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This article mainly focuses on the most common types of high-speed railways malfunctions in overhead contact systems, namely, unstressed droppers, foreign-body invasions, and pole number-plate malfunctions, to establish a deep-network detection model. By fusing the feature maps of the shallow and deep layers in the pretraining network, global and local features of the malfunction area are combined to enhance the network's ability of identifying small objects. Further, in order to share the fully connected layers of the pretraining network and reduce the complexity of the model, Tucker tensor decomposition is used to extract features from the fused-feature map. The operation greatly reduces training time. Through the detection of images collected on the Lanxin railway line, experiments result show that the proposed multiview Faster R-CNN based on tensor decomposition had lower miss probability and higher detection accuracy for the three types faults. Compared with object-detection methods YOLOv3, SSD, and the original Faster R-CNN, the average miss probability of the improved Faster R-CNN model in this paper is decreased by 37.83%, 51.27%, and 43.79%, respectively, and average detection accuracy is increased by 3.6%, 9.75%, and 5.9%, respectively. [ABSTRACT FROM AUTHOR]

The Railway Catenary system is an integral and essential component of railway electrification. The working state of the catenary system can directly affect the normal operation of the locomotive. The section insulator (SI) in the catenary system is required for the electrical segregation of two feeds such as in a crossover while deciding the destined track from two adjacent tracks. We propose a deep learning-based approach for abnormal detection of insulator breakage in high-speed railway catenary. Semantic segmentation is an important theory in deep learning-based image segmentation. Aiming at the abnormal detection of insulator breakage in high-speed railway catenary, semantic segmentation technology is used to detect the abnormalities, which can quantitatively describe the area of insulator breakage or damage. Based on the DeepLab V3+ semantic segmentation network, the characteristics of the insulator's data are retrieved. The Multi Feature DeepLab V3+ network and the Attention DeepLab V3+ networks are proposed to solve the anomaly detection problem of the damaged area from the insulator's images. The results show that the improved two-folded semantic segmentation networks can better mark the contours of the damaged area of the insulator to safeguard the Catenary system. The outcomes are compared with the original DeepLab V3+ and the MIoU values of the two improved semantic segmentation networks have been improved to a remarkable extent that improves the overall performance of the deep learning-based segmentation of insulator's images. [ABSTRACT FROM AUTHOR]

Objective. To investigate the relationship between serum procalcitonin (PCT) levels and prognosis in children with bacterial meningitis. Methods. Eighty-two child patients were included in this prospective study. The diagnosis of meningitis was based on clinical features and cerebrospinal fluid findings. PCT levels were measured with a specific immunoluminometric assay. Results. (a) Patients with bacterial meningitis had significantly higher serum PCT than those with viral meningitis. (b) The PCT levels of patients with severe sepsis or septic shock were significantly higher than those who had no or mild sepsis. (c) PCT levels decreased significantly in patients who had good curative effect, whereas PCT levels did not changed in patients who had no curative effect. (d) The PCT levels were significantly higher in those who died than those who survived. Conclusions. Serum PCT is related to the severity of disease in children with bacterial meningitis. A fall in PCT after treatment may have favorable prognostic significance. [ABSTRACT FROM AUTHOR]

Lead-free ceramics 0.5BaCaTiO-0.5BaTiZrO- xIrO ( x = 0-1.2 %) were prepared at a low temperature of 1260 °C via sintering the as-synthesized nanoparticles, which were synthesized by a modified Pechini polymeric precursor method. All samples featured high levels of densification under the synthesis conditions; particularly, the ceramic prepared at IrO content of 0.4 % achieved the highest relative density (~97.4 %). Phase transition from tetragonal to orthorhombic and a polymorphic phase transition (PPT) region were observed, which were influenced by the IrO content. The dielectric properties, temperature coefficient of capacitance, ferroelectric properties, and piezoelectric properties as a function of IrO content were thoroughly studied. Optimal electrical properties (remnant polarization, piezoelectric constant, and planar electromechanical coupling factors, i.e., P = 6.28 μC/cm, d = 199 pC/N, and k = 0.258) were obtained around the PPT region. The findings of the ceramic electrical properties by IrO doping are believed to be insightful in the development of lead-free dielectric and ferroelectric materials. [ABSTRACT FROM AUTHOR]

Highlights: [•] The thermal stability of IrO2 films was strongly dependent on the oxygen pressure and annealing temperature. [•] The PLD-IrO2 films had a higher stability than the previous reported results. [•] The thermal stability was almost consistent with thermodynamic calculation. [•] IrO2 films were found to be stable up to 923K under oxygen pressure of 1Pa. [•] The room-temperature resistivity of IrO2 films showed a value of 49–58μΩcm at P O2 =1Pa. [ABSTRACT FROM AUTHOR]

Highlights: [•] A semiconductor laser was first used to prepare wide-area LCVD-TiC x coatings. [•] The effect of laser power for the deposition of TiC x coatings was discussed. [•] TiC x coatings showed a columnar cross section and a dense surface texture. [•] TiC x coatings had a 1–4 order lower laser density than those of previous reports. [•] This study gives the possibility of LCVD applying on the preparation of TiC x coating. [ABSTRACT FROM AUTHOR]

Abstract: Wide-area and thick titanium nitride (TiN x ) films were prepared on Al2O3 substrate by laser chemical vapor deposition (LCVD) using tetrakis (diethylamido) titanium (TDEAT) and ammonia (NH3) as source materials. Effects of laser power (P L) and pre-heating temperature (T pre) on the composition, microstructure and deposition rate of TiN x films were investigated. (111) and (200) oriented TiN x films in a single phase were obtained. The lattice parameter and N to Ti ratio of the TiN x films slightly increased with increasing P L and was close to stoichiometric at P L >150W. TiN x films had a cauliflower-like surface and columnar cross section. The deposition rate of TiN x films increased from 42 to 90µm/h at a depositing area of 10mm by 10mm substrate, decreasing with increasing P L and T pre. The highest volume deposition rate of TiN x films was about 102 to 105 times greater than those of previous LCVD using Nd:YAG laser, argon ion laser and excimer laser. [Copyright &y& Elsevier]

Abstract: Titanium nitride (TiN x ) films were prepared by laser chemical vapor deposition (LCVD) with tetrakis-diethylamido-titanium (TDEAT) and NH3 as the source materials. The effects of the fraction of ammonia () on the microstructure, preferred orientation and deposition rate were investigated. Non-oriented TiN x films with a cauliflower-like texture were obtained without NH3, whereas (111), (200) and (220) preferred TiN x films in a single phase with facetted and square textures were obtained with NH3 gas. The lattice parameter decreased slightly with increasing . The deposition rate (R dep) of TiN x films with a deposition area of about 300mm2 increased with increasing , and attained the highest value of 90μmh−1 at =0.5, laser power (P L)=100W and deposition temperature (T dep)=597°C. [Copyright &y& Elsevier]

Abstract: Iridium oxide (IrO2) thin films were prepared on Si (100) and quartz glass substrates by pulsed laser deposition (PLD) technique. Electrical and optical properties, as well as morphology of annealed IrO2 thin films in air ambient were investigated by using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), four-point probe method, and ultraviolet-visible spectrometer. The results showed that the surface morphology of IrO2 thin films became denser and compact after being annealed at 600–800°C for 30min, while the surface roughness changed little. The room-temperature electrical resistivity of IrO2 films slightly decreased after being annealed at 600–750°C and showed a minimum electrical resistivity of (38±3)μΩcm at 750°C. The average transmittance of annealed IrO2 thin films (thickness: 65nm) in the visible range was increased to almost 85–88%. [Copyright &y& Elsevier]

