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High-entropy oxide (HEO) materials have recently been extensively studied and attracted unprecedented attention. The HEO can be regulated by introducing different atomic species, resulting in excellent physical properties. Herein, we fabricated the spinel HEO (Cr,Mn,Fe,Co,Ni) 3 O 4 (CMFCN) film with various of thicknesses on perovskite STO substrate by PLD technology. Interestingly, all the CMFCN films exhibit negative Poisson's ratio behavior and demonstrate ferrimagnetic behavior at room temperature. The strain-induced Poisson's ratio significantly affects the magnetism of the HEO film. The magnetic anisotropy decreases as the Poisson's ratio decreases, while coercivity increases from ∼270 to ∼1700 Oe. The axis of easy magnetization changes from in-plane to out-of-plane. These results indicate that the thickness-modulated magnetic of HEO epitaxial films has potential applications in integrating magnetic insulating oxides with spintronics. [ABSTRACT FROM AUTHOR]

Considering that CO2 reduction is mostly a multielectron reaction, it is necessary for the photocatalysts to integrate multiple catalytic sites and cooperate synergistically to achieve efficient photocatalytic CO2 reduction to various products, such as C2 hydrocarbons. Herein, through crystal engineering, we designed and constructed a metal–organic framework‐derived Zr/Ti bimetallic oxide solid solution support, which was confirmed by X‐ray diffraction, electron microscopy and X‐ray absorption spectroscopy. After anchoring Au nanoparticles, the composite photocatalyst exhibited excellent performances toward photocatalytic CO2 reduction to syngas (H2 and CO production rates of 271.6 and 260.6 μmol g−1 h−1) and even C2 hydrocarbons (C2H4 and C2H6 production rates of 6.80 and 4.05 μmol g−1 h−1). According to the control experiments and theoretical calculations, the strong interaction between bimetallic oxide solid solution support and Au nanoparticles was found to be beneficial for binding intermediates and reducing CO2 reduction, highlighting the synergy effect of the catalytic system with multiple active sites. [ABSTRACT FROM AUTHOR]

Considering that CO2 reduction is mostly a multielectron reaction, it is necessary for the photocatalysts to integrate multiple catalytic sites and cooperate synergistically to achieve efficient photocatalytic CO2 reduction to various products, such as C2 hydrocarbons. Herein, through crystal engineering, we designed and constructed a metal–organic framework‐derived Zr/Ti bimetallic oxide solid solution support, which was confirmed by X‐ray diffraction, electron microscopy and X‐ray absorption spectroscopy. After anchoring Au nanoparticles, the composite photocatalyst exhibited excellent performances toward photocatalytic CO2 reduction to syngas (H2 and CO production rates of 271.6 and 260.6 μmol g−1 h−1) and even C2 hydrocarbons (C2H4 and C2H6 production rates of 6.80 and 4.05 μmol g−1 h−1). According to the control experiments and theoretical calculations, the strong interaction between bimetallic oxide solid solution support and Au nanoparticles was found to be beneficial for binding intermediates and reducing CO2 reduction, highlighting the synergy effect of the catalytic system with multiple active sites. [ABSTRACT FROM AUTHOR]

In a recent article published in Angewandte Chemie, researchers Lei Li, Qiang Xu, and their team discuss their findings on achieving efficient photocatalytic CO2 reduction. The researchers utilized crystal engineering and derivation techniques to create a metal-organic framework-derived Zr/Ti bimetallic oxide solid solution anchored with Au nanoparticles. This innovative approach resulted in the successful reduction of CO2 to syngas and C2 hydrocarbons under simulated solar light irradiation. The study highlights the importance of integrating multiple catalytic sites and cooperation between them for effective CO2 reduction. [Extracted from the article]

