, − and polymers − are used to stabilize the NPs against aggregation. These capping agents are thought to serve a dual role during synthesis, acting not only as a stabilizing agent but also as structure-directing agents (SDA), since their addition often influences the shape of the NPs. ,,,− Among polymers, poly­(vinylpyrrolidone) (PVP) is widely used for the synthesis of coinage metal NPs (Ag, Au, Cu), to produce different shapes including cubes, ,,,, octahedra, ,,, prisms, − and wires. ,, PVP is also prevalently used for the synthesis of many other metal NPs, such as Pd, Pt, and Ru …”

“…21,31,32 PVP is also prevalently used for the synthesis of many other metal NPs, such as Pd, 33 Pt, 34 and Ru. 35 Xia's group has published extensively on Ag NP synthesis in the presence of PVP. 7,14,15,22,36−55 In 2002, his group employed a polyol method for the shape-controlled synthesis of Ag nanocubes 38 and Ag nanowires, 37 in which the solvent ethylene glycol reduced AgNO 3 in the presence of PVP under controlled reaction conditions.…”

Chemoselective Hydrogenation of Crotonaldehyde Catalyzed by an Au@ZIF‐8 Composite

“…The second strategy has proven increasingly popular because it allows for independent control (precontrol) over particle size and because it typically yields pinhole‐free MOF coatings—thereby ensuring that gas‐ or solution‐phase molecules must traverse the MOF to reach a potentially catalytic or chemoresponsive particle . Indeed, since its first description for ZIF‐8 and various metal, metal–oxide, and metal–sulfide nanoparticles, the approach has been extended to a variety of MOFs, including UiO‐66 and UiO‐67, MIL‐53, MOF‐801, and others …”