Abstract: Iridium (Ir) thin films, deposited on Si (100) substrate by pulsed laser deposition (PLD) technique using Ir target in a vacuum atmosphere, were annealed in air ambient and the thermal stability was investigated. The crystal structure and surface morphology of Ir thin films before and after being annealed were studied by X-ray diffraction, Raman scattering, scanning electron microscope, and atomic force microscopy. The results showed that single-phase Ir thin films with (111) preferred orientation could be deposited on Si (100) substrate at 300°C and it remained stable below 600°C, which showed a promising bottom electrode of integrated ferroelectric capacitors. Ir thin films got oxidized to IrO2 at temperatures from 650 to 800°C. [Copyright &y& Elsevier]

Abstract: Extremely smooth iridium (Ir) thin films were deposited on Si(100) substrate at lower temperature than 300°C by pulsed laser deposition (PLD) technique using Ir target in a vacuum atmosphere. The crystal orientation, surface morphology, and resistivity of the Ir thin films were systematically determined as a function of substrate temperature. Well-crystallized and single-phase Ir thin films with (111) preferred orientation were obtained at substrate temperature of 200–300°C. The surface roughness increased with the increasing of substrate temperature. Likewise, the room-temperature resistivity of Ir thin films decreased with increasing substrate temperature, showing a low value of (10.7±0.1)μΩcm at 300°C. [Copyright &y& Elsevier]

Abstract: IrO2 thin films were prepared on Si(100) substrates by laser ablation. The effect of substrate temperature (T sub) on the structure (crystal orientation and surface morphology) and property (electrical resistivity) of the laser-ablated IrO2 thin films was investigated. Well crystallized and single-phase IrO2 thin films were obtained at T sub =573–773K in an oxygen partial pressure of 20Pa. The preferred orientation of the laser-ablated IrO2 thin films changed from (200) to (110) and (101) depending on T sub. With the increasing of T sub, both the surface roughness and crystallite size increased. The room-temperature electrical resistivity of IrO2 thin films decreased with increasing T sub, showing a low value of (42±6)×10−8 Ωm at T sub =773K. [Copyright &y& Elsevier]

0.5Ba 0.9 Ca 0.1 TiO 3 –0.5BaTi 0.88 Zr 0.12 O 3 –0.12%La– x Ir 4+ ( x =0–1.25%) (BCT–BZT–La– x Ir 4+ ) ceramics were synthesized using a modified Pechini method. The effects of iridium content ( x ) on the crystal structure and electrical properties of the ceramics were studied. All samples showed a pure orthorhombic perovskite structure, and the lattice parameters decreased gradually with increasing x . The temperatures associated with the orthorhombic–tetragonal and tetragonal–cubic phase transitions were dependent on the iridium content. Ceramics doped with 0.75% Ir 4+ exhibited the highest relative permittivity and the lowest loss tangent (<1%), suggesting that iridium entered the matrix and enhanced the grain size. The diffused phase transition initially weakened, then strengthened with increasing x , indicating that the ferroelectric properties were influenced by the iridium content. The optimal electrical properties, i.e., d 33 =269 pC/N, k p =0.26, and Q m =77, were obtained at x= 0.50%. [ABSTRACT FROM AUTHOR]

Lithium–sulfur (Li–S) batteries can offer high capacity and energy‐density, but face challenges like low conductivity, lithium polysulfides (LiPSs) shuttling, and limited reaction kinetics. In this study, the electronic configuration of Mo 4d orbital in MoS2 is modulated through a one‐step method involving tungstate anion (WO42−) modulation to form a stable 1T‐MoS2/carbon composite (1T‐W‐MoS2/C). When WO42− is introduced, it causes a transfer of electrons to Mo in 2H‐MoS2, resulting in the generation of a stable 1T phase. In the composite, 1T‐MoS2 nanosheets exhibit remarkable electronic conductivity, hydrophilicity, and catalytic activity, facilitating the LiPSs adsorption and Li+ transport. Meanwhile, the WO42− modulation can create abundant adsorption/catalytic sites with defects on the basal surface and edges of MoS2, facilitating the efficient catalysis of LiPSs conversion. Furthermore, the 3D‐printed electrodes without utilization of binders and current collectors can ensure high mass loading and promote ion diffusion and electrolyte penetration. Theoretical and experimental results confirm that 1T‐W‐MoS2/C can catalyze LiPSs conversion, suppress LiPSs shuttling, and enhance sulfur reaction kinetics. Therefore, the 3D‐printed 1T‐W‐MoS2/C/S cathode exhibits a high initial capacity and excellent rate capability, achieving an areal capacity of 7.37 mAh cm−2 with a sulfur loading of 8.89 mg cm−2. [ABSTRACT FROM AUTHOR]

Zinc–air batteries (ZABs) hold significant promise for flexible electronics due to their high energy density and low cost. However, their practical application is hindered by the sluggish kinetics of the oxygen evolution and oxygen reduction reactions (OER/ORR). This study highlights a novel design of vertical graphene arrays (VGs) anchored on PrBa0.5Sr0.5Co1.8Ru0.2O5+δ (PBSCRu) perovskite nanofibers, fabricated via plasma‐enhanced chemical vapor deposition. Notably, the VG growth induces the exsolution of Co nanoparticles from the PBSCRu perovskite, resulting in a unique PBSCRu‐Co‐VG heterostructure. Theoretical calculations demonstrate that constructing PBSCRu‐Co‐VG heterojunction regulates interfacial electronic redistribution, thereby lowering energy barriers for both OER and ORR. As a result, the PBSCRu@VG‐5 electrocatalyst exhibits superior stability and higher peak power density in both liquid and flexible solid‐state ZABs compared to the pristine PBSCRu electrocatalyst. This protocol advances the integration of synergetic perovskite/metal/graphene composites, offering considerable potential for next‐generation energy conversion technologies. [ABSTRACT FROM AUTHOR]

K can reversibly intercalate into graphite by forming KC8 (279 mA h g−1, ≈0.2 V) in conventional carbonate electrolytes, but the large ionic radius of K+ (1.38 Å) easily results in structural degradation and rapid capacity decay. Here, commercial graphite particles are directly electrospun into network-like carbon fibers, thus forming a flexible Gr@CNF membrane. This hybrid electrode configuration can efficiently withstand the volume expansion during K+ insertion. K‖‖Gr@CNF half-cells can stably operate for over 800 cycles (running time of 170 days at C/3) and achieve fast K+-intercalation kinetics at 5C. The fabricated Gr@CNF‖‖AC K-ion hybrid capacitor delivers a high energy density of 119.3 W h kg−1 at 2717.82 W kg−1, corresponding to a fast-charge time of 3.2 min. [ABSTRACT FROM AUTHOR]

