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Near infrared (NIR) phosphors have been booming as promising candidates for agriculture due to the adjustable spectrum and excellent match with the dyes of the plants. Here, Mn4+ activated double perovskite LaMg 2/3 Mn 1/3 O 3 NIR phosphor was prepared, which showed high match with the absorption spectra of phytochrome P FR. Concentration of Mg2+ was decreased to create octahedron vacancy into the lattice to improve the luminescence performance. Structure and luminescence variation of the phosphors LaMg 2/3- x Nb 1/3 O 3 :Mn4+ along with the increased vacancy concentration were carried out. Relative sensitivity S r of the optimized LaMg 0.57 Nb 0.33 O 3 :Mn4+ reaches 3.109 % and exhibits great application potential in temperature sensor. Both the NIR light emitting diode (LED) and white LED were fabricated by using this double perovskite NIR phosphor and applied to the cultivation of dragon fruit as light compensation. The dragon fruits matured faster than those without any light compensation. These results confirm the great application potential of this double perovskite NIR phosphor in temperature sensor and plant cultivation. [ABSTRACT FROM AUTHOR]

[Display omitted] Transition metal chalcogenides (TMCs) hold great potential for sodium-ion batteries (SIBs) owing to their multielectron conversion reactions, yet face challenges of poor intrinsic conductivity, sluggish diffusion kinetics, severe phase transitions, and structural collapse during cycling. Herein, a self-templating strategy is proposed for the synthesis of a class of metal cobalt-doped NiSe nanoparticles confined within three-dimensional (3D) N -doped macroporous carbon matrix nanohybrids (Co-NiSe/NMC). The cation defect engineering within the developed Co-NiSe and 3D N -doped carbon plays a crucial role in enhancing intrinsic conductivity, reinforcing structural stability, and reducing the barrier to sodium ion diffusion, which are verified by a series of electrochemical kinetic analyses and density functional theory calculations. Significantly, such cation defect engineering not only reduces overpotential but also accelerates conversion reaction kinetics, ensuring both exceptional high-rate capability and extended durability. Consequently, the optimally engineered Co-NiSe/NMC demonstrates a remarkable rate performance, delivering 390 mAh g−1 at 10 A g−1. Moreover, it exhibits an unprecedented lifespan, maintaining a remarkable capacity of 403 mAh g−1 after 1400 cycles and 318 mAh g−1 after 4000 cycles, even at high rates of 1.0 and 2.0 A g−1, respectively. This work marks a substantial advancement in achieving both high performance and prolonged cycle life in sodium-ion batteries. [ABSTRACT FROM AUTHOR]

Mn-based heterostructure catalysts show great potential for catalytic oxidation of toluene. Here we fabricated a Mn-based catalyst with controlled Mn–O strength from a LaMnO 3 perovskite parent, the surficial structure of which was optimized via defect engineering by joint modification of Ce substitution and acid etching. The findings displayed that after introduction of Ce, a Mn 3 O 4 /Ce 6 O 11 hybrid was in situ formed inside LaMnO 3 structure owing to the incompatibility of Ce atoms, and the etching of acid resulted in the exposure of Mn 3 O 4 /Ce 6 O 11 hybrid by exfoliating the surficial structure. The reconstruction of catalyst structure and dismutation of Mn species was conductive to forming more lattice defects and Mn– O –Ce active sites, thereby harmonizing Mn–O strength. Furthermore, the fabricated catalyst exhibited a suitable Mn2+/Mn4+ ratio and more oxygen vacancies, which inferred easy-release of lattice oxygen and improved oxygen adsorption-activation capacity, therefore synergistically contributed to the highest performance (T 90 = 259 °C) of toluene oxidation. [Display omitted] [ABSTRACT FROM AUTHOR]

Heat dissipation and ultra-low mechanical loss are important characteristics of advanced miniaturized and intelligent electronic devices. Herein, novel 0.86PZT-0.05PMS-0.09PMT + x mol%Al 2 O 3 piezoelectric ceramics were prepared by solid-phase sintering method. The properties and structural variations of the resulting ceramics were systematically investigated by various analytical techniques. The results suggested excellent comprehensive performances of ceramics obtained at x = 0.6 mol%, with d 33 = 340 pC/N, k p = 0.507, Q m = 2117, T C = 249.8 °C, and ε r = 1473. The properties of the ceramics can be optimized by different defect dipoles induced by different Al3+ ion contents occupying the A -site and B -site. In addition, the promotion of domain changes within the lattice and the introduction of polar nano-regions by doping ions, decreased the lowering and redistribution of energy barriers. Overall, the excellent performance and ultra-high Q m of the proposed ceramics look promising for future construction of miniaturized devices. [ABSTRACT FROM AUTHOR]

Ammonia (NH3) is a crucial industrial raw material, but the traditional Haber-Bosch process is energy-intensive and highly polluting. Electrochemical methods for synthesizing ammonia using nitric oxide (NO) as a precursor offer the advantages of operating under ambient conditions and achieving both NO reduction and resource utilization. Defect engineering enhances electrocatalytic performance by modulating electronic structures and coordination environments. In this brief review, the catalytic reaction mechanism of electrocatalytic NO reduction to NH3 is elucidated, with a focus on synthesis strategies involving vacancy defects and doping defects. From this perspective, the latest advances in various catalytic reduction systems for nitric oxide reduction reaction (NORR) are summarized and synthesized. Finally, the research prospects for NO reduction to NH3 are discussed. [ABSTRACT FROM AUTHOR]

Ammonia (NH3) is a crucial industrial raw material, but the traditional Haber-Bosch process is energy-intensive and highly polluting. Electrochemical methods for synthesizing ammonia using nitric oxide (NO) as a precursor offer the advantages of operating under ambient conditions and achieving both NO reduction and resource utilization. Defect engineering enhances electrocatalytic performance by modulating electronic structures and coordination environments. In this brief review, the catalytic reaction mechanism of electrocatalytic NO reduction to NH3 is elucidated, with a focus on synthesis strategies involving vacancy defects and doping defects. From this perspective, the latest advances in various catalytic reduction systems for nitric oxide reduction reaction (NORR) are summarized and synthesized. Finally, the research prospects for NO reduction to NH3 are discussed. [ABSTRACT FROM AUTHOR]

Ammonia (NH3) is a crucial industrial raw material, but the traditional Haber-Bosch process is energy-intensive and highly polluting. Electrochemical methods for synthesizing ammonia using nitric oxide (NO) as a precursor offer the advantages of operating under ambient conditions and achieving both NO reduction and resource utilization. Defect engineering enhances electrocatalytic performance by modulating electronic structures and coordination environments. In this brief review, the catalytic reaction mechanism of electrocatalytic NO reduction to NH3 is elucidated, with a focus on synthesis strategies involving vacancy defects and doping defects. From this perspective, the latest advances in various catalytic reduction systems for nitric oxide reduction reaction (NORR) are summarized and synthesized. Finally, the research prospects for NO reduction to NH3 are discussed. [ABSTRACT FROM AUTHOR]

