Nanoshaped Cerium Oxide with Nickel as a Non-Noble Metal Catalyst for CO2 Thermochemical Reactions

Abstract

Four different nanoshapes of cerium dioxide have been prepared (polycrystals, rods, cubes, and octahedra) and have been decorated with different metals (Ru, Pd, Au, Pt, Cu, and Ni) by incipient wetness impregnation (IWI) and ball milling (BM) methods. After an initial analysis based on oxygen consumption from CO2 pulse chemisorption, Ni-like metal, and two forms of CeO2 cubes and rods were selected for further research. Catalysts were characterized using the Brunauer-Emmett-Teller formula (BET), X-ray spectroscopy (XRD), Raman spectroscopy, scanning electron microscopy (SEM), UV–visible spectrophotometry (UV-Vis), X-ray photoelectron spectroscopy (XPS), temperature programmed reduction (H2-TPR) and CO2 pulse chemisorption, and used to reduce of CO2 into CO (CO2 splitting). Adding metals to cerium dioxide enhanced the ability of CeO2 to release oxygen and concomitant reactivity toward the reduction of CO2. The effect of the metal precursor and concentration were evaluated. The highest CO2 splitting value was achieved for 2% Ni/CeO2-rods prepared by ball milling using Ni nitrate (412 µmol/gcat) and the H2 consumption (453.2 µmol/gcat) confirms the good redox ability of this catalyst.

Ni Nanoparticles Supported on CeO2 as Catalysts for Aqueous-Phase Glycerol Reforming

“…The additional diffraction peaks located at 2θ = 44.5° and 51.8° occur in the patterns of the samples with Ni content above 20%. These two peaks correspond to 111 and 200 diffractions of Ni 0 (JCPDS 04-0850) − and become more intense as the Ni content increases. No diffractions associated with NiO species were observed, indicating that the bulk phase of Ni species has been reduced to produce the metallic Ni state at 300 °C in a hydrogen atmosphere during the synthesis process .…”

“…isotherm according to the International Union of Pure and Applied Chemistry classification, indicating the presence of a mesoporous structure. 28,30 When the relative pressure (P/P 0 ) approaches 1, the adsorption branch of the isotherm shows an upward trend, that is, due to the adsorption of nitrogen in the macropores. 31 It indicates that there is a certain amount of macropores in the catalysts.…”

Ce–Zr–Mn Oxide Catalysts for Soot Combustion: The Role of Preparation Method

“…On the isotherms for the samples of the solvothermal series (CO_st and CMO_st), a hysteresis loop of H2b type is observed (Figure 1c). 29,32,33 The shape of the isotherm and the pronounced maximum on the pore size distribution curves of CO_st (2−5 nm) are a consequence of the denser packing of particles of a uniform size compared to those in the CO_cit sample. The Mn addition to CeO 2 leads to a decrease in the specific surface area with an increase in the V pore due to a change in the particle packing and the formation of wider pores (2−10 nm) for the CMO_st sample (Table 1, Figure 1b).…”

Is the Polish Solar-to-Hydrogen Pathway Green? A Carbon Footprint of AEM Electrolysis Hydrogen Based on an LCA

“…On the other hand, there are different ways of producing hydrogen, with varying and sometimes serious environmental consequences. Among these production technologies, thermochemical, photochemical, photocatalytic [12,13], photoelectrochemical, and biocatalytic processes may be distinguished [14].…”