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An ideal photocatalyst should have high redox capacity, efficient charge separation, and large reaction surface area. However, it is an extreme challenge to construct a photocatalytic system with above three merits. Herein, the g-C 3 N 4 /Bi@Bi 2 WO 6 composite photocatalyst was prepared by simple wet chemical method. Then the separation pathway of photoinduced charges through the interface was explored by XPS, EPR and active species capture experiments, confirming that the Z-scheme charge transfer route was followed. The optimized composite photocatalyst exhibited the photocatalytic hydrogen production rate of 1219.3 μmol h−1g−1, which is 2.29 times that of pure g-C 3 N 4 (533.4 μmol h−1g−1). Moreover, the photocatalytic degradation rates of RhB and TC were 82.43% and 66.7%, respectively, which were 7.55 times and 1.92 times that of pure Bi 2 WO 6. Ultimately, the enhanced photocatalytic performances were attributed to the synergistic effect of 2D/2D coupling interface and the deposited metal Bi, which not only benefited the efficient charge separation and fast charge migration but also provided the large reaction surface area. In addition, surface plasmon resonance effect of metal Bi can boost the visible light absorption and broaden the light absorption range to the full spectrum. Our study provides a new idea to design high-performance Z-scheme photocatalyst for highly efficient utilization of solar energy. • The idea of construction Z-scheme heterojunction system have high redox capacity, efficient charge separation, and large reaction surface area. • The enhanced photocatalytic performances were attributed to the synergistic effect of 2D/2D coupling interface and the deposited metal Bi. • The SPR effect of metal Bi can promote visible light absorption and broaden the light absorption range. [ABSTRACT FROM AUTHOR]

Ag quantum dots/g-C 3 N 4 (Ag QDs/g-C 3 N 4 ) photocatalysts were directly obtained via a novel one-step method. The photocatalysts were composed of Ag quantum dots with an average diameter of ca.5 nm, which were dispersed uniformly on the surface of g-C 3 N 4 nanosheets. By using methanol as sacrificial reagent, the Ag QDs/g-C 3 N 4 photocatalysts exhibited higher photoactivity for hydrogen production than the AX = 0 photocatalyst under visible-light irradiation (λ > 420 nm). Among various photocatalysts prepared, the AX = 0.5% photocatalyst showed maximum hydrogen production efficiency, which was enhanced by 4.6 times compared to AX = 0 photocatalyst. Our findings demonstrated that the coupled Ag QDs could enhance the visible light absorption and serve as g-C 3 N 4 electron acceptor for effective charge separation, and further increased it’s photocatalytic activity. [ABSTRACT FROM AUTHOR]

Perovskite oxides with a low overpotential and fine stability for oxygen evolution reaction (OER) are critical for achieving efficient energy conversion and storage. Herein, we reported a simple one-step approach to synthesize SrCo 0.5 Fe 0.3 Mo 0.2 O 3-δ /Co 3 O 4 heterostructure catalyst by adjusting the stoichiometric ratio of Co in the perovskite of SrCo x Fe 0.3 Mo 0.2 O 3-δ. Multiple active sites, abundant oxygen vacancies and rapid charge transfer induced by dispersed and tight interfaces generate unique synergy. SrCo 1.7 Fe 0.3 Mo 0.2 O 3-δ oxide with optimized composite structure only needs 277 mV to reach a current density of 10 mA cm−2 and shows a negligible overpotential rise after chronopotentiometry test in 1.0 M KOH. The cost-effective hybrid approach reported in this work could be extended to other hybrid systems, and this excellent electrocatalyst could also be a promising candidate for overall water splitting. [Display omitted] ● A facile hybrid strategy to achieve SrCo 0.5 Fe 0.3 Mo 0.2 O 3-δ /Co 3 O 4 heterostructure. ● Strong interactions are formed between perovskite and Co 3 O 4. ● The introduction of Co 3 O 4 causes increased densities of Co3+ and oxygen vacancies. ● The optimal catalyst exhibits a low overpotential of 277 mV @ 10 mA cm−2. [ABSTRACT FROM AUTHOR]

