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Efficient utilization of methane via catalytic complete combustion is a very important pathway to realize energy efficiency and pollution reduction. From the viewpoint of structural design, herein a green water‐phase route is developed to prepare ultrathin Co(OH)2 nanosheet supported Pd catalysts. As a platform, the as‐obtained Pd/Co(OH)2 nanosheets are able to be further used to load CeO2 nanoparticles to form 2D nanostructured Pd/CeO2/Co(OH)2 multicomponent hybrids, and further calcination can result in the final well‐crystallized ultrathin Co3O4 nanosheet supported PdO/CeO2 catalysts. Catalytic tests on methane combustion reveal that CeO2 as a catalytic assistant greatly boosts the catalytic performance of PdO/Co3O4 via strong synergetic effects with Pd species and Co3O4 components. The best sample of PdO/CeO2‐0.1/Co3O4 exhibits surprisingly enhanced light‐off activity, indicating that such 2D Co3O4 nanosheet supported nanocatalysts might show promising prospect for heterogeneous catalysis. [ABSTRACT FROM AUTHOR]

Herein, an effective top‐down etching route is presented to in situ fabricate CuO/CeO2 nanohybrids on the surface of Cu2O microcube templates. This method has well taken into account the factors both in thermodynamics and in kinetics, including surface structural nanocrystallization, construction of mesopores, formation of stable core@shell structures, and strengthened synergistic effects, in order to realize the structural design and hence greatly improve catalytic performance caused by surface nanocrystallization of Cu2O cubes. After etched by aid of ammonia and Ce3+ ions the final products are in a well‐defined spiny yolk@shell structures, in which the unetched part of Cu2O cubes serves as the core and the shell is composed by the CuO nanothorns encapsulated by CeO2 nanoparticles. Systematical characterizations including scanning electron microscopy, transmission electron microscopy, X‐ray diffraction, X‐ray photoelectron spectroscopy, H2‐temperature programmed reduction, N2 sorption, firmly disclose the relationship between the catalytic properties and the structures of samples. By simply tuning the usage amount of ammonia and Ce3+ ions, the samples show a typical volcano curve in the model reaction of catalytic CO oxidation. Sample CuO@CeO2‐0.05 exhibits the optimal catalytic activity and stability. It is believed that this top‐down strategy has shown promising future to design high‐performance catalysts for the practical need of application. An effective top‐down route is presented to in situ fabricate CuO/CeO2 nanohybrids on the surface of Cu2O microcube templates. After etched by aid of ammonia and Ce3+ ions the products are in well‐defined spiny yolk@shell structures, which show excellent catalytic performance on catalytic CO oxidation. [ABSTRACT FROM AUTHOR]

Widely acknowledged that the capacity of Li-O 2 batteries (LOBs) should be strongly determined by growth behaviors of the discharge product of lithium peroxide (Li 2 O 2 ) that follows both coexisting surface and solution pathways. However until now, it remains still challenging to achieve dynamic modulation on Li 2 O 2 morphologies. Herein, the photo-responsive Au nanoparticles (NPs) supported on reduced oxide graphene (Au/rGO) have been utilized as cathode to manipulate oxygen reduction reaction (ORR) kinetics by aid of surface plasmon resonance (SPR) effects. Thus, we can experimentally reveal the importance of matching ORR kinetics with Li + migration towards battery performance. Moreover, it is found that Li + concentration polarization caused "sudden death" of LOBs is supposed to be just a form of suspended animation that could timely recover under irradiation. This work provides us an in-depth explanation on the working mechanism of LOBs from a kinetic perspective, offering valuable insights for the future battery design., (© 2024 Wiley‐VCH GmbH.)

Superior high-rate performance and ultralong cycling life have been constantly pursued for rechargeable sodium-ion batteries (SIBs). In this work, a facile strategy is employed to successfully synthesize porous Co x P hierarchical nanostructures supported on a flexible carbon fiber cloth (Co x P@CFC), constructing a robust architecture of ordered nanoarrays. Via such a unique design, porous and bare structures can thoroughly expose the electroactive surfaces to the electrolyte, which is favorable for ultrafast sodium-ion storage. In addition, the CFC provides an interconnected 3D conductive network to ensure firm electrical connection of the electrode materials. Besides the inherent flexibility of the CFC, the integration of the hierarchical structures of Co x P with the CFC, as well as the strong synergistic effect between them, effectively help to buffer the mechanical stress caused by repeated sodiation/desodiation, thereby guaranteeing the structural integrity of the overall electrode. Consequently, Co x P@CFC as an anode shows a record-high capacity of 279 mAh g -1 at 5.0 A g -1 with almost no capacity attenuation after 9000 cycles., (© 2022 Wiley-VCH GmbH.)

