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Zinc–air batteries are recognized for their environmental friendliness and high energy density; however, the slow kinetics of the oxygen reduction reaction (ORR) at the air electrode hinder their commercial viability. The research focuses on synthesizing cubic hollow carbon structures derived from Metal–Organic Frameworks (MOFs), which enhance catalytic performance through improved conductivity and mass transfer. The resulting Fe/Fe3C/HCNB catalyst demonstrates a half-wave potential of 0.826 V for ORR and achieves a peak power density of 274 mW cm−2 in zinc–air batteries, surpassing commercial Pt/C catalysts. Electrochemical impedance spectroscopy reveals that the hollow structure enhances hydrophilicity and reduces solution resistance, facilitating greater active site engagement in electrochemical reactions. The study concludes that the unique structural features of Fe/Fe3C/HCNB significantly improve discharge performance and stability, positioning it as a promising alternative for zinc–air battery applications. [ABSTRACT FROM AUTHOR]

Lowering the Schottky barrier at the metal–semiconductor interface remains a stern challenge in the field of field-effect transistors. Herein, an in-depth investigation was conducted to explore the formation mechanism of the Schottky barrier via interlayer distance and external electric field, utilizing the first-principles approach. Attributed to the vertical asymmetric structure of B2P6, ohmic contact forms at the interface of a graphene/B2P6(001) heterostructure, and an n-type Schottky contact with a Schottky barrier of 0.51 eV forms at the interface of a graphene/B2P6(001¯) heterostructure. Furthermore, the Schottky barrier height and the contact type can be changed by adjusting the interlayer spacing or applying an electric field along the Z direction. A high carrier concentration of 4.65 × 1013 cm−2 is obtained in the graphene/B2P6(001) heterostructure when an external electric field of 0.05 V Å−1 is applied. Verifiably, alterations in the energy band structure are attributed to the redistribution of charges at the interface. The new findings indicate that GR/B2P6 heterostructures are a key candidate for next-generation Schottky field-effect transistor development. [ABSTRACT FROM AUTHOR]

With the widespread application of big data, the amount of data transmitted through optical networks has been increasing dramatically. Correlated random bit generation (CRBG) is one of the key technologies in secure communication systems to ensure security performance and transmission efficiency. We propose and demonstrate a CRBG scheme based on a Mach–Zehnder modulator (MZM) electro-optic feedback loop to improve the security and speed of communication systems. In this scheme, common-signal-induced synchronization is accomplished to generate wideband complex physical entropy sources, and a private hardware module is employed to perform post-processing and nonlinear transformation of the synchronized signal. The simulation results show that the effective bandwidth of the output chaotic signal is significantly increased to 27.76 GHz, and high-quality synchronization with a correlation coefficient of over 0.98 is reached. A high-rate CRBG of up to 5.3 Gb/s is successfully achieved between two synchronized wideband physical entropy sources, and the hardware key space is enhanced to ∼2 42 , which greatly improves the privacy of physical entropy sources. The proposed scheme provides a promising approach for high-speed private CRBG, which is expected to be used in high-speed secure key distribution and optical communication systems. [ABSTRACT FROM AUTHOR]

Carbonaceous materials are regarded as prospective anode candidates of potassium‐ion batteries. However, the rate capability and cycling stability of classic carbon materials are still far from satisfactory. Herein, we exploit a facile and low‐cost strategy to enable the precise synthesis of sulfur/nitrogen co‐doped in‐plane porous carbon nanosheets with fishnet‐shaped microstructure (SN‐CNSs). The well‐designed in‐plane porous structure and the interconnected carbon flake network can accelerate the diffusion of potassium ions, alleviate volume expansion, and provide sufficient active sites. As a result, the SN‐CNSs deliver an impressively reversible capacity of 248 mAh g−1 at a current density of 1 A g−1 after 4500 cycles, and an excellent rate capacity of 137.3 mAh g−1 after 4000 cycles under 5 A g−1. Density functional theory (DFT) calculations further verify the advantage of S/N co‐doping in the adsorption/diffusion of K‐ion in SN‐CNSs materials. Such an excellent performance shows that SN‐CNSs possess a great potential to be a superior anode of potassium‐ion batteries. [ABSTRACT FROM AUTHOR]

