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Widely acknowledged that the capacity of Li‐O2 batteries (LOBs) should be strongly determined by growth behaviors of the discharge product of lithium peroxide (Li2O2) that follows both coexisting surface and solution pathways. However until now, it remains still challenging to achieve dynamic modulation on Li2O2 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. [ABSTRACT FROM AUTHOR]

Formula regulation of multi‐component catalysts by manual search is undoubtedly a time‐consuming task, which has severely impeded the development efficiency of high‐performance catalysts. In this work, PtPd@CeZrOx core–shell nanospheres, as a successful case study, is explicitly demonstrated how Bayesian optimization (BO) accelerates the discovery of methane combustion catalysts with the optimal formula ratio (the Pt/Pd mole ratio ranges from 1/2.33–1/9.09, and Ce/Zr from 1/0.22–1/0.35), which directly results in a lower conversion temperature (T50 approaching to 330 °C) than ones reported hitherto. Consequently, the best sample obtained could be efficiently developed after two rounds of iterations, containing only 18 experiments in all that is far less than the common human workload via the traditional trial‐and‐error search for optimal compositions. Further, this BO‐based machine learning strategy can be straightforward extended to serve the autonomous discovery in multi‐component material systems, for other desired properties, showing promising opportunities to practical applications in future. [ABSTRACT FROM AUTHOR]

The theoretically high‐energy‐density lithium–sulfur batteries (LSBs) are seriously limited by the disadvantages including the shuttle effect of soluble lithium polysulfides (LiPSs) and the sluggish sulfur redox kinetics, especially for the most difficult solid–solid conversion of Li2S2 to Li2S. Herein, a multifunctional catalytic interlayer to improve the performance of LSBs is tried to introduce, in which Fe1–xS/Fe3C nanoparticles are embedded in the N/S dual‐doped carbon network (NSC) composed by nanosheets and nanotubes (the final product is named as FeSC@NSC). The well‐designed 3D NSC network endows the interlayer with a satisfactory LiPSs capture‐catalytic ability, thus ensuring fast redox reaction kinetics and suppressing LiPSs shuttling. The density functional theory calculations disclose the catalytic mechanisms that FeSC@NSC greatly improves the liquid–solid (LiPSs to Li2S2) conversion and unexpectedly the solid–solid (Li2S2 to Li2S) one. As a result, the LSBs based on the FeSC@NSC interlayer can achieve a high specific capacity of 1118 mAh g−1 at a current density of 0.2 C, and a relatively stable capacity of 415 mAh g−1 at a large current density of 2.0 C after 700 cycles as well as superior rate performance. [ABSTRACT FROM AUTHOR]

In this work, we have successfully triggered the aqueous auto‐redox reactions between reductive Ce(OH)3 and oxidative MnO4−/Pd2+ ions to form PdO/Mn3O4/CeO2 (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, Mn3O4, and CeO2, and hence HPMC could show excellent performance on photoassisted thermal catalytic CH4 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 O2 into active oxygen species (O*) should be the rate‐determining step for CH4 conversion. [ABSTRACT FROM AUTHOR]

As the key component of a new generation for low‐cost energy storage systems, sodium‐ion batteries (SIBs) have attracted enormous attention and research due to its promising potentiality in large‐scale electrochemical energy storage. For practical application of SIBs, carbonaceous materials have been considered to be one of the best choices for electrodes in virtue of their abundant reserves, low cost, easy availability, and environmental friendliness. 3D carbon network (3D‐carbon) is of particular interests, which has displayed outstanding features, including abundant active sites, interconnected multi‐level pore structures, high electronic conductivity, and excellent mechanical stability. Herein, we review the structural advantages of 3D‐carbon and its preparation methods, and then discuss recent progress in 3D carbon materials and their composites for SIBs. The superior functionalities of 3D‐carbon are emphasized as support templates or encapsulation shell membranes. Finally, we summarize and outline the challenges and future prospects of 3D‐carbon in SIBs. [ABSTRACT FROM AUTHOR]

Inorganic nanomaterials have attracted much attention as enzyme mimics because of simple and stable spatial conformation of those artificially synthesized nanocatalysts. Cu2O, as an important kind of narrow band gap semiconductor, is identified as effective as visible‐light‐driven photocatalysts, which can catalyze decomposition of H2O2 into reactive oxygen species. Moreover, after forming CuxO/CeO2 hybrids, the strongly coupled interface between the two components will further improve their catalytic performance. In this paper, the authors try to construct FTO/TiO2/CuxO/CeO2 (1

The development of efficient catalysts is of great importance for hydrogen evolution reaction (HER) of water splitting via electrocatalytic/photocatalytic processes to remediate the current severe environmental and energy problems. By aid of the stabilization effects of uncoordinated groups and inherent pore‐confinement of amine‐functionalized metal–organic frameworks (NH2‐MIL‐125), two forms of Ru species including nanoparticles (NPs) and/or single atoms (SAs) can be firmly embedded in NH2‐MIL‐125 derived N‐doped TiO2/C support (N‐TC), and thus obtain two kinds of samples named Ru‐NPs/SAs@N‐TC and Ru‐SAs@N‐TC, respectively. In the synthetic process, the initial feeding amount of Ru3+ ions not only strongly determines the final size and dispersion states of Ru species but also the morphology and defective structures of N‐TC support. Impressively, Ru‐NPs/SAs@N‐TC exhibit superior catalytic activities to Ru‐SAs@N‐TC for either electrocatalytic or photocatalytic HER. This should be attributed to its larger specific surface area and benefiting from synergistic coupling of Ru NPs and Ru SAs. It is envisioned that the present work can provide a new avenue for development of high‐efficiency and multifunctional hybrid catalysts in sustainable energy conversion. [ABSTRACT FROM AUTHOR]

A theoretical and experimental study gives insights into the nature of the metal–boron electronic interaction in boron‐bearing intermetallics and its effects on surface hydrogen adsorption and hydrogen‐evolving catalytic activity. Strong hybridization between the d orbitals of transition metal (TM) and the sp orbitals of boron exists in a family of fifteen TM–boron intermatallics (TM:B=1:1), and hydrogen atoms adsorb more weakly to the metal‐terminated intermetallic surfaces than to the corresponding pure metal surfaces. This modulation of electronic structure makes several intermetallics (e.g. PdB, RuB, ReB) prospective, efficient hydrogen‐evolving materials with catalytic activity close to Pt. A general reaction pathway towards the synthesis of such TMB intermetallics is provided; a class of seven phase‐pure TMB intermetallics, containing V, Nb, Ta, Cr, Mo, W, and Ru, are thus synthesized. RuB is a high‐performing, non‐platinum electrocatalyst for the hydrogen evolution reaction. [ABSTRACT FROM AUTHOR]

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]