Ammonia (NH3) is a crucial industrial raw material, but the traditional Haber-Bosch process is energy-intensive and highly polluting. Electrochemical methods for synthesizing ammonia using nitric oxide (NO) as a precursor offer the advantages of operating under ambient conditions and achieving both NO reduction and resource utilization. Defect engineering enhances electrocatalytic performance by modulating electronic structures and coordination environments. In this brief review, the catalytic reaction mechanism of electrocatalytic NO reduction to NH3 is elucidated, with a focus on synthesis strategies involving vacancy defects and doping defects. From this perspective, the latest advances in various catalytic reduction systems for nitric oxide reduction reaction (NORR) are summarized and synthesized. Finally, the research prospects for NO reduction to NH3 are discussed. [ABSTRACT FROM AUTHOR]

Cation deficiency tuning is a central issue in thin‐film epitaxy of functional metal oxides, as it is typically more difficult than anion deficiency tuning, as anions can be readily supplied from gas sources. Here, highly effective internal deficiency compensation of Ru cations is demonstrated for Ca2RuO4 epitaxial films based on diffusive transfer of metal cations in the A2BO4 Ruddlesden–Popper lattice from solid‐phase cation sources. Through detailed structural characterization of Ca2RuO4/LaAlO3 (001) thin films grown with external cation sources by solid‐phase epitaxy, the occurrence of intercalation‐like, interstitial diffusion of La cations (from the substrates) in the A2BO4 structure is revealed, and that of Ru cations is also suggested. Relying on the interstitial‐type diffusion, an optimized Ru deficiency compensation method, which does not induce the formation of Can+1RunO3n+1 Ruddlesden–Popper impurity phases with higher n, is proposed for Ca2RuO4 epitaxial films. In the Ca2RuO4/LaAlO3 (001) thin films grown with Ru deficiency compensation, record‐high resistivity values (102–10−1 Ω cm) and a large (more than 200 K) increase in the temperature range of the nonlinear transport properties are demonstrated by transport measurements, demonstrating the possible advantages of this method in the control of the current‐induced quantum phase transition of Ca2RuO4. [ABSTRACT FROM AUTHOR]

The magnetic properties of van der Waals materials are profoundly influenced by structural defects. The layered antiferromagnet MnPS3 offers a unique opportunity to explore defect‐related magnetism, as Mn2+ vacancies can be generated by the intercalation of specific guest molecules. However, the effectiveness of this process in atomically thin flakes and the extent of the magnetic tunability remain unclear. Here, it is shown that the magnetic properties of MnPS3 can be tailored through the intercalation of different guest molecules. Notably, the insertion of four alkylammonium ions introduces different populations of Mn2+ vacancies, leading to a transition from the pristine antiferromagnetic state to more complex magnetic textures, including a ferrimagnetic state displaying a magnetic saturation of 1 µB per atom. Moreover, it is shown that the intercalation of few‐nm‐thick flakes also leads to the emergence of a ferrimagnetic response. This in‐flake intercalation, which can be monitored in real time using optical microscopy, can be interrupted before completion, generating lateral heterostructures between pristine and intercalated areas. This approach opens the way to the use of partial intercalation to define regions with distinct magnetic properties within a single flake. [ABSTRACT FROM AUTHOR]

Metal selenides (MSes) have great potential as candidate anode materials in high‐specific‐energy sodium‐ion batteries (SIBs) but are plagued by rapid capacity degradation and slow kinetics. Here, it is reveal that the Bi2Se3 anode discharge process involves multiple‐types of sodium polyselenides (Na‐pSex) which suffer from terrible dissolution and shuttling properties. Based on these observations, a nanoflower‐like composite of dual carbon‐confined Bi2Se3−x crystallites is designed via facile defect chemistry. The robust dual N‐doped carbon layer suppresses the precipitation and aggregation of Bi2Se3, significantly alleviating the dissolution and shuttle effect of Na‐pSex. Theoretical calculations indicate that the pyridine/pyrrole nitrogen sites exhibit strong van der Waals resistance and chemisorption properties against Na2Se4 and Na2Se2. Furthermore, the abundant Se vacancies improve the inherent conductivity of Bi2Se3, reduce the diffusion barrier of Na+, and accelerate the reaction kinetics. Consequently, the resulting Bi2Se3−x@DNC electrode exhibits extraordinary durability (over 2000 cycles at 10.0 A g−1) and high‐rate capability (354.4 mAh g−1 at 75.0 A g−1), propelling the battery performance to new heights. Encouragingly, the assembled hybrid capacitor displays competitive rate performance and an ultra‐long lifespan exceeding 40 000 cycles, making the Bi2Se3−x@DNC electrode a promising candidate for SIBs. [ABSTRACT FROM AUTHOR]

The investigations of polar topological conformations have become one of the hotspots due to their multitudinous physical properties and potential applications in emerging electronic devices. However, constructing polar topologies in bulk form is exceedingly challenging. In this study, bubble domains with different polar topologies, including flux-closure and half-closure, are successfully achieved in Cu-doped (K,Na)(Nb,Ta)O 3 single crystals by elaborately adjusting the phase structure and defect dipoles. The coexistence of orthorhombic and tetragonal phases results in a flattened free energy landscape, while the presence of a high concentration of defect dipoles in local regions leads to the generation of the strong internal electric field, further modifying the energy profile. The interplay of various types of energies gives rise to the smooth rotation of the polar vectors, facilitating the formation of topological structures. These findings provide a practical method for constructing topological bubble domains in bulk materials, thereby enriching the understanding of the physical properties arising from topological structures. [ABSTRACT FROM AUTHOR]

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The electrosynthesis of hydrogen peroxide (H2O2) via two‐electron oxygen reduction reaction (2e−‐ORR) enables high energy utilization and distributed H2O2 production. Rational catalyst design is essential for achieving efficient H2O2 production, in which fluorine‐modified carbon materials hold great potential. However, conventional methods can only induce limited loading of fluorine atoms in carbon‐based catalysts, leading to unsatisfying electrochemical performance. Herein, the design of fluorine‐containing active sites with high density and high 2e−‐ORR selectivity is achieved by loading fluorine‐containing chained polytetrafluoroethylene precursors onto conductive carbon substrates by plasma‐assisted ball milling technique. Consequently, the defect‐rich PTFE@CNTs show a high selectivity of over 95% and a high H2O2 yield of more than 35 mol g−1 h−1. Furthermore, the electrochemical production of H2O2 can be readily integrated with water purification units to decompose contaminants, showing over 80% degradation of multiple dyes within 1 h and over 95% removal ratio of antibiotics within 4 h. In addition, 100% sterilization of staphylococcus aureus is achieved by on‐site accumulating H2O2 in commercial saline for only 30 min. This defect engineering strategy through plasma ball milling provides a promising and universal avenue toward designing highly active and efficient electrocatalysts for 2e−‐ORR as well as other electrochemical processes. [ABSTRACT FROM AUTHOR]