Improving the sensitivity of MoS2-based photodetectors by constructing semiconductor heterostructures remains a challenge. To address this issue, the effects of interlayer spacing and vertical external electric fields on the interfacial interactions and electronic properties of Zr2CO2/MoS2 heterostructures were investigated systematically by first-principles calculations. The results indicate that a stable interface with van der Waals interactions can form between Zr2CO2 and MoS2, which complies with the type-II mechanism. By applying a vertical external electric field to the Zr2CO2/MoS2 heterostructure or changing the interlayer spacing between the Zr2CO2 and MoS2 monolayers, both the band gap and heterostructure type at the Zr2CO2/MoS2 interface can be modulated efficiently. It is remarkable that the band alignment of the Zr2CO2/MoS2 heterostructure is more sensitive to the external electric field than to the interlayer spacing. When the electric field is from −0.5 to 0.5 V Å−1, the energy band of the Zr2CO2/MoS2 heterostructure changes from 0.2 to 0.3 eV with a 0.1 V Å−1 increase of electric field. The redistribution of charge density with the external electric field and interlayer coupling is revealed to account for the tunable energy bands. Therefore, the Zr2CO2/MoS2 heterostructures with van der Waals interactions possess great potential to be used in high-performance photodetectors. [ABSTRACT FROM AUTHOR]

Antimony-based materials have been considered as highly competitive anodes for sodium-ion batteries (SIBs) because of their high theoretical capacity. However, the poor rate capability and fast capacity fading, originating from sluggish kinetics and volume expansion, greatly restrict their practical application. To address the above issues, an effective spraying method and one-step partial reduction process were utilized to synthesize Sb2O3@Sb nanoparticle impregnated in N-doped carbon microcages (Sb2O3@Sb@NC) offering extraordinary sodium storage capabilities and delivering an ultra-high rate performance of 175.1 mA h g−1 at 20 A g−1 and a superior capacity retention of 245.2 mA h g−1 after 10 000 cycles under 10 A g−1 for SIBs. Such unprecedented electrochemical properties of the Sb2O3@Sb@NC electrode can be ascribed to the comprehensive characteristics derived from multi-scale structural engineering: the fast electrochemical kinetics and tight packing of Sb2O3@Sb nanoparticles with carbon sheets, the strong Na+ adsorption ability of Sb2O3@Sb@NC enhanced by the synergistic effect of heterostructures and N-doping, the structural integrity strengthened by a robust interface bond of Sb–O–C, and the improved pseudocapacitive contribution. These distinct features enable the Sb2O3@Sb@NC anode to be a potential candidate for large-scale sodium ion storage. [ABSTRACT FROM AUTHOR]

An understanding of the high photocatalytic performance reported for MoS2/BiOI nanocomposite is far from satisfactory. Here, the interfacial interaction and electronic properties of a MoS2/BiOI heterostructure were investigated systematically for the first time by first-principle calculations incorporating a semi-empirical dispersion-correction scheme. Our results confirm the reasonable existence of van der Waals interactions and a favorable Z-scheme mechanism, based on the typical interfacial cohesive energy and the energy level lineup at the interface. Analyzing the charge density differences and work functions, the built-in electric field is formed along the direction from MoS2 to BiOI after the interface equilibrium, and facilitates the separation of photoinduced electron–hole pairs in the interface. Additionally, it can be inferred that the incorporation of MoS2 into BiOI increases the carrier mobility and improves light harvesting, in agreement with the previously reported experimental data. Our work provides an insight into the mechanism of the enhanced visible-light photocatalytic activity of a MoS2/BiOI heterostructure, and helps to design other new heterostructure combinations. [ABSTRACT FROM AUTHOR]

A strategy is proposed for modifying BiVO4 photoanode with CoNiO2 as a novel water oxidation cocatalyst to enhance PEC water splitting performance. The results show that CoNiO2 has the following functions: reducing photogenerated charge recombination centers; providing trapping sites to promote charge separation; improving the stability of the overall system; providing more active sites; and offering a lower overpotential. The BiVO4/CoNiO2 photoanode has a higher photocurrent density (1.16 mA cm−2 at 1.23 V vs. RHE), a lower onset potential (∼0.06 V vs. RHE), a larger IPCE (34.37%) and ABPE (0.163%), better stability and good rates of hydrogen evolution (0.0148 μmol cm−2 min−1) and oxygen evolution (0.0076 μmol cm−2 min−1). The strategy provides promising prospects for achieving efficient PEC water splitting performance using water oxidation cocatalysts. [ABSTRACT FROM AUTHOR]