[Display omitted] • 3D hierarchical Z-scheme heterojunction was successfully constructed. • The sandwich-like layered structure of the ZCA composite photocatalyst offers a rich heterojunction interface. • A possible mechanism for the enhanced performance was briefly discussed by means of work function calculations. • This work provided insights into the use of natural minerals for high value-added mineral applications. Construction of hierarchical architecture with suitable band alignment for graphitic carbon nitride (g-C 3 N 4) played a pivotal role in enhancing the efficiency of photocatalysts. In this study, a novel attapulgite-intercalated g-C 3 N 4 /ZnIn 2 S 4 nanocomposite material (ZIS/CN/ATP, abbreviated as ZCA) was successfully synthesized using the freeze-drying technique, thermal polymerization, and a simple low-temperature hydrothermal method. Attapulgite (ATP) was intercalated into g-C 3 N 4 to effectively regulate its interlayer structure. The results reveal a substantial enlargement of its internal space, thereby facilitating the provision of additional active sites for improved dispersibility of ZnIn 2 S 4. Notably, the optimized photocatalyst, comprising a mass ratio of ATP, g-C 3 N 4 , and ZnIn 2 S 4 at 1:1:2.5 respectively, achieves an outstanding hydrogen evolution rate of 3906.15 μmol g−1h−1, without the need for a Pt co-catalyst. This rate surpasses that of pristine g-C 3 N 4 by a factor of 475 and ZnIn 2 S 4 by a factor of 5, representing a significant improvement in performance. This significant enhancement can be primarily attributed to the higher specific surface area, richer active sites, broadened light response range, and efficient interfacial charge transfer channels of the ZCA composite photocatalyst. Furthermore, the Z-scheme photocatalytic mechanism for the sandwich-like layered structure heterojunction was thoroughly investigated using diverse characterization techniques. This work offers new insights for enhancing photocatalytic performance through the expanded utilization of natural minerals, paving the way for future advancements in this field. [ABSTRACT FROM AUTHOR]

Photocatalytic ammonia production holds immense promise as an environmentally sustainable approach to nitrogen fixation. In this study, In2O3/In2S3-ZnCdS ternary heterostructures were successfully constructed through an innovative in situ anion exchange process, coupled with a low-temperature hydrothermal method for ZnCdS (ZCS) incorporation. The resulting In2O3/In2S3-ZCS photocatalyst was proved to be highly efficient in converting N2 to NH3 under mild conditions, eliminating the need for sacrificial agents or precious metal catalysts. Notably, the NH4+ yield of In2O3/In2S3-0.5ZCS reached a significant level of 71.2 μmol g−1 h−1, which was 10.47 times higher than that of In2O3 (6.8 μmol g−1 h−1) and 3.22 times higher than that of In2O3/In2S3 (22.1 μmol g−1 h−1). This outstanding performance can be attributed to the ternary heterojunction configuration, which significantly extends the lifetime of photogenerated carriers and enhances the spatial separation of electrons and holes. The synergistic interplay between CdZnS, In2S3, and In2O3 in the heterojunction facilitates electron transport, thereby boosting the rate of the photocatalytic nitrogen fixation reaction. Our study not only validates the efficacy of ternary heterojunctions in photocatalytic nitrogen fixation but also offers valuable insights for the design and construction of such catalysts for future applications. [ABSTRACT FROM AUTHOR]

Hard carbon (HC) has become the most promising anode material for sodium‐ion batteries (SIBs), but its plateau capacity at ≈0.1 V (Na+/Na) is still much lower than that of graphite (372 mAh g−1) in lithium‐ion batteries (LIBs). Herein, a CO2‐etching strategy is applied to generate abundant closed pores in starch‐derived hard carbon that effectively enhances Na+ plateau storage. During CO2 etching, open pores are first formed on the carbon matrix, which are in situ reorganized to closed pores through high‐temperature carbonization. This CO2‐assisted pore‐regulation strategy increases the diameter and the capacity of closed pores in HC, and simultaneously maintains the microsphere morphology (10–30 µm in diameter). The optimal HC anode exhibits a Na‐storage capacity of 487.6 mAh g−1 with a high initial Coulomb efficiency of 90.56%. A record‐high plateau capacity of 351 mAh g−1 is achieved, owing to the abundant closed micropores generated by CO2‐etching. Comprehensive in situ and ex situ tests unravel that the high Na+ storage performance originates from the pore‐filling mechanism in the closed micropores. [ABSTRACT FROM AUTHOR]

[Display omitted] The development of noble metal-based bifunctional electrocatalysts is the key to driving the sluggish oxygen reduction/evolution reaction (ORR/OER) for rechargeable zinc-air battery applications. There is an urgent need to design and construct robust and cost-efficient bifunctional electrocatalysts. Herein, an interface engineering strategy of Ruddlesden–Popper (RP) perovskite/CeO 2 /carbon heterojunction with core–shell nanostructures is described. Ce-based metal–organic framework derived CeO 2 -C nanosheets are decorated on the surface of RP type perovskite Pr 3 Sr(Ni 0.5 Co 0.5) 3 O 10−δ (PSNC) nanofibers. Benefiting from the favorable conductivity, abundant oxygen vacancies and strong interfacial coupling, the hierarchical CeO 2 -C/PSNC electrode delivers a half-wave potential of 0.78 V (ORR), and an OER overpotential of 370 mV at 10 mA cm−2, respectively. A liquid rechargeable zinc-air battery (ZAB) assembled with CeO 2 -C/PSNC electrocatalysts as the air cathode exhibits a peak power density of 161 mW cm−2 and a long-term cycling life over 219 h. In addition, the CeO 2 -C/PSNC-based all-solid-state cable-type ZAB provides a high open-circuit voltage (∼1.44 V), good flexibility and durability. Our study opens a new insight into the design of efficient electrocatalysts for rechargeable ZABs by constructing hierarchical heterojunctions. [ABSTRACT FROM AUTHOR]

Lead-free (1− x )Ba 0.90 Ca 0.10 Ti 0.95 Zr 0.05 O 3 –( x )RuO 2 ( x = 0–2.0 mol%) ceramics were prepared by conventional solid state reaction with the as-synthesized nanoparticles by a modified Pechini method, showing high densification (96.4–97.1%) with the grain size of ∼2.2 μm. Effects of RuO 2 contents on the ceramics crystal structure and electrical properties were investigated. The phase evolution was identified by X-ray powder diffraction analysis, and the coexisted Tetragonal and Rhombohedral phases were detected at x around 1.0 mol%. The formation mechanism of defect electron complexes was sated in detail. Diversified dielectric properties and ferroelectric relaxation stemmed from defect electron complexes, charge accumulation at grain boundary, long-range ferroelectric dipole order, etc. Ferroelectric properties could be optimized apparently by polarized–aged process. The optimum electrical properties, i.e. d 33 = 195 pC/N, k p = ∼0.22, and Q m = 78.9, were obtained at x = 1.0 mol%. [ABSTRACT FROM AUTHOR]

0.5Ba 0.9 Ca 0.1 TiO 3 –0.5BaTi 0.88 Zr 0.12 O 3 –0.12%La– x Er ( x = 0–0.5%) lead–free ceramics were prepared by a modified Pechini polymeric precursor method, and the effects of erbium contents ( x ) on the crystal structure, dielectric and piezoelectric properties were investigated. The samples showed high densification (relative density: ∼96.6%) with fine grain size (∼0.652 μm) under the synthesis conditions at x = 0.2%. The Curie temperature ( T C ) shifted toward lower temperature and orthorhombic–to–tetragonal phase transition temperature ( T O–T ) shifted toward higher temperature with addition of x , which was beneficial for elevating piezoelectric properties as pinched effect of the temperature. The diffuseness of the ceramics was receded with a small addition of x , because of disappeared oxygen vacancy and small area of polar nano–regions (PNRs) in the structure. The elevated piezoelectric constant ( d 33 ; ∼200 pC/N) and receded mechanical quality factor ( Q m ; ∼70) at x = 0.2% showed “softening effect” by donor doping. However, erbium showed “hardening effect” by accepter doping with the substitution of B sites in the matrix of ABO 3 structure with excessive erbium contents. [ABSTRACT FROM AUTHOR]