Dispersion of single atoms (SAs) in the host is important for optimizing catalytic activity. Herein, we propose a novel strategy to tune oxygen vacancies in CeO2−X directionally anchoring the single atom platinum (PtSA), which is uniformly dispersed on the rGO. The catalyst's performance for the hydrogen evolution reaction (HER) can be enhanced by controlling different densities of CeO2‐X in rGO. The PtSA performs best optimally densified and loaded on homogeneous and moderately densified CeO2‐X/rGO (PtSA−M−CeO2−X/rGO). It exhibited higher activity in HER with an overpotential of 25 mV at 0.5 M H2SO4 and 33 mV at 1 KOH than that of almost reported electrocatalysts. Furthermore, it exhibited stability for 90 hours at −100 mA cm−2 in 1 KOH and −150 mA cm−2 in 0.5 M H2SO4 conditions, respectively. Through comprehensive experiments and theoretical calculations, the suitable dispersion density of PtSA on the defects of CeO2−X with more active sites gives the potential for practical applications. This research paves the way for developing single‐atom catalysts with exceptional catalytic activity and stability, holding promise in advanced green energy conversion through defects engineering. [ABSTRACT FROM AUTHOR]

In advancing aqueous zinc‐ion batteries (AZIBs) toward commercial viability, vanadium (V)‐based cathodes are pivotal, offering broad redox ranges, and compatibility with water's electrochemical limits. Despite their great potentials, V‐based cathodes face challenges in transitioning from lab to commercialization. Defect engineering is exploited as a pivotal technique that endows the cathodes with unexpected physical and chemical properties to break the intrinsic bottleneck and, in turn, enhance their electrochemical performances. This review delves into the role of defect engineering on V‐based materials, underscoring its potential in mitigating the critical challenges. It starts by encapsulating the current characteristics of V‐based cathodes in AZIBs. Research efforts related to various defects, such as oxygen vacancies, cation vacancies, cationic doping, anionic doping, water intercalation, and lattice disorders/amorphization, are then rationalized and discussed. The fabrication and characterization techniques of defect engineering are also summarized. By integrating the conclusions from existing works and tailoring defect engineering strategies, a few perspectives are provided for systematically employing defect engineering to pave the way for a more efficient transition of these promising materials from laboratory breakthroughs to commercially viable energy storage solutions. [ABSTRACT FROM AUTHOR]

Doping–dedoping chemistry lays the cornerstone for converting heteroatom dopants into intrinsic defects as the emerging active sites of carbon catalysts, but the defect content is yet hindered by inadequate doping efficiencies. Comprehending crucial factors behind the doping of pristine carbon and their correlation to the catalytic properties of dedoped carbon is thus of high significance. Here, the overlooked impact of native defects in pristine carbon on dopant‐mediated defect engineering of carbon catalysts is explicitly unveiled. Intact fullerene (C60), C60‐derived carbon, and carbon black in distinct pentagon/edge defect states are employed as respective precursors to undergo a nitrogen doping–dedoping treatment. Theoretical and experimental evidence consistently indicates that native pentagons change the preferred N doping site from the edge to the basal plane, leading to a substantially higher doping level. Importantly, in addition to pentagons from the removal of zigzag‐edged pyridinic N, N dopants in in‐plane pentagons are more easily dedoped than those in hexagons, generating even more pentagons in a new pentagon–heptagon–pentagon structure as oxygen reduction active sites. The optimized defect‐rich carbon gives an outstanding half‐wave potential of 0.834 V (0.846 V for Pt/C) via the four‐electron pathway, excellent long‐term durability, and prospective applicability in zinc–air batteries. [ABSTRACT FROM AUTHOR]

Highlights: Oxygen-vacancy-rich SiC@MoO3 nanocomposite with strong reflection loss (− 50.49 dB at 1.27 mm thickness) and broadband absorption band (8.72 GHz at 2.68 mm thickness) were constructed via in situ etching strategy. The presence of oxygen vacancy leads to an increased conductive loss and defect-induced dipole polarization, which plays significant role in attenuating the incident electromagnetic wave. Defect engineering in transition metal oxides semiconductors (TMOs) is attracting considerable interest due to its potential to enhance conductivity by intentionally introducing defects that modulate the electronic structures of the materials. However, achieving a comprehensive understanding of the relationship between micro-structures and electromagnetic wave absorption capabilities remains elusive, posing a substantial challenge to the advancement of TMOs absorbers. The current research describes a process for the deposition of a MoO3 layer onto SiC nanowires, achieved via electro-deposition followed by high-temperature calcination. Subsequently, intentional creation of oxygen vacancies within the MoO3 layer was carried out, facilitating the precise adjustment of electromagnetic properties to enhance the microwave absorption performance of the material. Remarkably, the SiC@MO-t4 sample exhibited an excellent minimum reflection loss of − 50.49 dB at a matching thickness of 1.27 mm. Furthermore, the SiC@MO-t6 sample exhibited an effective absorption bandwidth of 8.72 GHz with a thickness of 2.81 mm, comprehensively covering the entire Ku band. These results not only highlight the pivotal role of defect engineering in the nuanced adjustment of electromagnetic properties but also provide valuable insight for the application of defect engineering methods in broadening the spectrum of electromagnetic wave absor ption effectiveness. SiC@MO-t samples with varying concentrations of oxygen vacancies were prepared through in-situ etching of the SiC@MoO3 nanocomposite. The presence of oxygen vacancies plays a crucial role in adjusting the band gap and local electron distribution, which in turn enhances conductivity loss and induced polarization loss capacity. This finding reveals a novel strategy for improving the absorption properties of electromagnetic waves through defect engineering. [ABSTRACT FROM AUTHOR]

Significant interest has emerged for the application of Pd-In2O3 catalysts as high-performance catalysts for CO2 hydrogenation to CH3OH. However, precise active site control in these catalysts and understanding their reaction mechanisms remain major challenges. In this investigation, a series of Pd-InOx catalysts were synthesized, revealing three distinct types of active sites: In-O, Pd-O(H)-In, and Pd2In3. Lower Pd loadings exhibited Pd-O(H)-In sites, while higher loadings resulted in Pd2In3 intermetallic compounds. These variations impacted catalytic performance, with Pd-O(H)-In catalysts showing heightened activity at lower temperatures due to the enhanced CO2 adsorption and H2 activation, and Pd2In3 catalysts performing better at elevated temperatures due to the further enhanced H2 activation. In situ DRIFTS studies revealed an alteration in key intermediates from *HCOO over In-O bonds to *COOH over Pd-O(H)-In and Pd2In3 sites, leading to a shift in the main reaction pathway transition and product distribution. Our findings underscore the importance of active site engineering for optimizing catalytic performance and offer valuable insights for the rational design of efficient CO2 conversion catalysts. [ABSTRACT FROM AUTHOR]

