Non-noble, efficient catalyst of unsupported α-Cr2O3 nanoparticles for low temperature CO Oxidation

Abstract

Herein, we report the synthesis of chromium oxide nanoparticles, α -Cr2O3 NPs, followed by full characterization via XRD, SEM, XPS, and N2 sorptiometry. The synthesized nanoparticles were tested as catalysts toward the oxidation of CO. The impact of calcination temperature on the catalytic activity was also investigated. CO conversion (%), light-off temperature, T50, data were determined. The results revealed that chromia obtained at low calcination temperature (400 °C) is more active than those obtained at high calcination temperatures (600° or 800 °C) and this is ascribed to the smaller particle size and higher surface area of this sample. The results revealed a superior catalytic activity of Cr2O3 NPs at lower temperature as we reached a complete conversion at 200 °C which is high value in the forefront of the published results of other non-noble catalysts. The high activity of Cr2O3 nanoparticles (T50 as low as 98 °C) where found to be dependent on a careful selection of the calcination temperature. These results may provide effective and economic solutions to overcome one of the major environmental threats.

Low-Temperature Catalytic CO Oxidation Over Non-Noble, Efficient Chromia in Reduced Graphene Oxide and Graphene Oxide Nanocomposites

“…The peaks at 530 and 531 eV are assignable to lattice oxygen, and this is in accordance with previously reported work [31,32]. The peak located at around 532.4 eV was attributed to surface oxygen species and/or adsorbed surface hydroxyls [32]. TEM image obtained for α-Cr 2 O 3 NPs yielded after calcination at 600 • C is shown in Figure 4 A.…”

“…The O(1s) spectrum monitors a broad peak deconvoluted into three subpeaks at binding energy 530, 531 and 532.4 eV. The peaks at 530 and 531 eV are assignable to lattice oxygen, and this is in accordance with previously reported work [31,32]. The peak located at around 532.4 eV was attributed to surface oxygen species and/or adsorbed surface hydroxyls [32].…”

“…The dose of examined material: 250-300 mg The mass ratio 1CO to 3O2 304 132 [32] Cr2O3 In the case of the hybrid catalysts, Cr 2 O 3 is dispersed well in the carbonaceous material, which prevents its aggregation, therefore maintaining its stability at the conversion rate for a long time.…”

“…The catalytic activity of the investigated catalysts for CO oxidation was tested using a tubular reactor adopting the same method previously reported [32]. The test catalyst powder was weighed out to 300 mg and placed on a G1-porous quartz disc mounted in the middle of a tubular reactor with an inner diameter of 2 cm and a length of 15 cm.…”

In‐situ Glycine Sensor Development Based ZnO/Al2O3/Cr2O3 Nanoparticles

“…The spin energy separation of Zn2p level is equal to 23.2 eV representing the oxidation sate of Zn 2+ ,. In Figure (b), the O1s shows one high intense peak at 531.0 eV indicating lattice oxygen with oxidation state of O 2− in sample ZnO/Al 2 O 3 /Cr 2 O 3 NPs ,. The XPS spectra of Cr2p is demonstrated in Figure (c) with two spin orbitals centered at 577.3 and 587.2 eV for Cr2p 3/2 and Cr2p 1/2 correspondingly.…”