Synergistic Catalysis of Methane Combustion Using Cu–Ce–O Hybrid Nanoparticles with High Activity and Operation Stability

Abstract

A new CuO–CeO2 hybrid nanoparticle (Cu­CeO x -NP) with a tunable homogeneous chemical composition was successfully prepared for high-performance catalytic methane combustion. The substantial amounts of Cu–Ce–O interfaces were created for enhanced catalysis using gas-phase evaporation-induced self-assembly. The Cu­CeO x -NP exhibited an ultralow light-off temperature (320 °C), high activity, selectivity, and operation stability for catalytic methane combustion. The optimal reducibility and the corresponding catalytic activity of Cu­CeO x -NP were achieved when the molar fraction of Ce was 0.17. The operation stability increased as the concentration ratio of oxygen in the reactant gas and the corresponding oxidation rate of carbon species from the catalyst surface increased. This work demonstrates a facile route for controlled synthesis of Cu­CeO x -NP. The mechanistic understanding of synergistic catalysis developed in this study can be used to further enhance activity of methane combustion and reduce environmental pollution for alternative energy applications.

CuO Nanoplatelets with Highly Dispersed Ce-Doping Derived from Intercalated Layered Double Hydroxides for Synergistically Enhanced Oxygen Reduction Reaction in Al–Air Batteries

“…The Ce 3d spectrum suggests the coexistence of Ce 3+ and Ce 4+ species with Ce 4+ being the main valence state in the Cu–Ce–O oxide. Oxygen vacancies and unsaturated chemical bonds are introduced in the crystal to create a charge imbalance resulting from the presence of Ce 3+ in CeO 2 nanocrystals . The surface area was further investigated by N 2 -adsorption/desorption measurements.…”

“…Conversely, the bare CFP and pristine CB show insignificant activity toward the ORR during the battery discharge. Many reports have inferred that the CeO 2 often acts as an oxygen buffer that can store O 2 in an oxygen-rich condition and remove it in an oxygen-insufficient condition because of the Ce 4+ /Ce 3+ redox couple. ,− As a result, the presence of CeO 2 on the catalyst surface would easily transfer O 2 to the contiguous Cu–O active sites . During the redox process, these factors are helpful to the catalytic activity in accordance with the Mars–Krevelen redox mechanism .…”

“…After thermal decomposition, LDHs lose their layered structure and form mixed metal oxides with high stability, large specific surface area, and high metal dispersion, which lead to extensive applications of these materials. , Moreover, compared with the materials prepared by other techniques (e.g., hydrothermal or nanocasting routes), the catalysts derived from LDH precursors are generally characterized by higher activities and longer lifetimes. ,, In this work, we developed a facile and scalable method to produce Ce-containing ternary LDH composite precursors for mass production of Cu–Ce–O nanocomposites with highly dispersed metal ions. Cu is the active component for ORR, whereas Ce could promote the reducibility of Cu and increase the dispersion of Cu. , As a result of the “Jahn–Teller effect” of the Cu ion, the Zn element was added to stabilize the host layer of LDH during preparation and increase the catalyst surface area after the alkali leaching treatment . The newly developed Cu–Ce–O-based catalysts demonstrate efficient ORR electrocatalytic performance with superior durability and show potential applications in Al-air batteries for the first time.…”

Synergy effect of CuO on CuCo2O4 for methane catalytic combustion

“…There is literature showing that CuO has excellent methane adsorption capacity, which may also be one of the reasons for the increased activity of the (CuO) 0.2 –CuCo 2 O 4 composite oxide to catalyze methane combustion. 43 Table 2 shows the results of the catalytic methane combustion of different catalysts, and the (CuO) 0.2 –CuCo 2 O 4 composites oxide still has excellent catalytic activity compared to these catalysts. In Table 2 , the reaction conditions of various catalysts are different, so there is no way to make a direct comparison, only a rough comparison of their catalytic activities.…”

The influence of dust originating from carbon black nanopowders on the explosion characteristics of lean methane/air mixtures within a turbulent environment

“…In a recent study conducted by Abdelsalam et al (2016), the effect of metallic nanoparticles such as Co, Ni and Fe, on biogas and methane production from anaerobic digestion of livestock manure was investigated. Additionally, Lu et al (2016) examined the effects induced by the use of specific metallic nanoparticles as additives for promoting the catalytic activity of methane combustion. From these studies it is understood that the danger derived from accidental ignition of a reactive two-phase mixture is not confined only to coal mining industries, but through the increased use of ENMs, it is likely to spread to other industries.…”