Photocatalytic solar‐to‐fuel conversion over metal halide perovskites (MHPs) has recently attracted much attention, while the roles of defects in MHPs are still under debate. Specifically, the mainstream viewpoint is that the defects are detrimental to photocatalytic performance, while some recent studies show that certain types of defects contribute to photoactivity enhancement. However, a systematic summary of why it is contradictory and how the defects in MHPs affect photocatalytic performance is still lacking. In this review, the innovative roles of defects in MHP photocatalysts are highlighted. First, the origins of defects in MHPs are elaborated, followed by clarifying certain benefits of defects in photocatalysts including optical absorption, charge dynamics, and surface reaction. Afterward, the recent progress on defect‐related MHP photocatalysis, i.e., CO2 reduction, H2 generation, pollutant degradation, and organic synthesis is systematically discussed and critically appraised, putting emphasis on their beneficial effects. With defects offering peculiar sets of merits and demerits, the personal opinion on the ongoing challenges is concluded and outlining potentially promising opportunities for engineering defects on MHP photocatalysts. This critical review is anticipated to offer a better understanding of the MHP defects and spur some inspiration for designing efficient MHP photocatalysts. [ABSTRACT FROM AUTHOR]

The urea oxidation reaction (UOR), requiring less energy to produce hydrogen, is considered as a potential alternative to the traditional oxygen evolution reaction. Consequently, developing highly efficient UOR catalysts to facilitate H2 production has garnered widespread attention. A promising approach to enhancing the effectiveness of these electrocatalysts is defect engineering. By introducing structural defects, defect engineering can expose more active sites and optimize their electronic structure, thereby improving their activity. This work offers a comprehensive overview of recent progress in defect engineering of nickel-based electrocatalysts for the UOR. It summarizes various strategies for generating defects, including the creation of vacancies, doping, the incorporation of single atoms, amorphization, and achieving high refractivity. Furthermore, we discuss the advanced characterization techniques commonly used to identify the presence of defects in these electrocatalysts, as well as to determine their detailed structures. Finally, we outline the prospects and challenges associated with the systematic design and fabrication of novel UOR electrocatalysts with tunable defects, aiming to further enhance their efficiency and stability. [ABSTRACT FROM AUTHOR]

Defect engineering is an emerging technology for tailoring nanomaterials' characteristics and catalytic performance in various applications. Recently, defect‐engineered nanoparticles have emerged as highly researched materials in catalytic applications because of their exceptional redox reaction capabilities and physicochemical and optical properties. The properties of nanomaterials can be readily adjusted by controlling the nature and concentration of defects within the nanoparticles, avoiding the need for intricate design strategies. This review investigates defect engineering in nanocatalysts, including the design, fabrication, and applications. Initially, the various categories and strategies of nanomaterial defects and their impacts on the nanocatalysts' electronic and surface properties, catalytic activity, selectivity, and stability are summarized. Then, the catalytic processes and their uses, including gas sensing, hydrogen (H2) evolutions, water splitting, reductions of carbon dioxide (CO2) and nitrogen to value‐aided products, pollutant degradation, and biomedical (oncotherapy, antibacterial and wound healing, and biomolecular sensing) applications are discussed. Finally, the limitations in defect engineering and the prospective paths for allowing the logical design and optimization of nanocatalytic materials for long‐term and efficient applications are also examined. This comprehensive review gives unique insights into the current state of defect engineering in nanocatalysts and inspires future research on exploiting shortcomings to improve and customize catalytic performance. [ABSTRACT FROM AUTHOR]

Nickel-based sulfides have been proven to be excellent oxygen evolution reaction (OER) electrocatalysts due to their excellent electrical conductivity, but their poor stability hinders their application in practical applications. To address this issue, defect engineering has been proposed as a viable strategy to enhance the electronic structure of the catalyst and further boost the OER performance. Herein, a MOF-derived Sn-doped NiS/Ni3S2 nanostructure grown in situ on nickel foam (Sn–NixSy/NF) has been designed as an active OER electrocatalyst. The morphology of the material was significantly impacted by the addition of the Sn elements, nanorods modified with nanoparticles providing more active sites. Moreover, the introduction of Sn elements induced the generation of sulfur vacancies (Vs), enhanced electron transfer, promoted electron redistribution, and increased the charge transfer rate. All of these endow the Sn–NixSy/NF-T with exceptionally low overpotentials of 104 and 286 mV to achieve a current density of 10 and 100 mA cm–2 for OER. Moreover, the Sn–NixSy/NF-T showed long-term stability, maintaining 100 h at current densities of 100 mA cm–2. In short, this work opened a route for engineering defects to boost the OER. [ABSTRACT FROM AUTHOR]

Rational modulation of surface reconstruction in the oxygen evolution reaction (OER) utilizing defect engineering to form efficient catalytic activity centers is a topical interest in the field of catalysis. The introduction of point defects has been demonstrated to be an effective strategy to regulate the electronic configuration of electrocatalysts, but the influence of more complex planar defects (e.g., twins and stacking faults), on their intrinsic activity is still not fully understood. This study harnesses ultrasonic cavitation for rapid and controlled introduction of different types of defects in the FeCoNi/FeAl2O4 hybrid coating, optimizing OER catalytic activity. Theoretical calculations and experiments demonstrate that the different defects optimize the coordination environment and facilitate the activation of surface reconstruction into true catalytic activity centers at lower potentials. Moreover, it demonstrates exceptional durability, maintaining stable oxygen production at a high current density of 300 mA cm−2 for over 120 hours. This work not only presents a novel pathway for designing advanced electrocatalysts but also deepens our understanding of defect‐engineered catalytic mechanisms, showcasing the potential for rapid and efficient enhancement of electrocatalytic performance. [ABSTRACT FROM AUTHOR]

The electrostrain properties of bismuth ferrite–barium titanate (BF–BT)‐based ceramics can be well regulated; however, this often occurs at the cost of piezoelectricity, and their electrostrain‐temperature stability is poor. To address these problems, defect engineering has been utilized to enhance the comprehensive properties via the unequal substitution of Na+. In this study, 0.69BiFeO3–0.3BaTiO3–0.01NaxNbO3 (BF–BT–NxN) (x = 0.8, 0.9, 1, 1.1, and 1.2) ceramics with different defect concentrations were prepared. Enhanced piezoelectricity and electrostrain (d33 = 165 pC/N and S = ∼0.22%, respectively) were obtained for the BF–BT–N0.9N ceramic. In particular, excellent temperature stability with a strain variation of only 12% from room temperature to 180°C was achieved. The introduction of NaxNbO3 reduced the degree of distortion of the oxygen octahedron, and the defects altered the local structure and heightened its disorder, leading to an enhancement in both the electrostrain and piezoelectric properties. In addition, the temperature‐dependent evolution of the oxygen octahedron structure was altered by defect engineering. A mutual compensation mechanism for the contribution of structural evolution and domain wall motion to electrostrain has been proposed to explain the excellent temperature stability. [ABSTRACT FROM AUTHOR]

