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Anionic redox chemistry can surpass theoretical limits of conventional layered oxide cathodes in energy density. A recent model system of sodium-ion batteries, O3-NaLi 1/3 Mn 2/3 O 2 , demonstrated full anionic redox capacity but is limited in reversibility and kinetics due to irreversible structural rearrangement and oxygen loss. Solutions to these issues are missing due to the challenging synthesis. Here, we harness the unique structural richness of sodium layered oxides and realize a controlled ratio of P2 structural intergrowth in this model compound with the overall composition maintained. The resulted O3 with 27 % P2 intergrowth structure delivers an excellent initial Coulombic efficiency of 87 %, comparable to the state-of-the-art Li-rich NMCs. This improvement is attributed to the effective suppression of irreversible oxygen release and structural changes, evidenced by operando Differential Electrochemical Mass Spectroscopy and X-ray Diffraction. The as-prepared intergrowth material, based on the environmentally benign Mn, exhibits a reversible capacity of 226 mAh g -1 at C/20 rate with excellent cycling stability stemming from the redox reactions of oxygen and manganese. Our work isolates the role of P2 structural intergrowth and thereby introduces a novel strategy to enhance the reversibility and kinetics of anionic redox reactions in sodium layered cathodes without compromising capacity., (© 2024 Wiley-VCH GmbH.)

Anionic redox allows the direct formation of O─O bonds from lattice oxygens and provides higher catalytic in the oxygen evolution reaction (OER) than does the conventional metal ion mechanism. While previous theories have predicted and experiments have suggested the possible O─O bond, it has not yet been directly observed in the OER process. In this study, operando soft X-ray absorption spectroscopy (sXAS) at the O K-edge and the operando Raman spectra is performed on layered double CoFe hydroxides (LDHs) after intercalation with [Cr(C 2 O 4 ) 3 ] 3- , and revealed a three-step oxidation process, staring from Co 2+ to Co 3+ , further to Co 4+ (3d6L), and ultimately leading to the formation of O─O bonds and O 2 evolution above a threshold voltage (1.4 V). In contrast, a gradual oxidation of Fe is observed in CoFe LDHs. The OER activity exhibits a significant enhancement, with the overpotential decreasing from 300 to 248 mV at 10 mA cm -2 , following the intercalation of [Cr(C 2 O 4 ) 3 ] 3- into CoFe LDHs, underscoring a crucial role of anionic redox in facilitating water splitting., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

Li-rich Mn-based layered oxides (LLO) hold great promise as cathode materials for lithium-ion batteries (LIBs) due to their unique oxygen redox (OR) chemistry, which enables additional capacity. However, the LLOs face challenges related to the instability of their OR process due to the weak transition metal (TM)-oxygen bond, leading to oxygen loss and irreversible phase transition that results in severe capacity and voltage decay. Herein, a synergistic electronic regulation strategy of surface and interior structures to enhance oxygen stability is proposed. In the interior of the materials, the local electrons around TM and O atoms may be delocalized by surrounding Mo atoms, facilitating the formation of stronger TM─O bonds at high voltages. Besides, on the surface, the highly reactive O atoms with lone pairs of electrons are passivated by additional TM atoms, which provides a more stable TM─O framework. Hence, this strategy stabilizes the oxygen and hinders TM migration, which enhances the reversibility in structural evolution, leading to increased capacity and voltage retention. This work presents an efficient approach to enhance the performance of LLOs through surface-to-interior electronic structure modulation, while also contributing to a deeper understanding of their redox reaction., (© 2024 The Authors. Advanced Science published by Wiley‐VCH GmbH.)