Amphoteric rare‐earth ion dopants can improve ferroelectric ceramic electrical performance because of their amphoteric ion radius and valences. Herein, Ho3+‐doped Ba0.90Ca0.10(Ti0.95Zr0.05)2O5 ceramics are sintered at 1230 °C with as‐synthesized nanoparticles. The effects of various holmium contents (x) on the phase, structure, dielectric, and piezoelectric characteristics are investigated. For low x (<1.5 mol%), Ho3+ occupies the Ba2+ or/and Ca2+ sites, leading to high dielectric properties due to decreased oxygen vacancies, while the electrical properties weaken with further increase in x. The ferroelectricity and piezoelectricity also deteriorate when x > 1.5 mol% because of the re‐emerged oxygen vacancies and interrupted long‐range ordering with large compositional fluctuations. The defect chemistry mechanism at different x contents is deduced in accordance with the phase and electrical properties. The activation energy initially elevates to 1.56 eV and then decreases to 1.35 eV with increasing x. Results indicate that the ceramics are promising candidates for lead‐free ferroelectric ceramics. [ABSTRACT FROM AUTHOR]

Semiconductor photocatalytic nitrogen reduction reaction (PNRR) stands as a promising clean technique for ammonia synthesis, yet it confronts numerous challenges. In this study, Ag nanoparticle-modified Cu-doped Bi 2 WO 6 (ACB) porous composite materials with varying mass percentages were successfully synthesized using a solvothermal reduction approach. The incorporation of transition metal Cu effectively modulates the energy band position of Bi 2 WO 6. Furthermore, the introduction of Ag nanoparticles significantly suppresses the recombination of photogenerated carriers. Without adding sacrificial agent, the photocatalytic nitrogen fixation yield of ACB reaches an impressive 184.93 μmol·g−1·h−1, which is 5.44 times higher than that of pristine Bi 2 WO 6. A comprehensive analysis of the experimental results reveals that the combined effect of Cu doping and Ag nanoparticle loading endows ACB with an increased exposure of active sites, thereby significantly enhancing its photocatalytic nitrogen fixation performance. This research offers a promising approach for the design of metal nanoparticle-supported catalysts for PNRR, holding significant implications for the advancement of other material systems. [Display omitted] • Ag/Cu dual-meta-functionalized porous Bi 2 WO 6 microsphere was successfully prepared. • The separation efficiency of photogenerated electron-hole pairs were significantly enhanced. • The nitrogen fixation performance for the optimal photocatalyst was 5.44 times superior to the pristine Bi 2 WO 6. • A plausible mechanism for the photocatalytic nitrogen fixation was proposed. [ABSTRACT FROM AUTHOR]

A Ti 3 C 2 T x /Ni/NiCo-PBA composite is synthesized by in-situ growing NiCo Prussian blue (PB) nanocubes on Ti 3 C 2 T x /Ni sheets, serving as an electrode for hybrid capacitive deionization. Owing to the synergistic effect of Ti 3 C 2 T x , Ni nanoparticles, and NiCo-PBA, Ti 3 C 2 T x /Ni/NiCo-PBA demonstrates excellent desalination performance. Additionally, the desalination mechanism of Ti 3 C 2 T x /Ni/NiCo-PBA is thoroughly investigated. [Display omitted] • A Ti 3 C 2 T x /Ni/NiCo-PBA composite is synthesized by growing NiCo-PBA on Ti 3 C 2 T x /Ni sheets. • The AC||Ti 3 C 2 T x /Ni/NiCo-PBA HCDI device exhibits excellent desalination performance. • The desalination mechanism of Ti 3 C 2 T x /Ni/NiCo-PBA electrode is thoroughly investigated. The design and development of high-performance electrode materials are crucial for improving the desalination efficiency of hybrid capacitive deionization (HCDI). In this study, a Ti 3 C 2 T x /Ni/NiCo-PBA composite is synthesized by in-situ growing NiCo Prussian blue (PB) nanocubes on Ti 3 C 2 T x /Ni sheets, serving as an electrode for HCDI. The Ti 3 C 2 T x sheets provide excellent conductivity and a suitable substrate for the growth of NiCo-PBA nanocubes. The Ni nanoparticles help prevent the oxidation of Ti 3 C 2 T x sheets, and provide a source of Ni for NiCo-PBA synthesis. Additionally, the NiCo-PBA nanocubes effectively inhibit re-stacking of Ti 3 C 2 T x sheets, enlarge crystal lattice spacing, and facilitate diffusion and storage of salt ions. Consequently, the AC||Ti 3 C 2 T x /Ni/NiCo-PBA HCDI device exhibits a high salt removal capacity of 36.62 mg g−1, low energy consumption of 11.14 Wh m−3, and water recovery of 61.86 %. Importantly, the AC||Ti 3 C 2 T x /Ni/NiCo-PBA device achieves a good salt removal capacity of 53.22 mg g−1 in a high concentration NaCl solution (2000 μS cm−1). After 20 cycles, the desalination capacity remains stable, and the structure of Ti 3 C 2 T x /Ni/NiCo-PBA is intact, indicating excellent cycling stability. Additionally, the desalination mechanism of Ti 3 C 2 T x /Ni/NiCo-PBA electrode is thoroughly investigated. [ABSTRACT FROM AUTHOR]

[Display omitted] Interface engineering strategy has been developed to design efficient catalysts for boosting electrocatalytic performance in past few decades. Herein, heterojunctions of PrCoO 3 /Co 3 O 4 nanocages (PCO/Co 3 O 4 NCs) with atomic-level engineered interfaces and rich oxygen vacancies are proposed for Zn-air batteries. The synthesized product shows exceptional bifunctional activity and robust stability towards oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). The enhanced catalytic capacity is primary attributed to the synergistic effect of PCO/Co 3 O 4 , evidenced by the experimental results and theoretical calculations. More importantly, the PCO/Co 3 O 4 NCs assembled liquid Zn-air battery exhibits a power density of 182 mW cm−2 and a long-term operation of 185 h. When assembled into solid-state cable type battery, this newly designed catalyst also reaches a stable open circuit voltage (1.359 V) and a peak power density of 85 mW cm−3. Our findings provide essential guidelines of engineering heterostructured electrocatalysts for future wearable electronic devices. [ABSTRACT FROM AUTHOR]

Lithium‖graphite dual-ion batteries (DIBs) have received widespread attention due to their low cost and high operating voltage (nearly 5 V). However, DIBs face several challenges such as decomposition of the electrolyte under high voltage and structural deterioration of graphite. Herein, montmorillonite (MMT) is employed to generate a favorable and robust cathode electrolyte interface (CEI) layer on the graphite surface. As a result, the DIBs exhibit a 100% capacity retention for 500 cycles at 2C. Even after 1000 cycles at 5C, the capacity retention is still as high as 99%. [ABSTRACT FROM AUTHOR]