Pt single atoms catalysts with precise coordination environment and high stability are expected to achieve high performance of propane dehydrogenation (PDH). In this work, an innovative synthetic strategy is proposed to construct the S-1@0.1Pt9Zn@DPS-1 nanocomposite as a highly efficient PDH catalyst. Defect engineering is applied to induce the formation of defective porous silicalite-1 (DPS-1), which is favorable for achieving the uniformly distributed ZnO nanoclusters. The ZnO nanoclusters were further served as anchoring sites to stabilize the isolated Pt atoms. The structural characterization revealed that penta-O coordinated Pt single atom coupled with ZnO nanoclusters decorated on the DPS-1. Moreover, the atomically dispersed Pt atoms with the ideal coordination environment could act as the predominant active sites for PDH process. As expected, the optimal S-1@0.1Pt9Zn@DPS-1 catalyst delivered an excellent PDH performance (propane conversion of 40.7%, propylene selectivity of 97.5%) and good cycling regeneration stability. This work provides a new way for improving the activity and stability of catalysts in the field of industrial catalysts. [ABSTRACT FROM AUTHOR]

Photoelectrochemical (PEC) water splitting is a promising energy conversion strategy for directly converting solar energy into green hydrogen fuel. Constructing an efficient PEC device, finding an efficient photoanode material with a suitable band gap and favorable band-edge positions is essential. Tantalum nitride (Ta3N5) meets these fundamental requirements, and its theoretical maximum solar-to-hydrogen (STH) conversion efficiency can reach 15.9%. Consequently, it has been widely applied as a photoanode material for the PEC oxygen evolution reaction (OER). However, severe bulk and interface charge recombination, along with sluggish water oxygen kinetics, seriously limits its STH conversion efficiency for PEC water splitting. Herein, this feature article briefly reviews recent advances by our research group in improving the STH conversion efficiency of the Ta3N5 photoanode using various strategies, including defect engineering, construction of a gradient band structure, interface engineering, and surface modification of self-healing OER cocatalyst. Up to now, the obtained half-cell STH efficiency has exceeded 4%, providing a solid foundation for the development of tandem PEC devices for unbiased solar-driven overall water splitting toward practical application. [ABSTRACT FROM AUTHOR]

The precise engineering of surface active sites is deemed as an efficient protocol for regulating surfaces and catalytic properties of catalysts. Defect engineering is the most feasible option to modulate the surface active sites of catalysts. Creating specific active sites on the catalyst allows precise modulation of its electronic structure and physicochemical characteristics. Here, we outlined the engineering of several types of defects, including vacancy defects, void defects, dopant-related defects, and defect-based single atomic sites. An overview of progress in fabricating structural defects on catalysts via de novo synthesis or post-synthetic modification was provided. Then, the applications of the well-designed defective catalysts in energy conversion and environmental remediation were carefully elucidated. Finally, current challenges in the precise construction of active defect sites on the catalyst and future perspectives for the development directions of precisely controlled synthesis of defective catalysts were also proposed. [ABSTRACT FROM AUTHOR]

Defect engineering has proven to be one of the most effective approaches for the design of high-performance electrocatalysts. Current methods to create defects typically follow a top-down strategy, cutting down the pristine materials into fragmented pieces with surface defects yet also heavily destroying the framework of materials that imposes restrictions on the further improvements in catalytic activity. Herein, we describe a bottom-up strategy to prepare free-standing NiFe layered double hydroxide (LDH) nanoplatelets with abundant internal defects by controlling their growth behavior in acidic conditions. Our best-performing nanoplatelets exhibited the lowest overpotential of 241 mV and the lowest Tafel slope of 43 mV/dec for the oxygen evolution reaction (OER) process, superior to the pristine LDHs and other reference cation-defective LDHs obtained by traditional etching methods. Using both material characterization and density functional theory (DFT) simulation has enabled us to develop relationships between the structure and electrochemical properties of these catalysts, suggesting that the enhanced electrocatalytic activity of nanoplatelets mainly results from their defect-abundant structure and stable layered framework with enhanced exposure of the (001) surface.

Highlights Oxygen-vacancy-rich SiC@MoO3 nanocomposite with strong reflection loss (− 50.49 dB at 1.27 mm thickness) and broadband absorption band (8.72 GHz at 2.68 mm thickness) were constructed via in situ etching strategy. The presence of oxygen vacancy leads to an increased conductive loss and defect-induced dipole polarization, which plays significant role in attenuating the incident electromagnetic wave.

Spatially-ordered MoSe 2 /CdS intimate S-scheme heterojunction was constructed, which exhibited an outstanding photocatalytic capability due to the strengthened built-in electric field via Fermi level modulation with donor (Se vacancies) and acceptor (Mo5+) impurities. [Display omitted] • Multi-armed MoSe 2 /CdS Z-scheme heterojunction with intimate Mo-S bond connection. • Se vacancies and Mo5+ serve as donor and acceptor impurities of MoSe 2. • Strengthened built-in electric field of MoSe 2 /CdS via Fermi level modulation. • Excellent HER rate (52.62 mmol·g−1·h−1) and AQE (34.8 % at 400 nm) are achieved. • Outstanding H 2 production stability confirmed by cycling and long-term tests. Spatially-ordered S-scheme photocatalysts are intriguing due to their enhanced light harvesting, spatially isolated redox sites, and strong redox abilities. Nonetheless, heightening the performance of S-scheme photocatalysts via controllable defect engineering is still challenging to now. In this work, multi-armed MoSe 2 /CdS S-scheme heterojunction with intimate Mo-S bond coupling and adjustable Se vacancies (V Se) and Mo5+ concentrations was constructed, which consisted of few- or even single-layered MoSe 2 growing on the {11–20} facets of wurtzite CdS arms. The S-scheme charge transmission mechanism of MoSe 2 /CdS heterojunction was validated by density functional theory calculation combined with in situ photo-irradiated X-ray photoelectron spectroscopy, surface photovoltage, and radical measurements. Moreover, the Fermi level gap between CdS and MoSe 2 was enlarged by regulating the contents of donor (V Se) and acceptor (Mo5+) impurities with synthesis temperature, which strengthens the built-in electric field and carriers transfer driving force of MoSe 2 /CdS composites, contributing to an outstanding H 2 evolution activity of 52.62 mmol·g−1·h−1 (corresponding to an apparent quantum efficiency of 34.8 % at 400 nm) under visible-light irradiation (λ > 400 nm), 25.8 times that of Pt-loaded CdS counterpart and a substantial amount of reported CdS-containing photocatalysts. Our study results are anticipated to facilitate the rational design of advanced semiconductor nanostructures for efficient solar conversion and utilization. [ABSTRACT FROM AUTHOR]