X-ray circular dichroism, arising from the contrast in X-ray absorption between opposite photon helicities, serves as a spectroscopic tool to measure the magnetization of ferromagnetic materials and identify the handedness of chiral crystals. Antiferromagnets with crystallographic chirality typically lack X-ray magnetic circular dichroism because of time-reversal symmetry, yet exhibit weak X-ray natural circular dichroism. Here, the observation of giant natural circular dichroism in the Ni L 3 -edge X-ray absorption of Ni 3 TeO 6 is reported, a polar and chiral antiferromagnet with effective time-reversal symmetry. To unravel this intriguing phenomenon, a phenomenological model is proposed that classifies the movement of photons in a chiral crystal within the same symmetry class as that of a magnetic field. The coupling of X-ray polarization with the induced magnetization yields giant X-ray natural circular dichroism, revealing typical ferromagnetic behaviors allowed by the symmetry in an antiferromagnet, i.e., the altermagnetism of Ni 3 TeO 6 . The findings provide evidence for the interplay between magnetism and crystal chirality in natural optical activity. Additionally, the first example of a new class of magnetic materials exhibiting circular dichroism is established with time-reversal symmetry., (© 2024 National Synchrotron Radiation Research Center (NSRRC). Advanced Materials published by Wiley‐VCH GmbH.)

Materials with negative thermal expansion (NTE) attract significant research attention owing to their unique physical properties and promising applications. Although ferroelectric phase transitions leading to NTE are widely investigated, information on antiferroelectricity-induced NTE remains limited. In this study, single-crystal and polycrystalline Pb 2 CoMoO 6 samples are prepared at high pressure and temperature conditions. The compound crystallizes into an antiferroelectric Pnma orthorhombic double perovskite structure at room temperature owing to the opposite displacements dominated by Pb 2+ ions. With increasing temperature to 400 K, a structural phase transition to cubic Fm-3m paraelectric phase occurs, accompanied by a sharp volume contraction of 0.41%. This is the first report of an antiferroelectric-to-paraelectric transition-induced NTE in Pb 2 CoMoO 6 . Moreover, the compound also exhibits remarkable NTE with an average volumetric coefficient of thermal expansion α V = -1.33 × 10 -5 K -1 in a wide temperature range of 30-420 K. The as-prepared Pb 2 CoMoO 6 thus serves as a prototype material system for studying antiferroelectricity-induced NTE., (© 2023 Wiley-VCH GmbH.)

The rational design of novel high-performance cathode materials for sodium-ion batteries is a challenge for the development of the renewable energy sector. Here, a new sodium-deficient NASICON phosphate, namely Na 3.40 □ 0.60 Co 0.5 Fe 0.5 V(PO 4 ) 3 , demonstrating the excellent electrochemical performance is reported. The presence of Co allows a third Na + to participate in the reaction thus exhibiting a high reversible capacity of ≈155 mAh g -1 in the voltage range of 2.0-4.0 V versus Na + /Na with a reversible single-phase mechanism and a small volume shrinkage of ≈5.97% at 4.0 V. 23 Na solid-state nuclear magnetic resonance (NMR) combined with ex situ X-ray diffraction (XRD) refinements provide evidence for a preferential Na + insertion within the Na2 site. Furthermore, the enhanced sodium kinetics ascribed to Co-substitution is also confirmed in combination with electrochemical impedance spectroscopy (EIS), galvanostatic intermittent titration technique (GITT), and theoretical calculation., (© 2023 Wiley-VCH GmbH.)

Lithium difluoro(oxalato) borate (LiDFOB) has been widely investigated in lithium-ion batteries (LIBs) owing to its advantageous thermal stability and excellent aluminum passivation property. However, LiDFOB tends to suffer from severe decomposition and generate a lot of gas species (e.g., CO 2 ). Herein, a novel cyano-functionalized lithium borate salt, namely lithium difluoro(1,2-dihydroxyethane-1,1,2,2-tetracarbonitrile) borate (LiDFTCB), is innovatively synthesized as a highly oxidative-resistant salt to alleviate above dilemma. It is revealed that the LiDFTCB-based electrolyte enables LiCoO 2 /graphite cells with superior capacity retention at both room and elevated temperatures (e.g., 80 % after 600 cycles) with barely any CO 2 gas evolution. Systematic studies reveal that LiDFTCB tends to form thin and robust interfacial layers at both electrodes. This work emphasizes the crucial role of cyano-functionalized anions in improving cycle lifespan and safety of practical LIBs., (© 2023 Wiley-VCH Verlag GmbH.)