A facile electrospinning technique followed by pre‐oxidation and carbonization treatment is adopted to synthesize silicon anode cladded with SiOx layer and N‐rich carbon nanofibers (Si@SiOx@NCNFs), in which post‐used polyacrylonitrile (PAN) yarn is chosen as single carbon source. As anode in Li‐ion batteries, elaborately designed Si@SiOx@NCNFs renders remarkable reversible capacities of 1045 mA h g−1 at the 500th cycle under a current density of 8 A g−1 at 80°C, and 828 mA h g−1 after subsequent 500 cycles at 15 A g−1, mainly ascribed to the distinct hierarchical structure, N‐rich nature and enhanced pesudocapacitive behavior. When Si@SiOx@NCNFs is matched with commercial cathode LiFePO4, full cell delivers a stable capacity of 140 mA h g−1 at 100 mA g−1, accompanying with an energy density of 455 Wh kg−1 at 50 °C. These conspicuous features undoubtedly enable Si@SiOx@NCNFs to be promising anode materials for high‐power lithium‐ion battery used in harsh conditions. [ABSTRACT FROM AUTHOR]

The surface properties of BiPO4 exert a significant effect on the photocatalytic performance under ultraviolet irradiation, but they have not been well explored, either experimentally or theoretically. Herein, for the first time, we systematically studied the structures and energetics of four low-index stoichiometric surfaces of monazite BiPO4 using density functional theory. A new scheme is proposed to correct the surface energy and compare this with the average surface energy. Both of the two schemes for the surface energies indicate that the order of the surface energies is (100) < (010) < (011) < (001), which is not completely consistent with their surface dangling bond densities. The main reason is incomplete PO4 tetrahedrons, namely, the existence of dangling P–O bonds in the bare (001) plane. However, only dangling Bi–O bonds are found in the other three low-index surfaces. It is obvious that the dangling bond density of the Bi atoms and the intact PO4 tetrahedrons are two crucial factors in the surface stability. Correspondingly, the differences in the planar-averaged electron density and the work function are presented to describe the charge distribution close to the surface. Furthermore, the equilibrium morphology calculated using the Wulff construction suggests that the (001), (010), (011) and (100) facets account for 15%, 33%, 16% and 36%, respectively. The two low-energy (100) and (010) facets dominate in the Wulff shape and make up almost 69% of the total crystal shape area. This work will provide theoretical guidance for the further design of effective BiPO4-based photocatalysts. [ABSTRACT FROM AUTHOR]

Controlling the p-type electrical transport behavior of nanoelectronic devices remains a grand challenge in reducing the Schottky barrier. To address this issue, we systematically investigate the effect of asymmetric Se doping on the interlayer interaction and electronic properties of a MoS2(1−x)Se2x/graphene heterostructure by first-principles calculations incorporating a semiempirical dispersion–correction scheme. The results show that the interfacial binding can be enhanced by Se doping inside the interface, while the effect of Se doping outside the interface is negligible on the interfacial binding. The type and height of the Schottky barrier can be tuned by changing the concentration and sites of the Se dopant at the interface. Further, it is found that by increasing the concentration of the Se dopant inside the interface the transition from an n-type Schottky barrier to a p-type can be realized, and a low p-type Schottky barrier is gained at the interface for highly efficient charge transfer. Lastly, it is confirmed that the redistribution of the interfacial charge leads to a shift of the Fermi level, and thus determines the type and height of the Schottky barrier. These conclusions provide rational evidence for the asymmetric doping concepts to design and fabricate MoS2-based field effect transistors. [ABSTRACT FROM AUTHOR]

