Table of contents

We proposed a dislocation sink technology for achieving Si_1−xGe_x multi-bridge-channel field-effect-transistor beyond 5 nm transistor design-rule that essentially needs an almost crystalline-defect-free Si_1−xGe_x channel. A generation of a dislocation sink via H⁺ implantations in a strain-relaxed Si_0.7Ge_0.3 layer grown on a Si substrate and a following annealing almost annihilate completely misfit and threading dislocations located near the interface between a relaxed Si_0.7Ge_0.3 layer and a Si substrate. A real-time (continuous heating from room temperature to 600 °C) in situ high-resolution-transmission-electron-microscopy and inverse-fast-Fourier-transform image observation at 1.25 MV acceleration voltage obviously demonstrated the annihilation process between dislocation sinks and remaining misfit and threading dislocations during a thermal annealing, called the [Si_I or Ge_I + V_Si or V_Ge → Si_1−xGe_x] annihilation process, where Si_I, Ge_I, V_Si, and V_Ge are interstitial Si, interstitial Ge, Si vacancy, and Ge vacancy, respectively. In particular, the annihilation process efficiency greatly depended on the dose of H⁺ implantation and annealing temperature; i.e. a maximum annihilation process efficiency achieved at 5 × 10¹⁵ atoms cm⁻² and 800 °C.

As one type of advanced alternative batteries, zinc-ion batteries (ZIBs) have attracted increasing attention because of their advantages of cost-effectiveness, high safety and environmentally benign features. However, the performance of cathode materials has become a bottleneck for the future application of ZIBs. In recent years, manganese dioxide (MnO₂)-based materials as cathodes for ZIBs have been intensively explored. In this review, recent advances in MnO₂-based cathode materials for ZIBs are comprehensively reviewed with a discussion about the reaction mechanisms for the fundamental understanding of the electrochemical processes. Furthermore, several challenges hindering the technology maturity are also analyzed with corresponding strategies to further improve the electrochemical performance of such Zn–MnO₂ batteries.

Geobacter sulfurreducens is an important model organism for understanding extracellular electron transfer (EET), i.e. transfer of electrons from the cell's interior (quinone pool) to an extracellular substrate. This exoelectrogenic functionality can be exploited in bioelectrochemical applications. Nonetheless, key questions remain regarding the mechanisms of this functionality. G. sulfurreducens has been hypothesized to employ both multi-heme cytochromes and soluble, small molecule redox shuttles, as the final, redox-active species in EET. However, interactions between flavin redox shuttles and outer membrane, redox proteins in Geobacter have not been demonstrated. Herein, the heterologous expression and purification from E. coli of a soluble form of the multi-heme cytochrome OmcZs from G. sulfurreducens is reported. UV–vis absorption assays show that riboflavin can be reduced by OmcZs with concomitant oxidation of the protein. Fluorescence assays show that oxidized OmcZs and riboflavin interact with a binding constant of 34 μM. Furthermore, expression of OmcZs in E. coli enables EET in the host, and the current produced by these E. coli in a bioelectrochemical cell increases when riboflavin is introduced. These results support the hypothesis that OmcZs functions in EET by transiently binding riboflavin, which shuttles electrons from the outer membrane to the extracellular substrate.

We propose a scheme of quantum plasmon sensing system based on strong photon–exciton coupling in the gap surface plasmon nanostructure. The system's sensitivity is characterized as Rabi splitting, which is sensitive to a slight change in environmental permittivity and determined by the coupling coefficient and detuning between the emitter and plasmon nanocavity. By increasing the dipole moment of the emitter, the sensitivity can exceed that of a traditional plasmon sensing system while only depending on the resonance spectral shift. Quantum plasmon sensing provides a unique mechanism in the application of bio-sensing, opto-chemical sensing, and quantum photonics at the nanoscale.

The abuse of antibiotics has led to the emergence of numerous super resistant bacteria, which pose a serious threat to public health. Developing nanomaterials with novel modes of bactericidal activity offers the promise of fighting pathogens without the risk of causing drug resistances. Here, we used reduced graphene oxide (rGO), bulk molybdenum disulfide (MoS₂) and silver nitrate (AgNO₃) to synthesize a ternary nanocomposite, rGO–MoS₂–Ag, via a simple one-pot method. The resulting rGO–MoS₂–Ag presented as crumpled and sheet-like structures decorated with Ag nanoparticles. The minimum inhibitory concentration and minimum bactericidal concentration of rGO–MoS₂–Ag against Escherichia coli were 50 and 100 μg ml⁻¹, while Staphylococcus aureus reacted only to twice higher concentrations of 100 and 200 μg ml⁻¹, respectively. Notably, rGO–MoS₂–Ag exhibited better antibacterial activity towards E. coli and S. aureus than rGO, MoS₂, or rGO–MoS₂. This result can be attributed to the excellent performance of rGO–MoS₂–Ag in destroying the bacterial cell membrane and inducing the generation of reactive oxygen species. The Ag⁺ ion release of rGO–MoS₂–Ag was delayed, endowing the nanocomposite with long-term antibacterial capabilities and better biosafety. Our results indicate that the as-prepared rGO–MoS₂–Ag has promising potential for application in biomedicine and public health.

Nonassociative learning is a biologically essential and evolutionarily adaptive behavior in organisms. The bionic simulation of nonassociative learning based on electronic devices is essential to the neuromorphic computing. In this work, nonassociative learning is mimicked by a ZnO nanowire memristor without any other peripheral control circuit. The memristor demonstrates habituation and sensitization behaviors at the electrical and optical stimuli. Typical network-level parametric characteristics of habituation in neuroscience are realized in the memristor. When the heterogeneous stimuli are applied coincidentally, sensitization pulse could be identified by the exceptional response current. The results show that the natural selection rules could be simulated by the current single memristor. A possible mechanism based on the trapping states and adsorption of oxygen at the interface of Au/ZnO is proposed. The implementation of nonassociative learning in a single memristor device paves the way for building neuromorphic systems by simple electronic devices.