Prussian blue analogs (PBAs) are ideal cathode materials for sodium-ion batteries (SIBs) owing to their cost-effectiveness, good low-temperature performance, and facile synthesis process. Nevertheless, their actual capacity and cycling stability limit practical application. Herein, a new chelating agent, sodium tartrate, is proposed to synthesize high-quality Fe-based Prussian blue (HQ-NFF) with enhanced Na content and a stable structure through chelation effect-assisted co-precipitation. The crystal structure of HQ-NFF undergoes a phase transition to a Na-rich monoclinic phase after full discharge, leading to improved capacity and cycling stability. The HQ-NFF cathode exhibits an ultra-high capacity of 160.8 mAh g−1 and a capacity of 146.1 mAh g−1 at 2 C, with a capacity retention of 75.3 % after 150 cycles. Moreover, a 3D-printed HQ-NFF cathode with an areal loading of 7.88 mg cm−2, delivers a high areal capacity of 0.969 mAh cm−2 and good rate capability. [Display omitted] • A high-quality Fe-based Prussian blue (HQ-NFF) is synthesized through chelation effect-assisted co-precipitation. • HQ-NFF undergoes a phase transition to a Na-rich monoclinic phase after discharge, leading to improved capacity. • A 3D-printed HQ-NFF cathode delivers a high areal capacity of 0.969 mAh cm−2 with high areal loading. [ABSTRACT FROM AUTHOR]

Capacitive deionization (CDI) is considered as one promising technique for desalination owing to its low energy consumption, high efficiency, facile operation, and non-toxicity. In a CDI device, ions are removed from solution via electro-sorption onto electrode surface and intercalation into electrode materials. The utilization of 2D materials in CDI systems has attracted significant attention because of their unique structure, high electronic conductivity, large surface area, fast ion transport kinetics, excellent ion selectivity, high ion adsorption capacity, and improved desalination efficiency. This review highlights the recent advancements of 2D materials in CDI, focusing on their morphology, CDI performance, and ion capturing mechanisms. Additionally, the challenges and future prospects of 2D materials in CDI are discussed. Overall, the integration of 2D materials in CDI shows great potential for advanced water purification technologies, providing sustainable and efficient solutions to address global water challenges and extract specific ions (e.g. , Li+) from the salty lake brine. This review discusses the recent development of 2D electrode materials in capacitive deionization. Furthermore, the challenges and perspectives of 2D electrode materials in capacitive deionization are put forward. [Display omitted] • This review highlights the recent advancements of 2D materials in CDI, focusing on their morphology, CDI performance, and ion capturing mechanisms. • 2D CDI electrodes can be used to capture Na+, Li+, Cl- and other ions. • The challenges and future prospects of 2D materials in CDI are discussed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Z-scheme TiO 2-x /Cu/ZnO heterojunction was successfully constructed. • The enhanced photocatalytic activity was due to the SPR effect and Z-scheme heterojunction. • ZnO coating nanolayer by ALD improves the antioxidant ability of Cu. • A possible mechanism for the enhanced performance was briefly discussed. Poor visible light utilization and charge separation efficiency of TiO 2 restrict its extensive application in the photocatalytic field. Herein, a specific Z-scheme TiO 2-x /Cu/ZnO heterojunction was successfully constructed by atomic layer deposition (ALD) technique and spray pyrolysis technology. Benefited from the surface plasmon resonance (SPR) effect of Cu and Z-scheme heterojunction, the visible light absorption capacity was greatly enhanced. Meanwhile, ZnO nanolayer coating, prepared by ALD technique, protects Cu element to hinder its oxidation, thus enhancing the separation efficiency of photogenerated carriers. Therefore, the photocatalytic hydrogen production performance was significant improved, exhibiting a maximum value of 342.0 µmol·g−1·h−1 for the optimal B-T-0.1C-10Z (black TiO 2 /0.1Cu/10 nm ZnO) sample without any noble-metal cocatalyst, which is higher than pure TiO 2 (310.7 µmol·g−1·h−1, with 3 wt% Pt) synthesized by spray pyrolysis method under equal conditions. In addition, a possible mechanism for the enhanced performance was briefly discussed based on the experimental results. [ABSTRACT FROM AUTHOR]

Li-S batteries suffer from limited electronic conductivity and shuttle effect of soluble LiPSs, which can hinder redox kinetics and reduce overall electrochemical performance. To solve these issues, we propose a strategy to synthesize a CoNi-layered double hydroxide/carbon composite (L-CoNi-LDH/C) through laser treatment and hydrothermal reaction. The resulting L-CoNi-LDH/C composite possesses a high specific surface area, enabling effectively anchor sulfur molecules and adsorb LiPSs. Moreover, the 2D layered structure of LDH and porous carbon framework can facilitate electron and ion transport. The Co and Ni species in the LDH structure act as catalysts, promoting the conversion of LiPSs into Li 2 S/Li 2 S 2 and enhancing redox kinetics. A Li-S battery using CoNi-LDH/C as S host (S@CoNi-LDH/C) shows an initial capacity of 1574 mAh g−1 and maintains a reversible capacity of 1097 mAh g−1 after 100 cycles. [Display omitted] • A laser-induced CoNi-LDH/C composite is employed as S host for Li-S battery. • L-CoNi-LDH/C can catalyze the conversion of LiPSs and inhibit the shuttle effect. • The S@L-CoNi-LDH/C based Li-S battery exhibits excellent electrochemical performance. [ABSTRACT FROM AUTHOR]

Capacitive deionization (CDI) has garnered significant attention as a promising solution to address the issue of freshwater scarcity. Developing novel electrodes with high salt removal capacity and good stability is crucial for the high-performance CDI devices. In this study, Ti 3 AlC 2 is employed as a precursor to prepare Ti 3 C 2 T x /Ni composite for the CDI anode and cathode using the molten salt etching method. The Ti 3 C 2 T x /Ni composite exhibits a well-preserved accordion-like morphology of Ti 3 C 2 T x , with Ni nanoparticles uniformly distributed on the surface and between layers. The Ti 3 C 2 T x /Ni composite possesses a large interlayer spacing and high specific surface area, which can effectively trap Cl− and Na+ ions. Moreover, the Ti 3 C 2 T x /Ni interface can improve electronic conductivity and enhance ion transport. As a result, the Ti 3 C 2 T x /NiǁTi 3 C 2 T x /Ni CDI symmetry device exhibits a salt removal capacity of 49.4 mg g−1 in a 500 μS cm−1 NaCl solution at an applied voltage of 1.2 V with a removal rate of 3.00 mg g−1 min−1. After 30 cycles, the Ti 3 C 2 T x surface remains unoxidized, and the salt removal capacity increases, indicating that the surface functional groups (−Cl and −O) and Ni nanoparticles can alleviate oxidation and facilitate the cycle stability of the Ti 3 C 2 T x /Ni composites. • A Ti 3 C 2 T x /Ni composite is synthesized using the molten salt etching method. • The Ti 3 C 2 T x /Ni composite is used as anode and cathode of the CDI device. • The Ti 3 C 2 T x /NiǁTi 3 C 2 T x /Ni CDI device exhibits a salt removal capacity of 49.4 mg g−1. [ABSTRACT FROM AUTHOR]

Metal‐ion capacitors are being widely studied to reach a balance between power and energy output by combining the merits of conventional batteries and capacitors. The main challenge for Na‐ion capacitors is that the battery‐type anode usually has unsatisfactory power density and long‐term stability since most Na host materials have a poor kinetic and structural stability. Herein, asymmetric hollow bowl‐like carbon (HBC) materials are rationally designed and fabricated through an in situ hard‐template approach. The formation originates from a subtle control of capillary force and the mechanical strength of the carbon shell. The HBCs possess abundant mesopores, high volumes of accessible surface area as well as an open macropore network. As a 3D host, MoSe2 nanocrystals are anchored onto the HBC matrix by a solid‐phase reaction. The obtained MoSe2@HBC nanobowl electrode exhibits pseudocapacitive sodium storage with fast kinetics, improved capacity at high currents, and cycle stability, which is also supported by DFT calculations. Sodium ion capacitor full cells are fabricated using the two bowl‐like architectures (MoSe2@HBC as the anode and HBC as the cathode), which deliver high energy and power densities, long cycle life, and a comparably low self‐discharge rate. Moreover, application of the HBC in a zinc‐ion capacitor (ZIC) is also demonstrated. [ABSTRACT FROM AUTHOR]