[Display omitted] Oxygen vacancy engineering in transition metal oxides is an effective strategy for improving catalytic performance. Herein, defect-enriched Mn 2 O 3 catalysts were constructed by controlling the calcination temperature. The high content of oxygen vacancies and accompanying Mn4+ ions were generated in Mn 2 O 3 catalysts calcined at low temperature, which could greatly improve the low-temperature reducibility and migration of surface oxygen species. DFT theoretical calculations further confirmed that molecular oxygen and toluene were easily adsorbed over defective α-Mn 2 O 3 (2 2 2) facets with an energy of −0.29 and −0.48 eV, respectively, and corresponding O O bond length is stretched to 1.43 Å, resulting in the highly reactive oxygen species. Mn 2 O 3 -300 catalyst with abundant oxygen vacancies exhibited the highest specific reaction rate and lowest activation energy. Furthermore, the optimized catalyst possessed the outstanding stability, water tolerance and CO 2 yield. In comparison with the fresh Mn 2 O 3 -300 catalyst, the physical structure and surface property of the used catalyst remained almost unchanged regardless of whether undergoing the stability test at consecutive catalytic runs as well as high temperature, and water resistance test. In situ DRIFTS spectra further elucidated that introducing the water vapor had little effect on the reaction intermediates, indicating the excellent durability of the defect-enriched catalyst. [ABSTRACT FROM AUTHOR]

[Display omitted] Exploring precious metal-free bifunctional electrocatalysts for both the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER) is essential for the practical application of rechargeable Zn-air battery (ZAB). Herein, Ni-doped Co 9 S 8 nanoparticles embedded in a defect-rich N, S co-doped carbon matrix (d-Ni x Co 9-x S 8 @NSC) are synthesized via a facile pyrolysis and acid treatment process. The introduction of abundant defects in both the carbon matrix and metal sulfide provides numerous active sites and significantly enhances the electrocatalytic performances for both the ORR and OER. d-Ni x Co 9-x S 8 @NSC exhibits a superior half-wave potential of 0.841 V vs. RHE for the ORR and delivers a low overpotential of 0.329 V at 10 mA cm−2 for the OER. Additionally, Zn-air secondary battery using d-Ni x Co 9-x S 8 @NSC as the air cathode displays a higher specific capacity of 734 mAh g Zn −1 and a peak power density of 148.03 mW cm−2 compared to those of state-of-the-art Pt/C-RuO 2 (673 mAh g Zn −1 and 136.9 mW cm−2, respectively). These findings underscore the potential of d-Ni x Co 9-x S 8 @NSC as a high-performance electrocatalyst for secondary ZABs, offering new perspectives on the design of efficient noble metal-free electrocatalysts for future energy storage and conversion applications. [ABSTRACT FROM AUTHOR]

BaTiO 3 -based ceramic is considered to be a fascinating dielectric material with high reliability for ultra-thin multilayer ceramic capacitors (MLCC). Here, we fabricated a series of acceptor-doped BaTiO 3 (Mg: 0.2, 0.5, 1.0, 1.5, 2.0, and 5.0 mol%) ceramics with Al 2 O 3 and SiO 2 as sintering additives. With an increase in Mg concentration, the insulation resistance of the BaTi 1- x Mg x O 3 ceramics initially increases and then decreases, in which the 0.5 mol% Mg-doped ceramic achieves superior degradation behavior. The reason is that with the incorporation of the acceptor ion Mg2+, the charge compensation mechanism in the system changes. Initially, barium vacancy is generated, which is gradually dominated by oxygen vacancy. Analysis indicates that the segregation of the acceptor state barium vacancy to the grain boundary increases the schottky barrier of the grain boundary, while the gradual increase of the donor state oxygen vacancy reduces the reliability of the ceramic. This study provides a comprehensive overview illustrating the significant role of point defects in the potential barrier of the grain boundary in acceptor-doped BaTiO 3 ceramics. It identifies a pathway to achieve high reliability in BaTiO 3 -based MLCC. [ABSTRACT FROM AUTHOR]

A series of new x (y ZnO/Al 2 O 3)-(1- x)Ba 0·5 Sr 0·5 TiO 3 (x = 10, 20, 50 wt%, y = 1, 1.3, 1.5 mol) ceramics were prepared by solid-phase method. The effects of ion diffusion and compound effect on the lattice vibration and dielectric properties of Ba 0·5 Sr 0·5 TiO 3 were studied. When ZnO and Al 2 O 3 are equimolar, the two react to form ZnAl 2 O 4. Under the composite effect, the dielectric permittivity of Ba 0·5 Sr 0·5 TiO 3 is effectively reduced, T c moves to high temperature, and the tunability gradually increases. When ZnO is in excess, T c remains basically unchanged, proving the unique role of the spinel structure. Because ZnO can fully diffuse into Ba 0·5 Sr 0·5 TiO 3 , extremely high tunability is achieved through defect engineering. 50 wt% (ZnO/Al 2 O 3)-50 wt%Ba 0·5 Sr 0·5 TiO 3 achieved excellent microwave dielectric properties, with dielectric permittivity, tunability and Q value of 201, 23.6 % and 368, respectively. In addition, ZnAl 2 O 4 –Ba 0.5 Sr 0·5 TiO 3 composite ceramics were successfully prepared by directly compounding Ba 0·5 Sr 0·5 TiO 3 with oxides, which greatly reduced energy loss. [ABSTRACT FROM AUTHOR]

The large piezoelectric coefficient (d 33) and high mechanical quality factor (Q m) are essential for piezoelectric ceramics used in high-power devices. It is pity that the two parameters are usually opposite, with higher d 33 corresponding to lower Q m. In order to well-balance the d 33 and Q m , the rare-earth element Ce with multi-valence was introduced into the 0.06 Pb(Sc 1/2 Nb 1/2)O 3 -0.61 Pb(Mg 1/3 Nb 2/3)O 3 -0.33PbTiO 3 (x Ce-PSN-PMN-PT) ceramics in this work. The structure, electrical properties and optical properties of ceramics were systematically analyzed. Optimal electrical performances (d 33 = 719 pC/N, Q m = 256, and dielectric loss tan δ = 0.007) were obtained in 0.02Ce-PSN-PMN-PT ceramics. These excellent performances originate from the multiscale coordination effects among defect dipoles, local structural heterogeneity, domain structure, phase structure, and grain size. The x Ce-PSN-PMN-PT ceramics exhibit excellent photoluminescence properties in the blue wavelength range. Our research provides a new paradigm for deep-sea electro-optical communication. [ABSTRACT FROM AUTHOR]

