Total oxidation of methane over Pd catalysts supported on silicon nitrideInfluence of support nature

Курзина, И. А.; Aires, F.J. Cadete Santos; Bergeret, G.; Bertolini, J.C.

doi:10.1016/j.cej.2004.12.009

Cited by 24 publications

(11 citation statements)

References 32 publications

(36 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Compared with M/SiCN nanocomposites, the design of M/Si-based nitride nanocomposites systems (i.e., M/Si 3 N 4 ) is much more challenging, whereas the silicon nitride matrix could contribute to the catalytic activity of the whole system [ 23 , 24 , 25 , 26 , 27 , 28 ]. This might be due to the systematically thermodynamically-controlled formation of metal nitride through the reaction of the metal cations chemically-bonded and/or physically-loaded to the polysilazane with ammonia (NH 3 ), which is used as extrinsic nitrogen source for the formation of Si 3 N 4 .…”

Section: Introductionmentioning

confidence: 99%

Mechanistic Investigation of the Formation of Nickel Nanocrystallites Embedded in Amorphous Silicon Nitride Nanocomposites

et al. 2022

View full text Add to dashboard Cite

Herein, we report the mechanistic investigation of the formation of nickel (Ni) nanocrystallites during the formation of amorphous silicon nitride at a temperature as low as 400 °C, using perhydropolysilazane (PHPS) as a preformed precursor and further coordinated by nickel chloride (NiCl2); thus, forming the non-noble transition metal (TM) as a potential catalyst and the support in an one-step process. It was demonstrated that NiCl2 catalyzed dehydrocoupling reactions between Si-H and N-H bonds in PHPS to afford ternary silylamino groups, which resulted in the formation of a nanocomposite precursor via complex formation: Ni(II) cation of NiCl2 coordinated the ternary silylamino ligands formed in situ. By monitoring intrinsic chemical reactions during the precursor pyrolysis under inert gas atmosphere, it was revealed that the Ni-N bond formed by a nucleophilic attack of the N atom on the Ni(II) cation center, followed by Ni nucleation below 300 °C, which was promoted by the decomposition of Ni nitride species. The latter was facilitated under the hydrogen-containing atmosphere generated by the NiCl2-catalyzed dehydrocoupling reaction. The increase of the temperature to 400 °C led to the formation of a covalently-bonded amorphous Si3N4 matrix surrounding Ni nanocrystallites.

show abstract

Section: Introductionmentioning

confidence: 99%

Mechanistic Investigation of the Formation of Nickel Nanocrystallites Embedded in Amorphous Silicon Nitride Nanocomposites

et al. 2022

View full text Add to dashboard Cite

show abstract

“…Pd supported catalysts are successful used in a variety of very different reactions such as the low-temperature butadiene hydrogenation both in liquid [24] and gas phases [25,26], the rather high temperature reaction of methane total oxidation [27][28][29], three-way catalysis [30] reduction reactions [31] or cross-coupling reactions [32] such as the well know Suzuki-Miyaura reaction [33]. Development of Pd-based bimetallic supported catalysts have thus found an immense success amid the catalysis community since they allow the tuning and refinement of the already remarkable catalytic properties of pure Pd [9,12,20,21]; for instance, to stabilize the catalyst in presence of poisons [19] or to improve its selectivity [34].…”

Section: Introductionmentioning

confidence: 99%

Preparation and Investigation of Pd and Bimetallic Pd-Sn Nanocrystals on γ-Al2O3

et al. 2021

View full text Add to dashboard Cite

One of the key factors for producing highly dispersed controlled nanoparticles is the method used for metal deposition. The decomposition of metal-organic precursors is a good method for deposition of metal nanoparticles with very small sizes and narrow size distributions on the surface of various supports. The preparation process of Pd and bimetallic Pd-Sn nanoparticles supported onto γ‑Al2O3 is considered. The samples were prepared by diffusional co-impregnation of the γ‑Al2O3 support by using organometallic Pd(acac)2 and Sn(acac)2Cl2 precursors. To achieve the formation of Pd and bimetallic Pd-Sn nanoparticles on the support surface, the synthesized samples were then subjected to thermal decomposition under Ar (to decompose the organometallic bound to the surface while keeping the formed nanoparticles small) followed by an oxidation in O2 (to eliminate the organic compounds remaining on the surface) and a reduction in H2 (to reduce the nanoparticles oxidized during the previous step). A combination of methods (ICP-OES, TPR-H2, XPS, TEM/EDX) was used to compare the physical-chemical properties of the synthesized Pd and bimetallic Pd-Sn nanoparticles supported on the γ‑Al2O3. The three samples exhibit narrow size distribution with a majority on nanoparticles between 3 and 5 nm. Local EDX measurements clearly showed that the nanoparticles are bimetallic with the expected chemical composition and the measured global composition by ICP-OES. The surface composition and electronic properties of Pd and Sn on the γ-Al2O3 support were investigated by XPS, in particular the chemical state of palladium and tin after each step of thermal decomposition treatments (oxidation, reduction) by the XPS method has been carried out. The reducibility of the prepared bimetallic nanoparticles was measured by hydrogen temperature programmed reduction (TPR-H2). The temperature programmed reduction TPR-H2 experiments have confirmed the existence of strong surface interactions between Pd and Sn, as evidenced by hydrogen spillover of Pd to Sn (Pd-assisted reduction of oxygen precovered Sn). These results lead us to propose a mechanism for the formation of the bimetallic nanoparticles.

show abstract

“…[9][10][11][12][13][14][15][16][17] Therein, silicon nitride (Si 3 N 4 ) as a nitride material is known for its excellent mechanical properties, and good chemical and thermal stability even at high temperature. [18][19][20][21] However, the insufficient electrical conductivity and the weak interaction with the platinum (Pt) of Si 3 N 4 are the major obstacles for its use in DMFCs, restricting the electrocatalytic performance of the electrocatalysts.…”

Section: Introductionmentioning

confidence: 99%

Si₃N₄whiskers modified with titanium as stable Pt electrocatalyst supports for methanol oxidation and oxygen reduction

et al. 2014

View full text Add to dashboard Cite

Total oxidation of methane over Pd catalysts supported on silicon nitrideInfluence of support nature

Cited by 24 publications

References 32 publications

Mechanistic Investigation of the Formation of Nickel Nanocrystallites Embedded in Amorphous Silicon Nitride Nanocomposites

Mechanistic Investigation of the Formation of Nickel Nanocrystallites Embedded in Amorphous Silicon Nitride Nanocomposites

Preparation and Investigation of Pd and Bimetallic Pd-Sn Nanocrystals on γ-Al2O3

Si₃N₄whiskers modified with titanium as stable Pt electrocatalyst supports for methanol oxidation and oxygen reduction

Contact Info

Product

Resources

About

Total oxidation of methane over Pd catalysts supported on silicon nitrideInfluence of support nature

Cited by 24 publications

References 32 publications

Mechanistic Investigation of the Formation of Nickel Nanocrystallites Embedded in Amorphous Silicon Nitride Nanocomposites

Mechanistic Investigation of the Formation of Nickel Nanocrystallites Embedded in Amorphous Silicon Nitride Nanocomposites

Preparation and Investigation of Pd and Bimetallic Pd-Sn Nanocrystals on γ-Al2O3

Si3N4whiskers modified with titanium as stable Pt electrocatalyst supports for methanol oxidation and oxygen reduction

Contact Info

Product

Resources

About

Si₃N₄whiskers modified with titanium as stable Pt electrocatalyst supports for methanol oxidation and oxygen reduction