Bimetallic NiCo/AC Catalysts with a Strong Coupling Effect for High-Efficiency Hydrogenation of N-Ethylcarbazole

Abstract

Liquid organic hydrogen carrier technology (LOHC) is considered to be the most promising solution for hydrogen storage and transport, but its development is limited by the high cost of noble metal catalysts. In this paper, four kinds of Ni/Co bimetallic catalysts with different proportions were prepared by the impregnation method. The effects of the Ni/Co molar ratio and the reduction temperature on the hydrogenation performance of N-ethylcarbazole (NEC) were studied. The relationship between the structure and the properties of the catalyst was discussed by combining various characterization methods. The results show that when cobalt is added to 50%, the hydrogenation activity is the most significant. Meanwhile, 100% of NEC conversion and 98.99% of 12H-NEC selectivity were achieved. The hydrogenation capacity is 5.77 wt %, when the catalyst reduction temperature is 450 °C. The characterizations show that the two metals are uniformly doped and highly dispersed with a good pore structure, and the metal particles have good alloy morphology. The synergistic interaction between Ni/Co metals is the key factor for the remarkable catalytic activity of the catalyst. The design and application of highly efficient nonprecious metal hydrogenation catalysts provide more feasibility to promote the commercial development of liquid organic hydrogen carrier technology.

A Perspective Review on N-Heterocycles as Liquid Organic Hydrogen Carriers and Their Hydrogenation/Dehydrogenation Catalysts

“…The Ni−Co/AC catalyst achieves 100% conversion and 99% selectivity, with a hydrogenation capacity of up to 5.77 wt %. 107 Conventional methods for preparing loaded nanocatalysts usually require significant amounts of surfactants and stabilizers to prevent nanoparticle agglomeration. However, without the introduction of other chemical reducing agents, ultrasound-assisted reduction can achieve high catalytic activity and catalyst stability.…”

“…Rapid dispersion of Ni and inhibition of carbon deposition at Ni sites are promoted by the introduction of Co. The Ni–Co/AC catalyst achieves 100% conversion and 99% selectivity, with a hydrogenation capacity of up to 5.77 wt % …”

V-Promoted Ultrasmall Pd Nanoparticles Supported on V-KIT-6 for the Enhanced Catalytic Dehydrogenation of Perhydro-N-ethylcarbazole

“…3 It has received significant attention due to this advantage and has been extensively researched and documented. 4,5 Compared with hydrogenation, dehydrogenation is a thermodynamically unfavorable reaction. The bond energy of C−H is higher than that of the C−C bond, making C−H activation difficult.…”

“…LOHCs are of vital importance materials for H 2 storage due to their high storage capacity, stability, and liquid form at room temperature and pressure. , N -Ethylcarbazole (NEC) is a highly representative candidate due to its H 2 capacity of 5.8 wt % and ability to uptake and release hydrogen reversibly at temperatures below 200 °C . It has received significant attention due to this advantage and has been extensively researched and documented. , Compared with hydrogenation, dehydrogenation is a thermodynamically unfavorable reaction. The bond energy of C–H is higher than that of the C–C bond, making C–H activation difficult .…”

Operando Investigation on the Role of Densification and Chemo‐Mechanics on Solid‐State Cathodes

“…Continuous contact between the cathode active material and the solid electrolyte phase is desirable in order to avoid deleterious current focusing and cathode active material fracture during cycling. [16] However, solid-state cathodes experience chemo-mechanical loads during electrochemical cycling. These dynamic loads can induce internal strain at the cathode and drive interfacial contact loss, particle fracture, and increases in the porosity or void region in the composite cathode.…”