5-Hydroxymethylfurfural (HMF), serving as a versatile platform compound bridging biomass resource and the fine chemicals industry, holds significant importance in biomass conversion processes. The electrooxidation of HMF plays a crucial role in yielding the valuable product (2,5-furandicarboxylic acid), which finds important applications in antimicrobial agents, pharmaceutical intermediates, polyester synthesis, and so on. Defect engineering stands as one of the most effective strategies for precisely synthesizing electrocatalytic materials, which could tune the electronic structure and coordination environment, and further altering the adsorption energy of HMF intermediate species, consequently increasing the kinetics of HMF electrooxidation. Thereinto, the most routine and effective defect are the anionic vacancies and cationic vacancies. In this concise review, the catalytic reaction mechanism for selective HMF oxidation is first elucidated, with a focus on the synthesis strategies involving both anionic and cationic vacancies. Recent advancements in various catalytic oxidation systems for HMF are summarized and synthesized from this perspective. Finally, the future research prospects for selective HMF oxidation are discussed. [ABSTRACT FROM AUTHOR]

Manipulating thermal properties of materials can be interpreted as the control of how vibrations of atoms (known as phonons) scatter in a crystal lattice. Compared to a perfect crystal, crystalline solids with defects are expected to have shorter phonon mean free paths caused by point defect scattering, leading to lower lattice thermal conductivities than those without defects. While this is true in many cases, alloying can increase the phonon mean free path in the Cd‐doped AgSnSbSe3 system to increase the lattice thermal conductivity from 0.65 to 1.05 W m−1 K−1 by replacing 18% of the Sb sites with Cd. It is found that the presence of lone pair electrons leads to the off‐centering of cations from the centrosymmetric position of a cubic lattice. X‐ray pair distribution function analysis reveals that this structural distortion is relieved when the electronic configuration of the dopant element cannot produce lone pair electrons. Furthermore, a decrease in the Grüneisen parameter with doping is experimentally confirmed, establishing a relationship between the stereochemical activity of lone pair electrons and the lattice anharmonicity. The observed "harmonic" behavior with doping suggests that lone pair electrons must be preserved to effectively suppress phonon transport in these systems. [ABSTRACT FROM AUTHOR]

To evaluate and diversify, control methods for surface defects in photocatalysts have surged because of their significant effect on carrier dynamics and reactivity. Sulfide photocatalysts, wherein anion defects act as electron traps, are not as extensively researched as oxide photocatalysts, and therefore, the knowledge of defects remains incomplete. Herein, simple treatments such as grinding, alkali immersion, and annealing are used to introduce surface defects into CdS, which is a representative sulfide photocatalyst. Moreover, Pt‐loaded CdS is prepared by reducing Pt ions using electrons trapped in the defects. The amount of defects on the CdS surface is successfully estimated by quantifying the amount of unreacted Pt ions through the absorbance of the reaction solution. The results indicate that the defect density can be increased using any of these employed methods. The surface state varies with the introduction method, leading to significant changes in photocatalytic activity. Grinding induces particle refinement and amorphization, alkali immersion induces oxidation and hydroxylation, and annealing enables the formation of a sulfurized surface. These surface conditions degrade the photocatalytic activity, and therefore, introduction of defects under relatively mild conditions is preferred. Herein, the sample calcined at 473 K shows the highest photocatalytic activity. [ABSTRACT FROM AUTHOR]

Understanding the nature, density, and distribution of structural defects is crucial for tailoring the properties of atomically thin two‐dimensional (2D) materials, which is paramount for advances in nanotechnology. Ion irradiation emerges as a promising technique for defect engineering of single‐atom‐thick materials, due to its high controllability, repeatability, and accuracy. The objective is to provide a comprehensive review elucidating the impact of various irradiation parameters, such as ion mass, energy, fluence, and incident angle, on defect formation in 2D materials. However, the presence of the substrate can significantly influence defect yield and the mechanism of formation due to backscattered ions and sputtered substrate atoms. Hence, a thorough comparison of ion beam‐induced defects in both freestanding (suspended) and supported (on a substrate) 2D materials, with a focus on substrate effects is conducted. Moreover, a detailed analysis of characterization techniques suitable for each scenario will be provided. This work not only contributes to advancing the current understanding of defect formation and evolution in 2D materials during ion beam irradiation but also offers insights into selecting specific parameters for this process to create desired defects in these materials. Consequently, it has the potential to facilitate the design of nanoscale devices with tailored functionality. [ABSTRACT FROM AUTHOR]

Hexagonal MAB phases （h‐MAB） have attracted attention due to their potential to exfoliate into MBenes, similar to MXenes, which are predicted to be promising for Li‐ion battery applications. However, the high cost of synthesizing MBenes poses challenges for their use in batteries. This study presents a novel approach where a simple ball‐milling treatment is employed to enhance the purity of the h‐MAB phase Ti2InB2 and introduce significant indium defects, resulting in improved conductivity and the creation of abundant active sites. The synthesized Ti2InB2 with indium defects (VIn‐Ti2InB2) exhibits excellent electrochemical properties, particularly exceptional long‐cycle stability at current densities of 5 A g−1 (5000 cycles, average capacity decay of 0.0018%) and 10 A g−1 (15 000 cycles, average capacity decay of 0.093%). The charge storage mechanism of VIn‐Ti2InB2, involving a dual redox reaction, is proposed, where defects promote the In‐Li alloy reaction and a redox reaction with Li in the TiB layer. Finally, a Li‐ion full cell demonstrates cycling stability at 0.5 A g−1 after 350 cycles. This work presents the first accessible and scalable application of VIn‐Ti2InB2 as a Li‐ion anode, unlocking a wealth of possibilities for sustainable electrochemical applications of h‐MAB phases. [ABSTRACT FROM AUTHOR]

This study investigates the effect of defect engineering on the catalytic activity of a NiPS3 monolayer catalyst for the hydrogen evolution reaction (HER). Three different types of vacancies on the basal plane of the monolayer are explored through a multi-step mechanism involving the dissociative adsorption of a water molecule and subsequent electrochemical adsorption of the dissociated proton. Co-formation of vacancies in both Ni and S sites is found to be the most effective in enhancing the catalytic performance of the monolayer. A key resource for the reaction thermodynamics is the S-substitution-like physisorption of a water molecule on a vacant S site, followed by the dissociative occupation of OH and H into vacant sites of S and Ni elements, boosted by the NiS di-vacancy configuration with low activation energy barriers. Investigation reveals the highest contribution of bonding orbitals to the monolayer-H bond makes it the most desirable defect engineering approach for transition metal phosphorus chalcogenides with high HER activities. Overall, this study highlights the significance of controlled defect engineering in augmenting the catalytic performance of NiPS3 monolayer catalysts for HER. [ABSTRACT FROM AUTHOR]