The manipulation of the constituents of novel hetero-photocatalysts is an effective method for improving photocatalytic efficiency, but a theoretical understanding of the relationship between interlayer interaction and photocatalytic activity is still lacking. Herein, the interfacial interactions and electronic properties of MoS2/graphene oxide (GO) heterojunctions with various O concentrations were explored systematically by first-principles calculations. The results indicate that MoS2 and GO can form a stable van der Waals heterojunction, and enhance the built-in internal electric field from GO to the MoS2 surface with the increase in O concentration after interfacial equilibrium. It is inferred that the photogenerated electrons and holes naturally accumulate in the conduction band of GO and the valence band of MoS2, respectively, under the built-in internal electric field driving, indicating the formation of direct Z-scheme heterojunctions. In addition, a red shift of the light absorption edge and the shift up of the conduction band edge of MoS2/GO heterojunctions are observed with an increase in O concentration. It can be concluded that the O atom plays a crucial role in the energy band alignment of MoS2/GO heterojunctions for the improvement of photocatalytic performance. These results are beneficial to understand and design layered MoS2/GO photocatalytic systems or as cocatalysts with other semiconductors. [ABSTRACT FROM AUTHOR]

Aims This study aimed to investigate whether cabotegravir (CAB), an integrase inhibitor in development for treatment and prevention of human immunodeficiency virus-1, influences the pharmacokinetics (PK) of a levonorgestrel (LNG) and ethinyl oestradiol (EO)-containing oral contraceptive (OC) in healthy women. Methods In this open-label, fixed-sequence crossover study, healthy female subjects received LNG 0.15 mg/EO 0.03 mg tablet once daily Days 1-10 alone and with oral CAB 30 mg once daily Days 11-21. At the end of each treatment period, subjects underwent predose sampling for concentrations of follicle-stimulating hormone, luteinizing hormone, and progesterone and serial PK sampling for plasma LNG, EO, and CAB concentrations. Results Twenty women were enrolled, and 19 completed the study. One subject was withdrawn due to an adverse event unrelated to study medications. Geometric least squares mean ratios (90% confidence interval) of LNG + CAB vs. LNG alone for LNG area under the plasma concentration-time curve over the dosing interval of duration τ and maximum observed plasma concentration were 1.12 (1.07-1.18) and 1.05 (0.96-1.15), respectively. Geometric least squares mean ratio (90% confidence interval) of EO + CAB vs. EO alone for EO area under the plasma concentration-time curve over the dosing interval of duration τ and maximum observed plasma concentration were 1.02 (0.97-1.08) and 0.92 (0.83-1.03), respectively. Steady-state CAB PK parameters were comparable to historical values. There was no apparent difference in mean luteinizing hormone, follicle-stimulating hormone, and progesterone concentrations between periods. No clinically significant trends in laboratory values, vital signs, or electrocardiography values were observed. Conclusions Repeat doses of oral CAB had no significant effect on LNG/EO PK or pharmacodynamics, which supports CAB coadministration with LNG/EO OCs in clinical practice. [ABSTRACT FROM AUTHOR]

CoFeO (CFO)/BaTiO (BTO) magnetoelectric (ME) ceramic composites were prepared by spark plasma sintering (SPS) with mechanically mixed powders. The unwanted phases, atomic interdiffusion and microcracks emerged in the conventional sintering process were prevented in the SPS process. The CFO/BTO ceramics showed great densities measured by the Archimedes method. In this paper, the ferromagnetic, ferroelectric, and ME properties of the ceramic composites were well studied. The strongly optimized ME voltage coefficient up to as high as 180 mV/cm Oe was obtained in the spark plasma sintered CFO/BTO ceramics. The theoretical ME voltage coefficients of the ceramics were also calculated by the finite-element method. The reasons for the improvement of the ME voltage coefficient and the lower experimental ME value comparing to the calculations were both discussed in this paper. [ABSTRACT FROM AUTHOR]

Cover Feature: Sulfur/Nitrogen Co-Doped In-Plane Porous Carbon Nanosheets as Superior Anode of Potassium-Ion Batteries (Batteries & Supercaps 5/2022) Carbon nanosheets, DFT calculations, low temperature graphitization, porous structure, potassium-ion batteries anode Keywords: carbon nanosheets; DFT calculations; low temperature graphitization; porous structure; potassium-ion batteries anode EN carbon nanosheets DFT calculations low temperature graphitization porous structure potassium-ion batteries anode 1 1 1 05/10/22 20220501 NES 220501 B The Cover Feature b shows porous carbon nanosheets with fishnet-like microstructures, featuring excellent potassium-ion storage capacity as anodes for potassium-ion batteries, possessing great potential for powering the future city. [Extracted from the article]

