Nickel Hydroxide–Cobalt Hydroxide Nanoparticle Supported Ruthenium–Nickel–Cobalt Islands as an Efficient Nanocatalyst for the Hydrogenation Reaction

Abstract

The RuNiCo tri-metallic nanocatalyst of Ru islands-on-nickelcobalt/nickel hydroxide-cobalt hydroxide nanoparticles (Ru/ NiCo/Ni(OH) 2 -Co(OH) 2 /C) was prepared at room temperature (RT) via hydrazine hydrater eduction and galvanic replacement methods. And Ru/NiCo/Ni(OH) 2 -Co(OH) 2 /C exhibited much higher catalytic activity in the model reaction of toluene hydrogenationt han Ru/Ni/Ni(OH) 2 /C and Ru/Co/Co(OH) 2 /C due to synergistic effect of Ru, Ni and Co related species, with good stability.In heterogeneous catalysis, multimetallic nanocatalysts( e.g., bimetallic and trimetallic nanocatalysts)h ave important applications.T hese multimetallic nanocatalysts frequently exhibit much higherc atalytic performance, higher selectivity,a nd higher stability and are also cheaper than their corresponding monometallic nanocatalysts. [1][2][3][4][5][6][7][8][9][10][11][12][13][14] For example, Yang et al. successfully prepared PtNiCo, PtNi, and PtCo nanoparticles (NPs) by aw et chemical reduction method with oleic acid as ac apping agents and 1,2-hexadecanediol as ar educing agent, [15] and the NPs were supported on as upport (such as carbon). They found that PtNiCo/C showed better catalytic performance in the CO oxidationr eactiona nd was more stable than either PtNi/C or PtCo/C.T heir results revealed the intrinsic reason was that Co improved the activity,w hereas Ni was responsible for the increased stability.A dditionally,t he Zheng group de-signed and synthesized aP t/FeNi(OH) x catalyst and appliedi t to CO oxidation. The results confirmed that this catalyst had higherc atalytic activity,h ighers tability,a nd more efficient utilization of the Pt atoms than the Pt/Fe(OH) x catalyst mainly as ar esult of interfacial effects in Pt/FeNi(OH) x . [16] However,t he above literature reports mainly focus on the applicationso ft ernary metallicn anocatalysts in heterogeneous catalytic oxidation reactions. There are few reports on the use of trimetallic nanocatalysts to catalyzeh eterogeneoush ydrogenationr eactions. So, it is very necessary to develop ternary metallicn anocatalysts for heterogeneous hydrogenation. Ta ke toluene hydrogenation as an instance, monometallic catalysts, including platinum-based, [17] ruthenium-based, [18][19][20][21][22][23][24] iridiumbased, [25,26] and rhodium-based [27][28][29][30][31][32][33][34] catalysts, have been widely used for this reaction. Someb imetallic nanocatalysts have also been utilized, for instance, Pd-Rh, [35] Pt-Ru, [36] Rh-Pt, [37,38] Ru-Ni, [39] and Rh-Ni [40] catalysts. However,i ti sc hallenging to design and obtain ac atalyst containing an oble metal with excellent catalytic performance under mild conditions and with good stability and high utilization of the precious metal. Herein, we take advantage of at ernary synergistic effect to solve the above problem (such as Ru-Ni-Cosynergy).In this work, bimetallic and trimetallic nanocatalysts with a nanostructure of Ru islands supported on transition-metal/ transition-metal hydroxide NPs and ar elativelyl ow Ru content (3.7 %)...

Literature review: state-of-the-art hydrogen storage technologies and Liquid Organic Hydrogen Carrier (LOHC) development

“…Indeed, hydrogenation with Pt/Al 2 O 3 mixed/diluted with WO 3 / Al 2 O 3 and solid acids showed improved conversion compared to the pristine catalyst due to the LOHC adsorption on acidic sites of the surface [241]. This effect was also observed on a Ru/NiCo/Ni(OH) 2 -Co(OH) 2 -nanoislands supported on carbon catalyst where the combination of the different sites achieved 100% conversion in liquid phase at 60 °C in 1 h for an activity ten times more superior to that of the equivalent Ru/C catalyst [242].…”

NCoCu Carbon Dots Intertwined NiCo Double Hydroxide Nanorod Array for Efficient Electrocatalytic Hydrogen Evolution

“…The peak of 781.7 eV (2p3/2) is assigned to the Co 2 + , which indicates that Co 3 + and Co 2 + coexist in NCoCu-5 CDs/NFÀ CoNi. [44,45] Similar to that of Co, the spectrum of Ni shows multi-valence states in Figure 5f. The peak at 855.3 eV belongs to Ni 2 + in Ni(OH) 2 , and the peak at 856.2 belongs to Ni 3 + in the surface NiOOH.…”

Effect of thermal treatment of Pd decorated Fe/C nanocatalysts on their catalytic performance for formic acid oxidation

“…[13][14][15][16] Most of the studies have focused on bimetallic catalyst systems largely due to the relative simplicity of structural characterization, whereas a limited amount of work has centered on surface oxidized metal species of the bimetallic catalyst including our previous work. 17,18 The fundamental studies on surfaces have exhibited that the activity of an electrocatalyst can be designed by its surface electronic structure, which, if properly controlled, can thoroughly enhance the electrocatalytic activity. [19][20][21][22][23] However, achievement of this enhancement in nanomaterials has been challenging due to its difficulty in controlling surface structure at the nanoscale.…”

“… 13–16 Most of the studies have focused on bimetallic catalyst systems largely due to the relative simplicity of structural characterization, whereas a limited amount of work has centered on surface oxidized metal species of the bimetallic catalyst including our previous work. 17,18 …”