Synthesis, Characterization and Catalytic Activity of Ternary Oxide Catalysts Using the Microwave-Assisted Solution Combustion Method

Abstract

Ni−Co−Al, Ni−Cu−Al and Co−Cu−Al ternary oxide catalysts, with a fixed 5 wt% transition metal loading, were prepared by the microwave-assisted solution combustion method and tested in CO oxidation. The bulk and surface properties of the catalysts were investigated, using XRD, N2 adsorption–desorption, SEM, XPS and TEM techniques. XRD, XPS and TEM results revealed that nickel and cobalt were present as spinels on the surface and in the bulk. Differently, copper was preferentially present in “bulk-like” CuO-segregated phases. No interaction between the couples of transition metal species was detected, and the introduction of Cu-containing precursors into the Ni−Al or Co−Al combustion systems was not effective in preventing the formation of NiAl2O4 and CoAl2O4 spinels in the Ni− or Co-containing catalysts. Copper-containing catalysts were the most active, indicating that copper oxides are the effective active species for improving the CO oxidation activity.

CoAl2O4-Anchored Carbon Nanofiber Electrodes for Indomethacin Sensing in Water and Biological Samples

“…From the SAED pattern, the orientation of the CoAl 2 O 4 particles was confirmed by the well-defined concentric diffraction rings shown in Figure (G). The rings correspond to the (220) and (311) diffraction planes, which is consistent with the XRD pattern of CoAl 2 O 4 , and the outermost ring corresponds to the α-Al 2 O 3 (300) plane Figure (H–L) depicts the atomic distribution of Co, Al, O, and C in CoAl 2 O 4 /f-CNF, which is confirmed by EDAX mapping.…”

MOP−18−Derived CuO Fiber for Hybrid Supercapacitor Electrodes

“…Figure 7 illustrates the nitrogen adsorption-desorption isotherm for micronized MM12. Before the analysis at 77 K, the sample was degassed for 24 h at a temperature of 250 • C. The MM12 fibers exhibited a type IV gas adsorption-desorption isotherm, characterized by a relatively minor hysteresis [41]. Both the pore size distribution and the gas adsorptiondesorption isotherm suggest a low porosity.…”

Optimizing CO2 methanation: effect of surface basicity and active phase reducibility on Ni-based catalysts

“…in improved catalytic activity. 48 In this regard, Co exhibited superior methanation activity when incorporated alongside Ni on Al 2 O 3 support compared to Fe and Mo. 42 This points toward the potential of bimetallic catalysts to enhance catalytic properties through modifications in Ni dispersion, the fundamental characteristics of the support, and the Ni-support interaction.…”

“…40 Indeed, while single metal oxide catalysts are subject to poisoning and low thermal stability, the use of multiple oxides can help overcome these problems and achieve enhanced properties, such as better metal dispersion, resulting in improved catalytic activity. 48 In this regard, Co exhibited superior methanation activity when incorporated alongside Ni on Al 2 O 3 support compared to Fe and Mo. 42 This points toward the potential of bimetallic catalysts to enhance catalytic properties through modifications in Ni dispersion, the fundamental characteristics of the support, and the Ni–support interaction.…”