Photocatalysis is an effective way to treat industrial wastewater. Therefore, the design of low-cost and high-activity photocatalysts is crucial for environmental remediation. Herein, a ternary Z-Scheme LaFeO 3 /MoS 2 /graphene nanocomposite photocatalyst was synthesized by a facile two-step hydrothermal approach and tested for the degradation of dye wastewater. To this end, graphene was employed as a substrate for loading LaFeO 3 nanospheres and MoS 2 nanosheets to act as an electron migration medium for Z-scheme heterojunction. The obtained LaFeO 3 /MoS 2 /graphene photocatalyst showed high efficiency and stable performance toward the degradation of methylene blue (MB), estimated to 16.5-fold higher than that of sole LaFeO 3. The enhanced photocatalytic activity was mainly attributed to the synergistic effect between LaFeO 3 and MoS 2 /graphene co-catalyst, leading to the expansion of the visible light absorption range and optimization of the redox potential. Most importantly, the closely contacted Z-scheme heterojunction interface between LaFeO 3 and MoS 2 /graphene facilitated the separation and transport efficiency of photogenerated carriers, as well as prolonged the lifetime of photogenerated carriers. In sum, these results look promising for the future design of highly efficient LaFeO 3 -based photocatalysts with Z-scheme heterojunction structures. [Display omitted] • MoS 2 /graphene co-catalyst decorated LaFeO 3 was synthesized by hydrothermal method. • The degradation efficiency of LFO-50 M-10 G is 16.5-fold higher than that of pure LaFeO 3. • Appropriate MoS 2 /graphene modification LaFeO 3 had constructed Z-scheme heterojunction. • Both the charge separation and the visible-light absorption had enhanced in nanocomposites. • The hydroxyl radicals played a critical role in degradation of MB. [ABSTRACT FROM AUTHOR]

High-entropy alloys (HEAs) with a face-centered cubic structure offer numerous advantages, including high plasticity, good processability, and high-temperature resistance. They are also suitable for use as materials in shaped-charge liners, which can cause significant damage. In this study, CoCrFeNi HEAs were prepared, and their mechanical characteristics were examined. The results indicated that the alloy exhibited good plasticity and processability. After dynamic compression, the samples were analyzed using electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM). It was found that dislocation was the primary deformation mechanism at low strain rates. However, as the strain rate increased, the deformation mechanism shifted from dislocations to a combination of dislocations and twinning. The damage performance of the CoCrFeNi HEA was verified through a static penetration experiment using a conical charge. The results were then compared with simulation results obtained using the AUTODYN software. This study demonstrated that the CoCrFeNi HEA could form a condensed, stable-shaped charge jet, leading to efficient damage after penetrating the steel target plate. Therefore, after uniform treatment, the CoCrFeNi HEA can be utilized as a high-energy structural material to design shaped charge structures that achieve highly efficient damage. • CoCrFeNi HEA has excellent comprehensive mechanical properties. • CoCrFeNi HEA liner can form a continuous jet. • CoCrFeNi HEA jet has excellent penetration ability. • CoCrFeNi HEA exhibits the property of releasing impact energy. [ABSTRACT FROM AUTHOR]

Abstract Development of high-performance supercapacitors with high energy density is urgently required for energy storage device but remains challenging. In this work, novel NiCo 2 O 4 @Ni(OH) 2 (denoted as NCO-NH) core-shell nanoarrays were synthesized. Benefiting from the structural and compositional advantages, the NCO-NH core-shell nanoarrays exhibited high specific capacitances (2218.0 and 1796.0 F g−1 at current densities of 1 and 10 A g−1, respectively) and outstanding cycling stability (96.4% retention of the initial specific capacitance at 10 A g−1 after 5000 cycles). Using such NCO-NH nanoarrays as cathode and activated carbon as anode, an asymmetric supercapacitor (ASC) is further fabricated. This ASC device achieves a high energy density of 98.5 W h kg−1 at a power density of 800 W kg−1 (at current densities of 1 A g−1) and an energy density of 61.5 W h kg−1 at a high power density of 8000 W kg−1 (at current densities of 10 A g−1). This work highlights that construction of core-shell nanoarrays by coupling of bimetallic oxide with hydroxide could be a feasible way to obtain advanced electrode materials for high-performance supercapacitors. Graphical abstract Image 1 Highlights • NiCo 2 O 4 @Ni(OH) 2 core-shell nanoarrays have been successfully fabricated. • The core-shell nanoarrays electrodes showed high specific capacitance. • The core-shell nanoarrays electrodes exhibited outstanding cycling stability. • The ASC device based on core-shell nanoarrays can deliver high energy density. [ABSTRACT FROM AUTHOR]