Urea oxidation reaction (UOR) with a low equilibrium potential offers a promising route to replace the oxygen evolution reaction for energy-saving hydrogen generation. However, the overpotential of the UOR is still high due to the complicated 6e - transfer process and adsorption/desorption of intermediate products. Herein, utilizing a cation exchange strategy, Ni-doped CuO nanoarrays grown on 3D Cu foam are synthesized. Notably, Ni-CuO NAs/CF requires a low potential of 1.366 V versus a reversible hydrogen electrode to drive a current density of 100 mA cm -2 , outperforming various benchmark electrocatalysts and maintaining robust stability in alkaline media. Theoretical and experimental studies reveal that Ni as the driving force center can effectively enhance the urea adsorption and stabilize CO*/NH* intermediates toward the UOR. These findings suggest a new direction for constructing nanostructures and modulating electronic structures, ultimately developing promising Cu-based electrode catalysts., (© 2022 The Authors. Advanced Science published by Wiley-VCH GmbH.)

Transition metal oxides (TMOs) as high-capacity electrodes have several drawbacks owing to their inherent poor electronic conductivity and structural instability during the multi-electron conversion reaction process. In this study, the authors use an intrinsic high-valent cation substitution approach to stabilize cation-deficient magnetite (Fe 3 O 4 ) and overcome the abovementioned issues. Herein, 5 at% of Mo 4+ -ions are incorporated into the spinel structure to substitute octahedral Fe 3+ -ions, featuring ≈1.7 at% cationic vacancies in the octahedral sites. This defective Fe 2.93 ▫ 0.017 Mo 0.053 O 4 electrode shows significant improvements in the mitigation of capacity fade and the promotion of rate performance as compared to the pristine Fe 3 O 4 . Furthermore, physical-electrochemical analyses and theoretical calculations are performed to investigate the underlying mechanisms. In Fe 2.93 ▫ 0.017 Mo 0.053 O 4 , the cationic vacancies provide active sites for storing Li + and vacancy-mediated Li + migration paths with lower energy barriers. The enlarged lattice and improved electronic conductivity induced by larger doped-Mo 4+ yield this defective oxide capable of fast lithium intercalation. This is confirmed by a combined characterization including electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), galvanostatic intermittent titration technique (GITT) and density functional theory (DFT) calculation. This study provides a valuable strategy of vacancy-mediated reaction to intrinsically modulate the defective structure in TMOs for high-performance lithium-ion batteries., (© 2022 Wiley-VCH GmbH.)

Antiferromagnetic spintronics is an emerging field of non-volatile data storage and information processing. The zero net magnetization and zero stray fields of antiferromagnetic materials eliminate interference between neighbor units, leading to high-density memory integrations. However, this invisible magnetic character at the same time also poses a great challenge in controlling and detecting magnetic states in antiferromagnets. Here, two antiferromagnetic spin states close in energy in strained BiFeO 3 thin films at room temperature are discovered. It can be reversibly switched between these two non-volatile antiferromagnetic states by a moderate magnetic field and a non-contact optical approach. Importantly, the conductivity of the areas with each antiferromagnetic textures is drastically different. It is conclusively demonstrated the capability of optical writing and electrical reading of these newly discovered bistable antiferromagnetic states in the BiFeO 3 thin films., (© 2022 Wiley-VCH GmbH.)