Co-doping of piezoelectric ceramics by amphoteric rare earth ions has resulted in synergistic improvement of their electrical properties. In this study, Yb3+ and Dy3+ co-doped lead-free 0.5BaTi 0.8 Zr 0.2 O 3 -0.5Ba 0.7 Ca 0.3 TiO 3 nanoparticles and ceramics were prepared. The synthetic process of the nanoparticles by a modified Pechini polymeric precursor method was studied by FT-IR, TG-DSC, HRTEM, XRD, and Raman spectroscopy. The densified (>96%) ceramics were obtained by sintering the as-synthesised nanoparticles at 1220 °C, and the influence of Yb content (x) on the phase structure, permittivity, ferroelectricity, piezoelectricity, and thermophysical performances was studied. Initially, for low x , Yb3+ occupied A sites in the perovskite structure as donor dopants, resulting in improved ferroelectric and piezoelectric properties and decreased domain switching activation energy with few oxygen vacancies; while the electrical properties deteriorated as x increased further. The relationships of the defect dipole-induced electrical properties or/and activation energy with internal stress, structure distortions, and impurity phase were deduced. The optimum piezoelectric coefficient (d 33 * = 683 p.m./V) with the lowest domain switching activation energy (E a = 0.233 eV) was determined at x = 0.60 mol%, indicating that the ceramics were suitable for practical applications. [ABSTRACT FROM AUTHOR]

• MoSSe nanosheets grown on N-doped carbon hollow spheres (MoSSe/NC) are employed as s hosts. • MoSSe/NC can catalyze the conversion of LiPSs and inhibit the shuttle effect. • The MoSSe/NC based Li-S battery exhibits excellent electrochemical performance. Lithium-sulfur (Li-S) batteries with high theoretical energy densities offer a promising alternative for next-generation energy storage. However, the poor conductivity, shuttle effect of lithium polysulfides (LiPSs), and large volume expansion upon cycling hinder their application. Hollow nanostructures can play an important role in achieving high sulfur loading, buffering volume expansion, and inhibiting LiPSs shuttling. In this work, MoSSe nanosheets grown on N-doped carbon hollow spheres (MoSSe/NC) are used as both sulfur host and separator to achieve catalytic adsorption and conversion of LiPSs. As a sulfur host, MoSSe/NC can enhance electron/ion transport and alleviate the volume expansion of sulfur during cycling, further accelerating the redox kinetics. The MoSSe/NC-modified separator can also induce interfacial charge modulation and expose more active sites, promoting rapid anchoring and conversion of LiPSs and uniform deposition of Li 2 S. Theoretical calculations and experiments verify that MoSSe/NC can catalyze the conversion of LiPSs, inhibit the shuttle effect, and effectively improve the electrochemical properties of sulfur. Therefore, the MoSSe/NC based Li-S battery exhibits high initial capacity (1455 mAh g−1), excellent rate performance (891 mAh g−1 at 2 C), and good cycling stability (0.049% capacity decay rate at 800 cycles at 1 C). MoSSe nanosheets grown on N-doped carbon hollow spheres (MoSSe/NC) are used as both sulfur host and separator to achieve catalytic adsorption and conversion of LiPSs. Theoretical calculations and experiments verify that MoSSe/NC can catalyze the conversion of LiPSs, inhibit the shuttle effect, and effectively improve the electrochemical properties of sulfur. [Display omitted] [ABSTRACT FROM AUTHOR]

The pursuit of efficient and durable bifunctional electrocatalysts for oxygen reduction reaction and oxygen evolution reaction is urgently needed for the development of highly reversible lithium-oxygen batteries. Perovskite oxides are emerging as a novel research frontier to simultaneously catalyze oxygen reduction and evolution reactions, however, their activity and durability are still far from desirable. Herein, we propose a rational design of Ni 3 S 2 decorated double perovskite PrBa 0.5 Sr 0.5 Co 2 O 5+δ as an integrated electrocatalyst. A Ni 3 S 2 layer with 10 nm thickness is uniformly anchored on electrospun PrBa 0.5 Sr 0.5 Co 2 O 5+δ nanofibers via the atomic layer deposition technology and the following sulfudation process. Notably, the lithium-oxygen batteries employing the as-prepared catalyst shows the excellent performance with a narrow overpotential (0.68 V at 1000 mAh g−1), a high capacity (12874 mAh g−1 at 100 mA g−1) as well as the improved cycle stability (over 120 cycles) and rate capacity. The outstanding performance arises from the synergistic coupling of Ni 3 S 2 and PrBa 0.5 Sr 0.5 Co 2 O 5+δ as well as the hierarchical porous structure with sufficient catalytic active sites. This work provides an innovative method to combine the metal chalcogenides and perovskite oxides, and the results suggest that the integrated Ni 3 S 2 /PrBa 0.5 Sr 0.5 Co 2 O 5+δ has a great potential as bifunctional electrocatalyst for the reversible lithium-oxygen batteries. Image 1 • Hierarchical Ni 3 S 2 /PBSC NFs with core-shell structure have been fabricated. • Ni 3 S 2 /PBSC NFs exhibited enhanced ORR/OER activities. • The synergy of Ni 3 S 2 and PBSC was responsible for the enhanced activities. • Ni 3 S 2 /PBSC based Li-O 2 batteries showed improved performance. [ABSTRACT FROM AUTHOR]

• TiO 2 /carbon nanofibers with in-situ Fe-doping was successfully prepared. • Fe-TiO 2 /carbon nanofibers could deliver a capacity of 140 mAh/g at 30 C. • Fe-TiO 2 /carbon nanofibers could achieve 98% capacity retention after 3000 cycles. TiO 2 is recognized as a promising anode material for sodium-ion batteries (SIBs) due to its low-cost and high structural stability, but it suffers from intrinsically poor electrical conductivity and low electrochemical activity at high rates. Herein, an in-situ Fe-doping strategy is designed to increase sodium-ion storage performance of TiO 2 /carbon nanofibers by a simple electrospinning method. The combination of Fe-doping with one-dimensional carbon structure could enable fast electron and Na+ ion transport of TiO 2. As a result, the Fe-TiO 2 /carbon nanofiber electrode exhibits high specific capacity (283 mAh g−1 at 0.5 C), excellent rate capability (140 mAh g−1 at 30 C) and long cycling stability (98% retention after 3000 cycles), which is obviously superior to pure TiO 2 /carbon nanofiber and other TiO 2 -based anodes reported in the literatures. These results indicates the powerful effect of in-situ Fe-doping for enhancing the Na-storage property of TiO 2. [ABSTRACT FROM AUTHOR]