A Journal of the German Chemical Society AngewandteChemie www. angewandte. org International Edition 2024– 63/ 21 I. ntegrating multiple catalytic sites … … and cooperating synergistically are the keys to achieve efficient photocatalytic CO2 reduction. In their Research Article ( e202319177), Lei Li, Qiang Xu et al. report a metal- organic framework- derived Zr/ Ti bimetallic oxide solid solution anchored with Au nanoparticles through crystal engineering and derivation, achieving photocatalytic CO2 reduction to syngas and eventually C2 hydrocarbons under simulated solar light irradiation. [Extracted from the article]

Antimony with compelling features in capacity and sodiation voltage has not been literally considered for practical applications, due to the lack of scalable fabrication methods that can make antimony stable enough in cycling and more affordable than hard carbon. Herein, the synthesis of yolk–shell antimony/carbon composites from cheap source materials is introduced, which only entails common apparatuses and is not energy intensive. The reduction of antimony trioxide coated with polypyrrole (PPy) creates hollow space and gives rise to the construction of yolk–shell structures. The material cost is evaluated to be ≈$6.6 kg–1, which is much lower than the price of standard hard carbon. A sublimation–reduction mechanism is revealed by a heating experiment performed in using environmental transmission electron microscopy (TEM). From real‐time observation of the sodiation process, the feasibility of such structure designing is validated to counter expansion upon sodiation. The composite delivers a reversible capacity up to 612 mAh g–1 and exhibits excellent stability in deep cycling. The stability is correlated with the confinement of antimony inside the carbon shell. Through further characterization using cryogenic TEM, the generation of solid–electrolyte interphases on both the antimony and carbon is confirmed. [ABSTRACT FROM AUTHOR]

As exciting candidates for next‐generation energy storage, all‐solid‐state lithium batteries (ASSLBs) are highly dependent on advanced solid‐state electrolytes (SSEs). Here, using cost‐effective LaCl3 and CeCl3 lattice (UCl3‐type structure) as the host and further combined with a multiple‐cation mixed strategy, we report a series of UCl3‐type SSEs with high room‐temperature ionic conductivities over 10−3 S cm−1 and good compatibility with high‐voltage oxide cathodes. The intrinsic large‐size hexagonal one‐dimensional channels and highly disordered amorphous phase induced by multi‐metal cation species are believed to trigger fast multiple ionic conductions of Li+, Na+, K+, Cu+, and Ag+. The UCl3‐type SSEs enable a stable prototype ASSLB capable of over 3000 cycles and high reversibility at −30 °C. Further exploration of the brand‐new multiple‐cation mixed chlorides is likely to lead to the development of advanced halide SSEs suitable for ASSLBs with high energy density. [ABSTRACT FROM AUTHOR]

As exciting candidates for next‐generation energy storage, all‐solid‐state lithium batteries (ASSLBs) are highly dependent on advanced solid‐state electrolytes (SSEs). Here, using cost‐effective LaCl3 and CeCl3 lattice (UCl3‐type structure) as the host and further combined with a multiple‐cation mixed strategy, we report a series of UCl3‐type SSEs with high room‐temperature ionic conductivities over 10−3 S cm−1 and good compatibility with high‐voltage oxide cathodes. The intrinsic large‐size hexagonal one‐dimensional channels and highly disordered amorphous phase induced by multi‐metal cation species are believed to trigger fast multiple ionic conductions of Li+, Na+, K+, Cu+, and Ag+. The UCl3‐type SSEs enable a stable prototype ASSLB capable of over 3000 cycles and high reversibility at −30 °C. Further exploration of the brand‐new multiple‐cation mixed chlorides is likely to lead to the development of advanced halide SSEs suitable for ASSLBs with high energy density. [ABSTRACT FROM AUTHOR]