The effect of functional groups (O, F, or OH) on the hydrogen storage properties of Ti 2 X (X = C or N) monolayer was systematically investigated by first-principles calculations. The results show that the reversible hydrogen storage capacity of Ti 2 X(OH) 2 monolayer is approximately 2.7 wt%, which is larger than that of Ti 2 XO 2 and Ti 2 XF 2 monolayers. The binding energy of the OH group at the F site is stronger than H atom. Thus, H 2 molecules will not be dissociated on Ti 2 X(OH) 2 monolayer. At this time, the loss of 1.8 wt% hydrogen storage capacity is not produced in Ti 2 X(OH) 2 monolayer. Furthermore, the PDOS, the population analysis, and the electron density difference explore that electron transfer appears between Ti and the second layer H 2 molecules on Ti 2 X(OH) 2 monolayer, and a Dewar-Kubas interaction lies between second layer H 2 molecules and Ti 2 X(OH) 2 monolayer. For Ti 2 X(OH) 2 monolayer, the molecular dynamic simulation indicates that the H 2 molecules by Dewar-Kubas interaction sable adsorption at 300 K, and desorption at 400 K. Therefore, Ti 2 X(OH) 2 is appropriate for reversible hydrogen sorbent storage materials under ambient conditions. [Display omitted] • Strong chemical interaction exists between hydrogen atom and bare Ti 2 X. • Reversible hydrogen storage method using functional groups to regulate Ti 2 X. • All hydrogen molecules adsorb on Ti 2 XO 2 and Ti 2 XF 2 are irreversible. • Some hydrogen molecules by Kubas interaction adsorb on Ti 2 X(OH) 2 are reversible. • Total hydrogen storage capacity of Ti 2 X(OH) 2 is 5.3 wt%; Reversible part is 2.7 wt%. [ABSTRACT FROM AUTHOR]

A strategy is proposed for modifying BiVO4 photoanode with CoNiO2 as a novel water oxidation cocatalyst to enhance PEC water splitting performance. The results show that CoNiO2 has the following functions: reducing photogenerated charge recombination centers; providing trapping sites to promote charge separation; improving the stability of the overall system; providing more active sites; and offering a lower overpotential. The BiVO4/CoNiO2 photoanode has a higher photocurrent density (1.16 mA cm−2 at 1.23 V vs. RHE), a lower onset potential (∼0.06 V vs. RHE), a larger IPCE (34.37%) and ABPE (0.163%), better stability and good rates of hydrogen evolution (0.0148 μmol cm−2 min−1) and oxygen evolution (0.0076 μmol cm−2 min−1). The strategy provides promising prospects for achieving efficient PEC water splitting performance using water oxidation cocatalysts. [ABSTRACT FROM AUTHOR]

Nitrogen reduction reactions (NRRs) under mild conditions retain an enormous challenge in effective N 2 activation on metal-based catalysts. Here, by spin-polarized DFT calculations, we systematically investigated the potential of single transition-metal atoms (Sc to Zn, Nb to Cd, W, Pt and Au) supported on the experimentally available WS 2 nanosheets with sulfur vacancies as catalysts for N 2 fixation and conversion. The results confirm that the WS 2 nanosheet with sulfur vacancies is a good platform for anchoring single transition-metal atoms. Based on proposed several criteria, it is found that the single Ni atoms anchored to sulfur vacancies possess outstanding catalytic activity of NRR. Here, the Ni-WS 2 nanosheet acts as likely Lewis-acid system and accepts electrons from the N 2 *, which causes the weakening of N–N bond. Reaction energy diagrams of the NRRs show that the whole NRRs on Ni-WS 2 surface prefer to occur along the alternating associative pathway, and form the ammonia without the requirement of energy input. Overall, our results reveal that the Ni-WS 2 system is a quite promising single-atom catalyst with less energy-consuming and good stability for NRRs. These findings could motivate more experimental and theoretical researches to further explore the potential of single transition-metal atoms anchored to two-dimensional substrate materials for NRRs. Unlabelled Image • WS 2 nanosheet with S-vacancies is potential substrate for anchoring single TM atoms. • Single Ni atom anchored to the S-vacancy possesses outstanding NRR catalytic activity. • Stability of reaction intermediate relates to the charge difference between two nitrogen atoms. • NRR on Ni-WS 2 surface prefers to occur along the alternating associative pathway. • Ammonia can form on the Ni atom without the requirement of energy input. [ABSTRACT FROM AUTHOR]