Oxygen evolution reaction (OER) is a key half-reaction in many electrochemical transformations, and efficient electrocatalysts are critical to improve its kinetics which is typically sluggish due to its multielectron-transfer nature. Perovskite oxides are a popular category of OER catalysts, while their activity remains insufficient under the conventional adsorbate evolution reaction scheme where scaling relations limit activity enhancement. The lattice oxygen-mediated mechanism (LOM) has been recently reported to overcome such scaling relations and boost the OER catalysis over several doped perovskite catalysts. However, direct evidence supporting the LOM participation is still very little because the doping strategy applied would introduce additional active sites that may mask the real reaction mechanism. Herein, a dopant-free, cation deficiency manipulation strategy to tailor the bulk diffusion properties of perovskites without affecting their surface properties is reported, providing a perfect platform for studying the contribution of LOM to OER catalysis. Further optimizing the A-site deficiency achieves a perovskite candidate with excellent intrinsic OER activity, which also demonstrates outstanding performance in rechargeable Zn-air batteries and water electrolyzers. These findings not only corroborate the key role of LOM in OER electrocatalysis, but also provide an effective way for the rational design of better catalyst materials for clean energy technologies., (© 2022 The Authors. Advanced Science published by Wiley-VCH GmbH.)

Half metals, in which one spin channel is conducting while the other is insulating with an energy gap, are theoretically considered to comprise 100% spin-polarized conducting electrons, and thus have promising applications in high-efficiency magnetic sensors, computer memory, magnetic recording, and so on. However, for practical applications, a high Curie temperature combined with a wide spin energy gap and large magnetization is required. Realizing such a high-performance combination is a key challenge. Herein, a novel A- and B-site ordered quadruple perovskite oxide LaCu 3 Fe 2 Re 2 O 12 with the charge format of Cu 2+ /Fe 3+ /Re 4.5+ is reported. The strong Cu 2+ (↑)Fe 3+ (↑)Re 4.5+ (↓) spin interactions lead to a ferrimagnetic Curie temperature as high as 710 K, which is the reported record in perovskite-type half metals thus far. The saturated magnetic moment determined at 300 K is 7.0 μ B f.u. -1 and further increases to 8.0 μ B f.u. -1 at 2 K. First-principles calculations reveal a half-metallic nature with a spin-down conducting band while a spin-up insulating band with a large energy gap up to 2.27 eV. The currently unprecedented realization of record Curie temperature coupling with the wide energy gap and large moment in LaCu 3 Fe 2 Re 2 O 12 opens a way for potential applications in advanced spintronic devices at/above room temperature., (© 2022 Wiley-VCH GmbH.)

The search of novel quasi-1D materials is one of the important aspects in the field of material science. Toroidal moment, the order parameter of ferrotoroidic order, can be generated by a head-to-tail configuration of magnetic moment. It has been theoretically proposed that 1D dimerized and antiferromagnetic (AFM)-like spin chain hosts ferrotoroidicity and has the toroidal moment composed of only two antiparallel spins. Here, the authors report a ferrotoroidic candidate of Ba 6 Cr 2 S 10 with such a theoretical model of spin chain. The structure consists of unique dimerized face-sharing CrS 6 octahedral chains along the c axis. An AFM-like ordering at ≈10 K breaks both space- and time-reversal symmetries and the magnetic point group of mm'2'allows three ferroic orders in Ba 6 Cr 2 S 10 : (anti)ferromagnetic, ferroelectric, and ferrotoroidic orders. Their investigation reveals that Ba 6 Cr 2 S 10 is a rare ferrotoroid ic candidate with quasi 1D spin chain, which can be considered as a starting point for the further exploration of the physics and applications of ferrotoroidicity., (© 2022 Wiley-VCH GmbH.)