A stable solid electrolyte interphase (SEI) layer is crucial for lithium metal anode (LMA) to survive in long‐term cycling. However, chaotic structures and chemical inhomogeneity of natural SEI make LMA suffering from exasperating dendrite growth and severe electrode pulverization, which hinder the practical application of LMAs. Here, we design a catalyst‐derived artificial SEI layer with an ordered polyamide‐lithium hydroxide (PA‐LiOH) bi‐phase structure to modulate ion transport and enable dendrite‐free Li deposition. The PA‐LiOH layer can substantially suppress the volume changes of LMA during Li plating/stripping cycles, as well as alleviate the parasitic reactions between LMA and electrolyte. The optimized LMAs demonstrate excellent stability in Li plating/stripping cycles for over 1000 hours at an ultra‐high current density of 20 mA cm−2 in Li||Li symmetric cells. A high coulombic efficiency up to 99.2 % in Li half cells in additive‐free electrolytes is achieved even after 500 cycles at a current density of 1 mA cm−2 with a capacity of 1 mAh cm−2. [ABSTRACT FROM AUTHOR]

A stable solid electrolyte interphase (SEI) layer is crucial for lithium metal anode (LMA) to survive in long‐term cycling. However, chaotic structures and chemical inhomogeneity of natural SEI make LMA suffering from exasperating dendrite growth and severe electrode pulverization, which hinder the practical application of LMAs. Here, we design a catalyst‐derived artificial SEI layer with an ordered polyamide‐lithium hydroxide (PA‐LiOH) bi‐phase structure to modulate ion transport and enable dendrite‐free Li deposition. The PA‐LiOH layer can substantially suppress the volume changes of LMA during Li plating/stripping cycles, as well as alleviate the parasitic reactions between LMA and electrolyte. The optimized LMAs demonstrate excellent stability in Li plating/stripping cycles for over 1000 hours at an ultra‐high current density of 20 mA cm−2 in Li||Li symmetric cells. A high coulombic efficiency up to 99.2 % in Li half cells in additive‐free electrolytes is achieved even after 500 cycles at a current density of 1 mA cm−2 with a capacity of 1 mAh cm−2. [ABSTRACT FROM AUTHOR]

Solid-state lithium metal batteries (SSLMBs) are a promising candidate for next-generation energy storage systems due to their intrinsic safety and high energy density. However, they still suffer from poor interfacial stability, which can incur high interfacial resistance and insufficient cycle lifespan. Herein, a novel poly(vinylidene fluoride-hexafuoropropylene)-based polymer electrolyte (PPE) with LiBF4 and propylene carbonate plasticizer is developed, which has a high room-temperature ionic conductivity up to 1.15 × 10-3 S cm-1 and excellent interfacial stability. Benefitting from the stable interphase, the PPE-based symmetric cell can operate for over 1000 h. By virtue of cryogenic transmission electron microscopy (Cryo-TEM) characterization, the high interfacial compatibility between Li metal anode and PPE is revealed. The solid electrolyte interphase is made up of an amorphous outer layer that can keep intimate contact with PPE and an inner Li2O-dominated layer that can protect Li from continuous side reactions during battery cycling. A LiF-rich transition layer is also discovered in the region of PPE close to Li metal anode. The feasibility of investigating interphases in polymer-based solid-state batteries via Cryo-TEM techniques is demonstrated, which can be widely employed in future to rationalize the correlation between solid-state electrolytes and battery performance from ultrafine interfacial structures. [ABSTRACT FROM AUTHOR]

The electronic band structure of MoS2 exerts far‐ranging effects on the applications of these materials, ranging from chemical catalysis, electronic, and magnetic behaviors. However, the underlying relationship between the electronic band structure and activity is largely unknown in heterogeneous catalysis including the hydrogen evolution reaction, partly due to the lack of a controllable methodology to achieve desirable electronic band structures in the 2H‐phase MoS2. Herein it is demonstrated that dual dopants can engineer the band structure of MoS2 by substituting into the adjacent Mo sites. Specifically, these constructed PdRe dimers bridged by sulfur (PdSRe sites) introduce conducting electronic states around the Fermi level to increase the metallic characteristics of MoS2, resulting in metallic‐like behavior, which is initially semiconducting. Furthermore, the efficacy of inducing a phase conversion from 2H to metallic 1T is higher for codoping with dual dopants as compared to that for the use of a single dopant, thereby generating more intrinsically active PdS*Mo sites to further increase active sites density. Ultimately, this leads to the MoS2 catalyst showing a low overpotential of 46 mV at a current density of 10 mA cm−2 and a high exchange current density of 1.524 mA cm−2, along with superior operating durability. [ABSTRACT FROM AUTHOR]

