Ni Nanoparticles Grown on SiO₂ Supports Using a Carbon Interlayer Sacrificial Strategy for Chemoselective Hydrogenation of Nitrobenzene and m-Cresol

Abstract

To efficiently increase the dispersity of metal nanoparticles (NPs) of the supported-type catalyst is crucial for promoting their catalytic performance owing to the enlarged amount of exposed active sites and the strengthened metal–support interaction. Therefore, to develop a facile and practical method for preparing a supported-type catalyst with high dispersity is of great significance, but remains a challenge. In this work, inspired by the previously reported non-noble metal sacrificial approach, we report a facile and practical carbon interlayer sacrificial (CIS) strategy for preparing supported Ni NP catalysts on silica rod (10%Ni/r-SiO2-CIS) with high dispersity. This strategy involves two steps: one is depositing carbon on silica rod (r-SiO2) to form the corresponding carbon-coated silica (r-SiO2@C) carrier through a hydrothermal process in the presence of glucose; the other is loading metal precursor on r-SiO2@C through an incipient wetness impregnation (IWI) process followed by hydrogenation for carbon elimination. The method has been extended to the preparation of supported Ni NPs on the silica sphere (10%Ni/s-SiO2-CIS) with high Ni dispersity by using the silica sphere (s-SiO2) as the carrier. For comparison, the conventional-supported Ni NP catalysts (10%Ni/r-SiO2 and 10%Ni/s-SiO2) were also prepared by using a similar method to that for 10%Ni/r-SiO2-CIS and 10%Ni/s-SiO2-CIS except for absence of the carbon-coating process. Owing to the more exposed active sites and the strengthened metal–support resulting from the higher Ni dispersity, both 10%Ni/r-SiO2-CIS and 10%Ni/s-SiO2-CIS catalysts show much superior catalytic properties for the chemoselective hydrogenation of nitrobenzene and m-cresol to their corresponding 10%Ni/r-SiO2 and 10%Ni/s-SiO2. This work opens up an avenue for designing and preparing other outstanding supported metal NP catalysts with high metal dispersity for diverse catalytic transformations.

Nickel Nanoparticles: Insights into Sintering Dynamics

“…A broad range of applications was found for nickel nanoparticles (Ni NPs), which can be used in electrocatalysis, photocatalysis, or biomedicine [10,11]. These unique properties of NPs as catalysts derive from the large percentage of coordinatively unsaturated atoms located at the surface, edges, and corners of the NPs compared to the total number of atoms [12].…”

Synthesis of Mesoporous Silica-Supported NiCo Bimetallic Nanocatalysts and Their Enhanced Catalytic Hydrogenation Performance

“…However, the high cost and scarcity of resources with noble metals limit their industrial applications. Transition metals, including Ni, − Cu, , Fe, , and Co, − are promising alternatives due to their abundant reserves, low cost, and good catalytic performance under certain conditions. For instance, 10%Ni/r–SiO 2 –CIS illustrated good catalytic activity for nitrobenzene hydrogenation under the reaction condition of 150 °C and 1.0 MPa of H 2 , while Ni@NCQDs achieved high activity (100%) and selectivity (99.8%) for the reduction of p -chloronitrobenzene to p -chloroaniline.…”

“…Transition metals, including Ni, − Cu, , Fe, , and Co, − are promising alternatives due to their abundant reserves, low cost, and good catalytic performance under certain conditions. For instance, 10%Ni/r–SiO 2 –CIS illustrated good catalytic activity for nitrobenzene hydrogenation under the reaction condition of 150 °C and 1.0 MPa of H 2 , while Ni@NCQDs achieved high activity (100%) and selectivity (99.8%) for the reduction of p -chloronitrobenzene to p -chloroaniline. Ni/CeO 2 -CAS catalysts showed good catalytic performance for the reduction of various nitroarenes under 120 °C and 2.0 MPa of H 2 , and the Co/MA-800 nanocatalysts were active for the reductive amination of nitroarenes to obtain imines with high yields of product.…”

Preparation of mesoporous chitosan iron supported nano-catalyst for the catalyzed oxidation of primary amine to imine

“…Studies have shown that a suitable combination of metal and support, the design of an efficient supported metal nanoparticle catalyst, and the use of metal–support interaction, can improve the dispersion of metal nanoparticles and effectively reduce the agglomeration of nanoparticles during the catalytic process. 28 Ma et al 16 successfully synthesized a supported nano-catalyst in which the non-noble metal Fe was supported on nitrogen-doped porous carbon derived from biomass, which was used to efficiently catalyze the oxidation of primary amine to imine with air as an oxidizing agent. Chen et al 17 reported a supported nano-catalyst with a mesoporous medium, homogeneous metal NPs and abundant oxygen vacancies for the synthesis of imines.…”