Single-phase perovskite oxides that contain nonprecious metals have long been pursued as candidates for catalyzing the oxygen evolution reaction, but their catalytic activity cannot meet the requirements for practical electrochemical energy conversion technologies. Here a cation deficiency-promoted phase separation strategy to design perovskite-based composites with significantly enhanced water oxidation kinetics compared to single-phase counterparts is reported. These composites, self-assembled from perovskite precursors, comprise strongly interacting perovskite and related phases, whose structure, composition, and concentration can be accurately controlled by tailoring the stoichiometry of the precursors. The composite catalyst with optimized phase composition and concentration outperforms known perovskite oxide systems and state-of-the-art catalysts by 1-3 orders of magnitude. It is further demonstrated that the strong interfacial interaction of the composite catalysts plays a key role in promoting oxygen ionic transport to boost the lattice-oxygen participated water oxidation. These results suggest a simple and viable approach to developing high-performance, perovskite-based composite catalysts for electrochemical energy conversion., (© 2021 Wiley-VCH GmbH.)

LiCoO 2 is used as a cathode material for lithium-ion batteries, however, cationic/anodic-redox-induced unstable phase transitions, oxygen escape, and side reactions with electrolytes always occur when charging LiCoO 2 to voltages higher than 4.35 V, resulting in severe capacity fade. Reported here is Mg-pillared LiCoO 2 . Dopant Mg ions, serving as pillars in the Li-slab of LiCoO 2 , prevent slab sliding in a delithiated state, thereby suppressing unfavorable phase transitions. Moreover, the resulting Li-Mg mixing structure at the surface of Mg-pillared LiCoO 2 is beneficial for eliminating the cathode-electrolyte interphase overgrowth and phase transformation in the close-to-surface region. Mg-pillared LiCoO 2 exhibits a high capacity of 204 mAh g -1 at 0.2 C and an enhanced capacity retention of 84 % at 1.0 C over 100 cycles within the voltage window of 3.0-4.6 V. In contrast, pristine LiCoO 2 has a capacity retention of 14 % within the same voltage window., (© 2020 Wiley-VCH GmbH.)