Powered by optical energy, photocatalytic reduction for fuel production promises to be an ideal long-term solution to a number of key energy challenges. Photocatalysts with enhanced light absorption, fast electron/hole separation rates, and exposed activity sites are essential to improve photocatalytic efficiency. Semiconductors are constrained by their own intrinsic properties and have limited performance in photocatalysis, but defect engineering provides an opportunity to modulate the physical and chemical properties of semiconductors. Defect engineering has been shown to be effective in regulating electron distribution and accelerating photocatalytic kinetics during photocatalysis. This review introduces the definition and categorization of defects, then explains the main effects of defect engineering on photoabsorption, carrier separation/migration, and surface reduction reactions. We then review the milestones in the design of defect-engineered photocatalysts for key chemical reactions, including hydrogen evolution, CO2 reduction, and N2 reduction, and tabulate their respective effects on catalytic performance. Finally, we provide insights and perspectives on the challenges and potential of defect engineering for photoreduction reactions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Facile synthesis of structurally engineered Ternary Spinel-type NiFeCoO 4 nanoparticles. • Ni-Fe-Co elements work synergistically to enhance the electrocatalytic activity. • The defect engineered NiFeCoO 4 requires a low water splitting cell voltage of 1.67 V. Transition metal spinel oxides were engineered with active elements as bifunctional water splitting electrocatalysts to deliver superior intrinsic activity, stability, and improved conductivity to support green hydrogen production. In this study, we reported the ternary metal Ni-Fe-Co spinel oxide electrocatalysts prepared by defect engineering strategy with rich and deficient Na+ ions, termed NFCO-Na and NFCO, which suggest the formation of defects with Na+ forming tensile strain. The Na-rich NiFeCoO 4 spinel oxide reveals lattice expansion, resulting in the formation of a defective crystal structure, suggesting higher electrocatalytic active sites. The spherical NFCO-Na electrocatalysts exhibit lower OER and HER overpotentials of 248 mV and 153 mV at 10 mA cm−2 and smaller Tafel slope values of about 78 mV dec−1 and 129 mV dec−1, respectively. Notably, the bifunctional NFCO-Na electrocatalyst requires a minimum cell voltage of about 1.67 V to drive a current density of 10 mA cm−2. The present work highlights the significant electrochemical activity of defect-engineered ternary metal oxides, which can be further upgraded as highly active electrocatalysts for water splitting applications. [ABSTRACT FROM AUTHOR]

High‐performance and durable membranes are being sought to enable energy‐efficient CO2 capture. Although representing an appealing candidate for the above application, successful translation of distinct properties of MOF filler into hybrid composite membranes (HCMs) remains challenging. In this study, we synthesized uniform hollow defect‐engineered UiO‐66 nanoparticles as filler for enhancing the CO2/N2 separation performance and durability of Pebax‐2533 membranes. The existence of missing‐linker defects in the framework not only endows HCMs with higher CO2/N2 adsorption selectivity but also provides ultrafast CO2 transport pathways; moreover, hollow structure of UiO‐66 not only contributes to better filler dispersibility in polymeric matrix but also reduces CO2 diffusion path length. Obtained HCMs manifest concurrently increased CO2 permeability (3100 Barrer) and CO2/N2 separation factor (44), far exceeding state‐of‐the‐art 2019 upper bound for polymer membranes; moreover, our membranes exhibit enhanced resistance toward plasticization, physical aging, and water vapors under harsh operation conditions. [ABSTRACT FROM AUTHOR]

Electrocatalytic water splitting seems to be an efficient strategy to deal with increasingly serious environmental problems and energy crises but still suffers from the lack of stable and efficient electrocatalysts. Designing practical electrocatalysts by introducing defect engineering, such as hybrid structure, surface vacancies, functional modification, and structural distortions, is proven to be a dependable solution for fabricating electrocatalysts with high catalytic activities, robust stability, and good practicability. This review is an overview of some relevant reports about the effects of defect engineering on the electrocatalytic water splitting performance of electrocatalysts. In detail, the types of defects, the preparation and characterization methods, and catalytic performances of electrocatalysts are presented, emphasizing the effects of the introduced defects on the electronic structures of electrocatalysts and the optimization of the intermediates' adsorption energy throughout the review. Finally, the existing challenges and personal perspectives of possible strategies for enhancing the catalytic performances of electrocatalysts are proposed. An in‐depth understanding of the effects of defect engineering on the catalytic performance of electrocatalysts will light the way to design high‐efficiency electrocatalysts for water splitting and other possible applications. [ABSTRACT FROM AUTHOR]

In this study, S-CCO@Co(OH)2 ('CCO' representing CuCo2O4/Cu2O; 'S-'representing sulfur doping) was synthesized by hydrothermal method followed by electrodeposition. The multiple effects of S doping were studied by S doping and constructing 3D core–shell structure. S doping induced the reduction of Cu2+ and Co3+ to Cu+ and Co2+, respectively. Also, S partially replaces O and creates oxygen vacancies, which increases a number of active sites for the redox reaction enhancing the redox reaction activity. After the electrodeposition, S–Co bond is formed between the Co(OH)2 shell and the S-CCO core, which suggests a synergistic effect between S doping and core–shell structure. The formation of S–Co bond is conducive to electron and ion transport, thus improving electrochemical performance. After modification, the specific capacitance of S-CCO@Co(OH)2 is 4.28 times higher than CCO, up to 1730 Fg−1. Furthermore, the assembled S-CCO@Co(OH)2//activated carbon supercapacitor exhibits an energy density of 83.89 Whkg−1 at 848.81 Wkg−1 and a retention rate of 98.48% after 5000 charge and discharge cycles. Therefore, S doping and its mutual effect with the utilization of the core–shell structure considerably enhanced the electrochemical performance of the CCO-based electrodes, endowing its potential in further application. [ABSTRACT FROM AUTHOR]

Fast‐charging ability of sodium‐ion batteries (SIBs) is mainly determined by a highly effective redox reaction rate. However, traditional metal@carbon composites rarely achieve atom‐level dispersion at high density, resulting in poor reaction rates. Herein, supported by the introduction of carbon vacancies, abundant C─S/C─O chemical bonds are successfully established in a carbon carrier. Then, plenty of Sb single atoms (Sb SA/PC) are first anchored with a high loading of 31.4 wt%, achieving a high yield of 210.56 g per batch. Benefiting from dense Sb─O─C/Sb─S─C interfacial chemical bonds, Sb─S2O coordination configurations are firmly confined in the interior of carbon. Surprisingly, the conductivity of Sb SA/PC‐2 is approximately 2.2 × 107 times greater than that of pristine Sb2S3. Consequently, Sb SA/PC‐2 exhibits ultrahigh fast‐charging capability (201.7 mAh g−1 at 20.0 A g−1) and ultralong cycling life (364.4 mAh g−1 at 5.0 A g−1 after 5000 cycles). Theoretical calculations reveal that the fast‐charging capability can be attributed to the low migration barrier and increased number of active sites. Moreover, owing to the structural integrity of Sb single atoms, phase separation is effectively inhibited. This work is anticipated to open an avenue toward designing advanced electrode materials for ultrafast‐charging SIBs. [ABSTRACT FROM AUTHOR]