Most P2‐type layered oxides exhibit a large volume change when they are charged into high voltage, and it further leads to bad structural stability. In fact, high voltage is not the reason which causes the irreversible phase transition. There are two internal factors which affect structural evolution: the amount and distribution of Na ions retained in the lattice. Hereon, a series of layered oxides Na2/3MnxNix−1/3Co4/3−2xO2 (1/3≤x≤2/3) were synthesized. It is observed that different components have different structural evolutions during the charge/discharge processes, and further researches find that the distribution of Na ions in layers is the main factor. By controlling the distribution of Na ions, the phase transition process can be well controlled. As the referential component, P2‐Na2/3Mn1/2Ni1/6Co1/3O2 cathode with uniform distribution of Na ions is cycled at the voltage window of 1.5–4.5 V, which exhibits a volume change as low as 1.9 %. Such a low strain is beneficial for cycling stability. The current work provides a new and effective route to regulate the structural evolution of the promising P2‐type layered cathode for sodium ion batteries. [ABSTRACT FROM AUTHOR]

Most P2‐type layered oxides exhibit a large volume change when they are charged into high voltage, and it further leads to bad structural stability. In fact, high voltage is not the reason which causes the irreversible phase transition. There are two internal factors which affect structural evolution: the amount and distribution of Na ions retained in the lattice. Hereon, a series of layered oxides Na2/3MnxNix−1/3Co4/3−2xO2 (1/3≤x≤2/3) were synthesized. It is observed that different components have different structural evolutions during the charge/discharge processes, and further researches find that the distribution of Na ions in layers is the main factor. By controlling the distribution of Na ions, the phase transition process can be well controlled. As the referential component, P2‐Na2/3Mn1/2Ni1/6Co1/3O2 cathode with uniform distribution of Na ions is cycled at the voltage window of 1.5–4.5 V, which exhibits a volume change as low as 1.9 %. Such a low strain is beneficial for cycling stability. The current work provides a new and effective route to regulate the structural evolution of the promising P2‐type layered cathode for sodium ion batteries. [ABSTRACT FROM AUTHOR]

• The structure of isolated Pt and Fe single atoms anchored on nitrogen-doped carbon is firstly prepared. • The PtFeNC delivers a high half-wave potential of 0.895 V for ORR. • The primary ZAB based on PtFeNC exhibits a high energy density of 807 mA h/g at 10 mA/cm2. Fabrication of Pt-based electrocatalysts with high activity and excellent durability is critical for the practical applications into zinc-air battery (ZAB). In this work. A novel strategy for the encapsulation of Pt species into the cavities of Fe-doped zeolite imidazolate framework is proposed to increase the density of active metal atoms and improve the activity effectively, where both isolated Pt and Fe single atoms anchored on nitrogen-doped carbon (PtFeNC) are obtained by a simple pyrolysis. Impressively, PtFeNC delivers a half-wave potential of 0.895 V (vs. RHE), Moreover, PtFeNC exhibits a lower yield of peroxide species than FeNC. Importantly, the ZAB battery shows a specific capacity of as high as 807 mA h/g at a discharge current density of 10 mA/cm2. Our findings show that dual- and multi- metallic single atom catalysts with abundant active sites can be achieved to boost electrocatalytic activity for their practical applications in energy storage though the new tactic. [ABSTRACT FROM AUTHOR]