Sluggish kinetics and poor reversibility of cathode chemistry is the major challenge for magnesium batteries to achieve high volumetric capacity. Introduction of the cuprous ion (Cu + ) as a charge carrier can decouple the magnesiation related energy storage from the cathode electrochemistry. Cu + is generated from a fast equilibrium between copper selenide electrode and Mg electrolyte during standing time, rather than in the electrochemical process. A reversible chemical magnesiation/de-magnesiation can be driven by this solid/liquid equilibrium. During a typical discharge process, Cu + is reduced to Cu and drives the equilibrium to promote the magnesiation process. The reversible Cu to Cu + redox promotes the recharge process. This novel Cu + mediated cathode chemistry of Mg battery leads to a high reversible areal capacity of 12.5 mAh cm -2 with high mass loading (49.1 mg cm -2 ) of the electrode. 80 % capacity retention can be achieved for 200 cycles after a conditioning process., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Perovskite-based oxides have emerged as promising oxygen evolution reaction (OER) electrocatalysts. The performance is closely related to the lattice, electronic, and defect structure of the oxides, which determine surface and bulk properties and consequent catalytic activity and durability. Further, interfacial interactions between phases in a nanocomposite may affect bulk transportation and surface adsorption properties in a similar manner to phase doping except without solubility limits. Herein, we report the development of a single/double perovskite nanohybrid with limited surface self-reconstruction capability as an OER electrocatalyst. Such superior performance arises from a structure that maintains high crystallinity post OER catalysis, in addition to forming an amorphous layer following the self-reconstruction of a single perovskite structure during the OER process. In situ X-ray absorption near edge structure spectroscopy and high-resolution synchrotron-based X-ray diffraction reveal an amorphization process in the hybrid single/double perovskite oxide system that is limited in comparison to single perovskite amorphization, ensuring high catalytic activity., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The oxygen evolution reaction (OER) is pivotal in multiple gas-involved energy conversion technologies, such as water splitting, rechargeable metal-air batteries, and CO 2 /N 2 electrolysis. Emerging anion-redox chemistry provides exciting opportunities for boosting catalytic activity, and thus mastering lattice-oxygen activation of metal oxides and identifying the origins are crucial for the development of advanced catalysts. Here, a strategy to activate surface lattice-oxygen sites for OER catalysis via constructing a Ruddlesden-Popper/perovskite hybrid, which is prepared by a facile one-pot self-assembly method, is developed. As a proof-of-concept, the unique hybrid catalyst (RP/P-LSCF) consists of a dominated Ruddlesden-Popper phase LaSr 3 Co 1.5 Fe 1.5 O 10-δ (RP-LSCF) and second perovskite phase La 0.25 Sr 0.75 Co 0.5 Fe 0.5 O 3-δ (P-LSCF), displaying exceptional OER activity. The RP/P-LSCF achieves 10 mA cm -2 at a low overpotential of only 324 mV in 0.1 m KOH, surpassing the benchmark RuO 2 and various state-of-the-art metal oxides ever reported for OER, while showing significantly higher activity and stability than single RP-LSCF oxide. The high catalytic performance for RP/P-LSCF is attributed to the strong metal-oxygen covalency and high oxygen-ion diffusion rate resulting from the phase mixture, which likely triggers the surface lattice-oxygen activation to participate in OER. The success of Ruddlesden-Popper/perovskite hybrid construction creates a new direction to design advanced catalysts for various energy applications., (© 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Developing efficient and low-cost electrocatalysts for the oxygen evolution reaction (OER) is of paramount importance to many chemical and energy transformation technologies. The diversity and flexibility of metal oxides offer numerous degrees of freedom for enhancing catalytic activity by tailoring their physicochemical properties, but the active site of current metal oxides for OER is still limited to either metal ions or lattice oxygen. Here, a new complex oxide with unique hexagonal structure consisting of one honeycomb-like network, Ba 4 Sr 4 (Co 0.8 Fe 0.2 ) 4 O 15 (hex-BSCF), is reported, demonstrating ultrahigh OER activity because both the tetrahedral Co ions and the octahedral oxygen ions on the surface are active, as confirmed by combined X-ray absorption spectroscopy analysis and theoretical calculations. The bulk hex-BSCF material synthesized by the facile and scalable sol-gel method achieves 10 mA cm -2 at a low overpotential of only 340 mV (and small Tafel slope of 47 mV dec -1 ) in 0.1 m KOH, surpassing most metal oxides ever reported for OER, while maintaining excellent durability. This study opens up a new avenue to dramatically enhancing catalytic activity of metal oxides for other applications through rational design of structures with multiple active sites., (© 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Double perovskites have emerged as efficient candidates for catalyzing the electrochemical oxygen evolution reaction (OER). Smart control of the composition of a B-site ordered double perovskite can lead to improved catalytic performance. By adopting a facile co-doping strategy, the OER-active elements are simultaneously