In this work, we have successfully triggered the aqueous auto-redox reactions between reductive Ce(OH) 3 and oxidative MnO 4 - /Pd 2+ ions to form PdO/Mn 3 O 4 /CeO 2 (PMC) nanocomposites. PMC could spontaneously self-assemble into compact encapsulation on the surface of halloysite nanotubes (HNTs) to form the final one dimensional HNTs supported PMCs (HPMC). It is identified that there exists strong synergistic effects among the components of PdO, Mn 3 O 4 , and CeO 2 , and hence HPMC could show excellent performance on photoassisted thermal catalytic CH 4 combustion that its light-off temperature was sharply reduced to be 180 °C under visible light irradiation. Based on detailed studies, it is found that the catalytic reaction process well follows the classic MVK mechanism, and adsorption/activation of O 2 into active oxygen species (O*) should be the rate-determining step for CH 4 conversion., (© 2021 Wiley-VCH GmbH.)

Inorganic nanomaterials have attracted much attention as enzyme mimics because of simple and stable spatial conformation of those artificially synthesized nanocatalysts. Cu 2 O, as an important kind of narrow band gap semiconductor, is identified as effective as visible-light-driven photocatalysts, which can catalyze decomposition of H 2 O 2 into reactive oxygen species. Moreover, after forming Cu x O/CeO 2 hybrids, the strongly coupled interface between the two components will further improve their catalytic performance. In this paper, the authors try to construct FTO/TiO 2 /Cu x O/CeO 2 (1 < x < 2) nanohybrids with such a kind of active interface via a layer-by-layer electrodeposition strategy by aid of the following surface etching process. It is found that FTO/TiO 2 /Cu x O/CeO 2 exhibits good peroxidase mimic activity in the dark but much better performance under visible light irradiation (λ ≥ 420 nm) during catalytic oxidation of 3,3',5,5'-tetramethylbenzidine substrates in the presence of H 2 O 2 . Detailed characterizations disclose that the construction of TiO 2 /Cu 2 O pn-heterojunctions do effectively accelerate separation of photogenerated carriers, and the formation of a highly active Cu x O/CeO 2 interface is synergistically favorable for selectively generating singlet oxygen to boost the catalytic performance of FTO/TiO 2 /Cu x O/CeO 2 ., (© 2021 Wiley-VCH GmbH.)

Pd@CeO 2 /Al 2 O 3 catalysts are of great importance for real applications, such as three-way catalysis, CO oxidation, and methane combustion. In this article, the Pd@CeO 2 core@shell nanospheres are prepared via the autoredox reaction in aqueous phase. Three kinds of methods are then employed, that is, electrostatic interaction, supramolecular self-assembly, and physical mixing, to support the as-prepared Pd@CeO 2 nanospheres on γ-Al 2 O 3 . A model reaction of catalytic methane-combustion is employed here to evaluate the three Pd@CeO 2 /γ-Al 2 O 3 samples. As a result, the sample Pd@CeO 2 -S-850 prepared via supramolecular self-assembly and calcined at 850 °C exhibits superior catalytic performance to the others, which has a far lower light-off temperature (T 50 of about 364 °C). Moreover, almost no deterioration of Pd@CeO 2 -S-850 is observed after five sequent catalytic cycles. The analysis of H 2 -TPR curves concludes that there exists hydrogen spillover related to the strong metal-support interaction between Pd species and oxides. The strong metal-support interaction and the specific surface areas might be responsible for the catalytic performance of the Pd@CeO 2 samples toward catalytic methane combustion., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

In this paper, we report an efficient strategy for the synthesis of Cu/Co double-doped CeO 2 nanospheres (Cu x Co 1- x -CeO 2 -Pt, 0 ≤ x ≤ 1), which were fabricated via a simple water-glycol system. The following in situ surface decoration of Pt nanoparticles make these nanospheres highly active for the catalytic reduction of nitrophenol and CO oxidation. Detailed tests show that their catalytic performance strongly depends on the doping components and ion concentration of Cu and Co ions. The best samples of Cu 0.50 Co 0.50 -CeO 2 -Pt and Cu 0.34 Co 0.66 -CeO 2 -Pt demonstrate an excellent turnover frequency (TOF) of more than 450 h -1 after five cycles and retains about 99% conversion by using NH 3 BH 3 as a reductant to reduce nitrophenol. Moreover, Cu 0.50 Co 0.50 -CeO 2 -Pt possesses a much lower light-off and T 100 (the temperature for 100% CO oxidation) temperature compared with the other catalysts.

A galvanic replacement strategy has been successfully adopted to design Ag x Au 1- x @CeO 2 core@shell nanospheres derived from Ag@CeO 2 ones. After etching using HAuCl 4 , the Ag core was in situ replaced with Ag x Au 1- x alloy nanoframes, and void spaces were left under the CeO 2 shell. Among the as-prepared Ag x Au 1- x @CeO 2 catalysts, Ag 0.64 Au 0.36 @CeO 2 shows the optimal catalytic performance, whose catalytic efficiency reaches even 2.5 times higher than our previously reported Pt@CeO 2 nanospheres in the catalytic reduction of 4-nitrophenol (4-NP) by ammonia borane (AB). Besides, Ag 0.64 Au 0.36 @CeO 2 also exhibits a much lower 100% conversion temperature of 120 °C for catalytic CO oxidation compared with the other samples.