Rare earth element-doped piezoelectric ceramics exhibit excellent electrical properties. Platinum group elements can render them catalytically active and conductive. In this study, lead-free Ba 0.95 Ca 0.05 Ti 0.94 Zr 0.06 O 3 piezoelectric ceramics doped with 0.12% lanthanum and iridium (varying contents, x) were sintered at 1260 °C. The thermal expansion coefficients and fracture strengths of these ceramics were affected by their strains and structural defects. With an increase in x , the diffuse phase transition weakened first and then accelerated (with further increase in x (> 0.75%)). The best ferroelectric properties were obtained at 400 ms and 25 kV/cm. The effects of the phase, structural defects, and internal stress on the electrical properties of the ceramics were systematically investigated. Relations of electrical properties, mechanical strength, and thermophysical performances were originally researched. In addition, the electrical properties (piezoelectric constants, ∼270 pC/N; mechanical quality factors, ∼ 70) and thermophysical performances (thermal expansion coefficient, ∼1.2 × 10−5 K−1) of the ceramics were found to be suitable for practical applications. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • g-C 3 N 4 /Mo 2 C hybrid photocatalyst with 1D heterostructure was successfully prepared. • The hybrid 1D/0D heterojunction of g-C 3 N 4 /Mo 2 C exhibited enhanced photocatalytic activity. • A possible photocatalytic mechanism based on the experimental results was proposed. Abstract Designing and optimizing visible-light-driven photocatalyst with cost-efficiency and high performance is very imperative and highly challenging for photocatalytic hydrogen evolution reaction. Herein, g-C 3 N 4 /Mo 2 C hybrid photocatalyst with one dimensional (1D) heterostructure for highly enhanced photocatalytic H 2 generation activity were obtained by a facile two step processing, in which Mo 2 C nanoparticles were highly dispersed on rod-like g-C 3 N 4 surface. Attributed to the synergistic effect of 1D structure and Mo 2 C co-catalyst, the resultant g-C 3 N 4 /Mo 2 C sample exhibits an impressive visible-light photocatalytic H 2 production rate of up to 507 μmol·h−1·g−1 and quantum efficiencies of 3.74% at 420 nm, which is 9.8 times higher than that of bulk g-C 3 N 4 , indicating that decorating Mo 2 C as co-catalysts on the surface of g-C 3 N 4 leads to the improved visible light absorption, promoted charge separation and enhanced the following H 2 -evolution rate. Moreover, the mechanism for the photocatalytic activity enhancement was also discussed. This study provides a guide for researchers to design efficient g-C 3 N 4 -based hybrid photocatalysts with excellent stability and photocatalytic activity during the photoreaction process. [ABSTRACT FROM AUTHOR]

Abstract Rational design of highly active, economical and stable electrocatalysts for hydrogen evolution reaction (HER) is still a great challenge for future applications. Herein, we use a 2D metal-organic framework array as the reactive template and precursor, to fabricate a hybrid nanosheet array of nitrogen-rich CoS 2 @nitrogen-doped carbon on Ti foil substrate (N–CoS 2 @NC/Ti) through a simple thermal treatment in the presence of thiourea. Owing to the prominent synergistic effect of the coupling between CoS 2 and NC, a high content of Co-N x species as well as unique nanoarray architectures, the as-synthesized N–CoS 2 @NC/Ti electrode exhibits remarkable activity and robust durability for HER under both acidic and alkaline conditions, which is obviously superior to the CoS 2 @NC/Ti. Graphical abstract Image 1 Highlights • A novel 2D Co-MOFs was used to fabricate N–CoS 2 @NC flake arrays. • The N–CoS 2 @NC/Ti has a high content of Co-Nx species. • Outstanding HER performance was achieved in acidic and alkaline medium. [ABSTRACT FROM AUTHOR]

Abstract Sodium-ion batteries have been widely considered as promising energy storage systems due to the abundance and low cost of sodium. However, to find a kind of anode material with appropriate sodium storage and high structural stability still remains challenging. In this work, self-supported porous carbon fibers were prepared by electrospinning technique and plasma treatments. It's found that the porous carbon fibers become more loose after the plasma treatments, and the surface compositions are changed. Results show that the material after plasma treatments could deliver capacities higher than 200 mAh/g when the current density is 1000 mA/g. EIS results show that the charge transfer resistances of the treated material keep more stable after electrochemical cycles. And these improvements may be results of the plasma treatments. Detailed mechanisms are studied in this research. Highlights • Loose and porous self-supported carbon materials are prepared. • Rate performances are improved after plasma treatments. • Charge transfer resistances of the material are more stable after plasma treatments. [ABSTRACT FROM AUTHOR]

A bimetallic sulfide MoS 2 -SnS heterostructure has been constructed by a salt-template method to modify the separator of Li-S batteries. The 3D porous MoS 2 -SnS heterostructure on N-doped carbon (MoS 2 -SnS/NC) can improve the LiPSs adsorption and accelerate the LiPSs conversion and Li 2 S uniform nucleation/deposition due to its pore structure, polar bond, and excellent catalytic properties. [Display omitted] • A MoS 2 -SnS heterostructure is used to modify the separator of Li-S batteries. • The LiPSs adsorption/conversion mechanism is deeply investigated. • MoS 2 -SnS/NC-PP exhibits excellent electrochemical performance. Lithium-sulfur (Li-S) batteries have been regarded as potential candidates for next-generation high-performance energy storage systems due to the rich sulfur reserves, nontoxicity, high theoretical capacity, and energy density. However, the Li-S batteries suffer from the slow reaction kinetics and lithium polysulfide (LiPSs) shuttling. To address these issues, a bimetallic sulfide MoS 2 -SnS heterostructure has been constructed by a salt-template method to modify the separator of Li-S batteries. The 3D porous MoS 2 -SnS heterostructure on N-doped carbon (MoS 2 -SnS/NC) can improve the LiPSs adsorption and accelerate the LiPSs conversion and Li 2 S uniform nucleation/deposition due to its pore structure, polar bond, and built-in electric field at the interface of MoS 2 and SnS. Therefore, the prepared MoS 2 -SnS/NC-PP heterostructure exhibits a high initial capacity (1504.6 mAh g-1), superior rate performance (690.1 mAh g-1 at 4C), and good cycling stability (0.07 % capacity decay rate at 400 cycles at 4C). When the sulfur loading is 3.50 mg cm−2, the Li-S battery delivers a capacity of 635 mAh g-1. [ABSTRACT FROM AUTHOR]

Developing highly active and low-cost electrocatalysts with superior durability is attractive but challenging for energy-saving electrolytic hydrogen generation via water electrolysis. Herein, a novel metal-organic framework (MOF)-based growth-etching-phosphorization strategy is reported to construct hierarchical porous CoP nanostructure arrays on nickel foam substrate (HP-CoP NA/NF) for overall water splitting (OWP). Interconnected 2D cobalt-based MOF are fabricated via an aqueous solution reaction at room temperature, and then solid MOFs are uniformly converted into porous CoP arrays with hierarchical 3D configuration through a Co 2+ −etching process with subsequent phosphorization treatment. This unique array architecture is beneficial for providing highly exposed active sites, shortening ion diffusion path and promoting gas release during the electrochemical reactions. Resultantly, this MOFs-derived CoP catalyst exhibits an outstanding electrocatalytic activity in catalyzing not only hydrogen and oxygen evolution reactions with the low overpotentials of 70 and 258 mV at 10 mA cm −2 , respectively, but also some other small molecules electro-oxidation reactions, especially for urea oxidation reaction. Furthermore, the two-electrode electrolyzer comprising bifunctional HP-CoP NA/NF electrode delivers a current density of 10 mA cm −2  at an ultralow cell voltage of 1.38 V in the presence of urea, which is 180 mV smaller than that of pure water splitting. This work introduces a reference for the development of MOF-derived hierarchical nanostructured catalysts for energy-saving water splitting. [ABSTRACT FROM AUTHOR]