introduced into the B-site and B'-site of a B-site-ordered double perovskite (A 2 BB'O 6 ), leading to an enhancement of the exposed reactive sites and an optimum surface chemical state. As a result, a model system built from the substitution of Co for Mo and Fe in the Sr 2 FeMoO 6-δ double perovskite (with a composition of Sr 2 Fe 0.8 Co 0.2 Mo 0.6 Co 0.4 O 6-δ ) shows significantly enhanced OER activity in alkaline media compared with the host material, requiring an overpotential of 345 mV to reach a 10 mA cm -2 current density (catalyst loading≈0.232 mg cat  cm -2 GEO ) and a cell voltage of 1.57 V to afford the same current density for the overall water splitting when coupled with a Pt/C cathode (catalyst loading≈2 mg cm -2 ). It also demonstrates excellent electrochemical stability. The generalizability of the compositional control methodology has also been demonstrated in double perovskites incorporating transition metals other than Co (e.g., Ni)., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Rationally designing active and durable catalysts for the oxygen evolution reaction (OER) is of primary importance in water splitting. Perovskite oxides (ABO 3 ) with versatile structures and multiple physicochemical properties have triggered considerable interest in the OER. The leaching of A site cations can create nanostructures and amorphous motifs on the perovskite matrix, thus facilitating the OER process. However, selectively dissolving A site cations and simultaneously obtaining more active amorphous motifs derived from the B site cations remains a great challenge. Herein, a top-down strategy is proposed to transform bulk crystalline perovskite (LaNiO 3 ) into a nanostructured amorphous hydroxide by FeCl 3 post-treatment, resulting in an extremely low overpotential of 189 mV at 10 mA cm -2 . The top-down-constructed amorphous catalyst with a large surface area has dual NiFe active sites, where high-valence Ni 3+ -based edge-sharing octahedral frameworks are surrounded by interstitial distorted Fe octahedra and contribute to the superior OER performance. This top-down strategy provides a valid way to design novel perovskite-derived catalysts., (© 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The development of efficient bifunctional electrodes with extraordinary mass activity and robust stability is an eternal yet challenging goal for the water-splitting process. Surface reconstruction during electrocatalysis can form fresh-composition electrocatalysts with unusual amorphous phases in situ, which are more active but difficult to prepare by conventional methods. Here, a facile strategy based on fast reconstruction of amorphous nanofilm precursors is proposed for exploring precious-metal-free catalysts with good electronic conductivity, ultrahigh activity, and robust stability. As a proof of concept, an amorphous SrCo 0.85 Fe 0.1 P 0.05 O 3- δ (SCFP) nanofilm precursor with weak chemical bonds deposited onto a conductive nickel foam (NF) substrate (SCFP-NF) is synthesized by utilizing a high-energy argon plasma to break the strong chemical bonds in a crystalline SCFP target. The quickly reconstructed SCFP-NF bifunctional catalysts show ultrahigh mass activity of up to 1000 mA mg -1 at an overpotential of 550 mV and extremely long operational stability of up to 650 h at 10 mA cm -2 , significantly overperforming state-of-the-art precious-metal catalysts. Such a strategy is further demonstrated to be a universal method, which can be applied to accelerate the reconstruction of other material systems to obtain various efficient electrocatalysts., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A novel artificially created MnO 2 monolayer system is demonstrated in atomically controlled epitaxial perovskite heterostructures. With careful design of different electrostatic boundary conditions, a magnetic transition as well as a metal-insulator transition of the MnO 2 monolayer is unveiled, providing a fundamental understanding of dimensionality-confined strongly correlated electron systems and a direction to design new electronic devices., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Epitaxial core-shell CoO-CoFe2 O4 nanocrystals are fabricated by using pulsed laser deposition with the aid of melted material (Bi2 O3 ) addition and suitable lattice mismatch provided by substrates (SrTiO3 ). Well aligned orientations among nanocrystals and reversible core-shell sequence reveal tunable magnetic anisotropy. The interfacial coupling between core and shell further engineers the nanocrystal functionality., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A new way to induce a large magnetoresistance has been achieved by self-assembled nanostructures consisting of ferromagnetic spinel CoFe₂O₄ (CFO) and metallic perovskite SrRuO₃ (SRO). The interdiffused Fe³⁺ ions in SRO have paved the way to strong magnetic couplings with CFO nanopillars, resulting in the suppression of spin-polarized electron scattering., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Hybrid nanoparticles (NPs) composed of multiple components offer new opportunities for next-generation materials. In this study, a paradigm for the noble metal/ternary complex oxide hybrid NPs is reported by adopting pulsed laser ablation in liquids. As model hybrids, gold-spinel heterodimer (Au-CoFe2O4) and gold-pervoskite heterodimer (Au-SrTiO3) NPs are investigated. This work has demonstrated the diverse playgroup of NP conjugation enlarged by complex oxides., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)