(1 − x)Ba0.95Ca0.05Ti0.94Zr0.06O3-(x)Dy (x = 0-0.90 mol%) lead-free ceramics were prepared at 1190 °C with as-synthesized nanoparticles via a modified Pechini polymeric precursor method. X-ray powder diffraction, Raman spectrometer, and X-ray photoelectron spectroscopy were used to investigate the phase, symmetry, and valence state, respectively. The results indicated dysprosium could induce the phase transformation from O to R. The mechanism of defect complexes and oxygen vacancies that influenced by various dysprosium contents were discussed in detail. The results of dielectric, ferroelectric, and piezoelectric characteristics suggested the electrical properties were initially elevated with a trifling addition of dysprosium contents, and then decreased with further increased x. Moreover, reasons for diversified electrical properties, i.e., imbalanced long-range and short-range forces, changed octahedron structure, defect dipole, pinching effects of domain wall and element electronegative, were all stated in detail. The optimal physical properties, d33 = 371 pC/N, Qm = 87, and CTE2 = 1.23 × 10−5 K−1, were detected at x = 0.60 mol%, and those findings were regarded as prospect in the development of lead-free ferroelectric ceramic materials. [ABSTRACT FROM AUTHOR]

The desirable physi-chemical properties of perovskite oxides make them the promising cathode materials of rechargeable Li-O 2 batteries. Much attention is devoted to the structure design and the composite incorporation to develop the catalytic activity and durability of perovskite oxides used in the electrode. Herein, we propose an integration of atomic layered deposition iron oxide and perovskite LaNiO 3 as a novel catalyst for both oxygen evolution reaction (OER) and oxygen reduction reaction (ORR). Owing to the unique interconnected structure and the synergistic effect of Fe 2 O 3 and LaNiO 3 , the 6 nm thick Fe 2 O 3 /LaNiO 3 hybrid catalyst demonstrates the considerable intrinsic activities, which favorably outperforms other the state of the art perovskite catalysts. In addition, the Li-O 2 battery employing this tailored catalyst displays a significantly decreased reduced discharge/charge voltage gap of 0.77 V at 50 mA g −1 with good rate capability and considerable cycle stability, indicating the practical feasibility of Fe 2 O 3 /LaNiO 3 hybrid as a promising oxygen electrode catalyst for Li-O 2 batteries. This study highlights a new and feasible scheme to promote the bi-functionally of perovskite catalysts for the development of Li-O 2 batteries and other electrochemical devises. [ABSTRACT FROM AUTHOR]

The development of highly active dual-functional electrocatalysts, especially for oxygen evolution reaction (OER), is highly desirable to electrocatalyze water splitting for hydrogen production. Herein, a cobalt metal-organic frameworks (Co-MOFs) array is employed as the platform to fabricate oxygen-defect-rich Co 3 O 4 flakes that are vertical grown on nickel foam substrates. This MOFs-derived Co 3 O 4 arrays show a hierarchical interconnected porous flake network structure with tunable oxygen vacancies . The unique structural features obtained from an optimal hydrogenation condition render outstanding catalytic performance toward the oxygen evolution in alkaline media (an ultralow overpotential of 205 mV at 10 mA cm −2 ; a small Tafel slope of 65.3 mV dec −1 as well as high stability). This OER performance is among the best non-noble metal catalysts reported to date. Meanwhile, this defect-rich Co 3 O 4 array electrode is also efficient for catalyzing hydrogen evolution in the same basic solution (overpotential of ∼108 mV at 10 mA cm −2 ). The electrolyzer for overall water splitting can deliver a current density of 100 mA cm −2 at a cell voltage as low as 1.84 V. Density functional theory calculation reveals that the enhanced OER performance mainly arises from the oxygen vacancies and consequently the lowered activation energy as well as improved electrical conductivity. [ABSTRACT FROM AUTHOR]

Abstract: Developing low‐cost and efficient noble‐metal‐free photocatalytic materials is crucial for the hydrogen production through water splitting. Herein, N‐TiO2/g‐C3N4 heterostructure loaded with a noble‐metal‐free NixP cocatalyst was prepared by the combination of ammonia etching and photo‐reduction deposition method. The results demonstrated that N‐doped TiO2 (N‐TiO2) nanosheets were formed and stood upright on the surfaces of g‐C3N4 nanosheets, forming a 3D structure. The ternary hybridization of N‐TiO2/g‐C3N4@NixP hierarchical nanostructure was a promising strategy to achieve highly efficient photocatalytic H2 evolution, showing an optimized hydrogen evolution rate of 5438 μmol g−1⋅h−1 using 300 W Xe lamp as irradiation source, which was 7.5 times higher than that of N‐TiO2/g‐C3N4. The enhanced photocatalytic activity was ascribed to the combined effects of NixP cocatalyst loading and the formation of the intimate nanoheterojunctions between TiO2 nanosheets and g‐C3N4 nanosheets, which were favorable for promoting charge transfer. The present work would provide a novel facile preparation and practical application of many other noble‐metal‐free metal phosphides as a highly efficient cocatalyst for hydrogen production through water splitting. [ABSTRACT FROM AUTHOR]

Abstract: Achieving high‐performance Na‐ion capacitors (NICs) has the particular challenge of matching both capacity and kinetics between the anode and cathode. Here a high‐power NIC full device constructed from 2D metal–organic framework (MOFs) array is reported as the reactive template. The MOF array is converted to N‐doped mesoporous carbon nanosheets (mp‐CNSs), which are then uniformly encapsulated with VO2 and Na3V2(PO4)3 (NVP) nanoparticles as the electroactive materials. By this method, the high‐power performance of the battery materials is enabled to be enhanced significantly. It is discovered that such hybrid NVP@mp‐CNSs array can render ultrahigh rate capability (up to 200 C, equivalent to discharge within 18 s) and superior cycle performance, which outperforms all NVP‐based Na‐ion battery cathodes reported so far. A quasi‐solid‐state flexible NIC based on the NVP@mp‐CNSs cathode and the VO2@mp‐CNSs anode is further assembled. This hybrid NIC device delivers both high energy density and power density as well as a good cycle stability (78% retention after 2000 cycles at 1 A g−1). The results demonstrate the powerfulness of MOF arrays as the reactor for fabricating electrode materials. [ABSTRACT FROM AUTHOR]

Replacement of oxygen evolution (OER) by the more readily oxidized urea is considered to be a promising strategy for electrocatalytic water-splitting. In this work, we report a Fe O P film on nickel foam (Fe O P/NF) via atomic layer deposition (ALD) of iron oxide and a subsequent phosphonation process, which acts as a superior bifunctional electrocatalyst for both urea evolution reaction (UOR) and hydrogen evolution reaction (HER). Benefiting from the synergetic effects, the Fe O P/NF exhibits a low potential of 1.34 V (vs. RHE) at 10 mA cm −2 and a low Tafel slope of 57.2 mV dec −1 for UOR. Combined with the high HER activity of Fe O P/NF, the urea-based overall water splitting can be performed with an low voltage of 1.43 V to deliver 10 mA cm −2 in 1.0 M KOH with 0.5 M urea, which is 200 mV lower than that for pure water splitting. [ABSTRACT FROM AUTHOR]