We demonstrate that a planar single-walled carbon nanotube (SWCNT) film bolometer can exhibit enhanced thermal and optical properties. The SWCNT film were ink-printed on an oxidized silicon substrate between two pointed-tip Au electrodes across a gap of approximately 10 μm. We obtained a bolometer figure-of-merit temperature coefficient of resistance of greater than –3.0% at room temperature. An optical response of 1000 V W⁻¹ was obtained from a 786 nm laser with an output power of 5 mW. The corresponding thermal time constant of 1.8 ms was estimated through the optical response by modulating the laser over a frequency range of 1 Hz–1 kHz. The optical noise equivalent power and optical detectivity of $4.5\times {10}^{-11}\,{\rm{W}}/\sqrt{{\rm{Hz}}}$ and $4.9\times {10}^{8}\,{\rm{cm}}\,\sqrt{{\rm{Hz}}}\,{{\rm{W}}}^{-1},$ respectively, were estimated from the responsivity, the spectral density, and area of the cell of the absorber, 4.9 × 10⁻⁴ cm². We attribute the exceptional performance of the SWCNT microbolometer to the film nature of the absorber and to the high concentration of the incident electromagnetic radiation and localized heating between the tips of the electrode.

The origin of dielectric breakdown was studied on 4H-SiC MOSFETs that failed after three months of high temperature reverse bias stress. A local inspection of the failed devices demonstrated the presence of a threading dislocation (TD) at the breakdown location. The nanoscale origin of the dielectric breakdown was highlighted with advanced high-spatial-resolution scanning probe microscopy (SPM) techniques. In particular, SPM revealed the conductive nature of the TD and a local increase of the minority carrier concentration close to the defect. Numerical simulations estimated a hole concentration 13 orders of magnitude larger than in the ideal 4H-SiC crystal. The hole injection in specific regions of the device explained the failure of the gate oxide under stress. In this way, the key role of the TD in the dielectric breakdown of 4H-SiC MOSFET was unambiguously demonstrated.

Recently, coloring based on nanostructure-light interaction has attracted much attention, because it has many advantages over pigment-based conventional coloring in terms of being non-toxic and highly durable in the environment, and providing high resolution. The asymmetric Fabry–Perot (FP) cavity absorber is the most manufacturable structure among coloring structures because it is simply produced and easily tunable. However, it cannot be applied practically because of the lack of a manufacturing technique that enables simultaneous fabrication of multi-color structures with different heights. Here, the fabrication of colored reflective characters based on various asymmetric FP absorbers with micrometer-scale pixel size are reported. Various cavities with different thicknesses are fabricated in a single step using UV imprint lithography and a simple deposition process. UV/visible spectroscopy is used to characterize the fabricated FP resonator. This absorber demonstrates high absorption, close to 90%, resulting in vivid colors with high resolution of 12700 DPI. It can be potentially used in reflective color displays field, functionalized color decorations, and security color patterns area. It is believed that this study would open up new possibilities for high density color printing in practical industry by introducing cost effective nanoimprint lithography technology.

Development of wearable devices for continuous respiration monitoring is of great importance for evaluating human health. Here, we propose a new strategy to achieve rapid respiration response by confining conductive polymers into 1D nanowires which facilitates the water molecules absorption/desorption and maximizes the sensor response to moisture. The nanowires arrays were fabricated through a low-cost nanoscale printing approach on flexible substrate. The nanoscale humidity sensor shows a high sensitivity (5.46%) and ultrafast response (0.63 s) when changing humidity between 0% and 13% and can tolerate 1000 repetitions of bending to a curvature radius of 10 mm without influencing its performance. Benefited by its fast response and low power assumption, the humidity sensor was demonstrated to monitor human respiration in real time. Different respiration patterns including normal, fast and deep respiration can be distinguished accurately.

We report a facile technique to fabricate manganese dioxide (MnO₂) encapsulated titanium dioxide (TiO₂) nanofiber heterostructure for its use as an electrode material in aqueous electrolyte based asymmetric supercapacitor (SC). MnO₂ coated TiO₂ nanofibers, prepared by electrospinning and post-hydrothermal process exhibited superior electrochemical properties in aqueous Na₂SO₄ electrolyte. The MnO₂ shell with average thickness of approximately 10 nm contributed to the high electrochemical performance for charge storage by redox reaction and intercalation mechanisms, while the anatase phase TiO₂ core provided an easy pathway for electronic transport with additional electrochemical stability over thousands of charge–discharge cycles. An asymmetric SC designed from the MnO₂–TiO₂ nanofiber electrode and single walled carbon nanotubes electrode showed high operating voltage window (2.2 V) with maximum gravimetric capacitance of 111.5 F g⁻¹.

In this work, a cerium doped CoP nanoparticles (NPs) embedded in carbon nanotubes (CNTs) for efficient and durable hydrogen evolution was developed. The detailed preparation process was described as the followings. First, cerium was introduced into ZIF-67 to form Ce-doped ZIF-67 by a joint nucleation method. Then, the Ce-doped Co-CNTs was synthesized by carbonization of Ce-doped ZIF-67. During the process, the Co²⁺ was reduced to form Co NPs and the elegant nanostructure of CNTs was formed by the catalytic effect of Co NPs. Finally, by using Ce-doped Co-CNTs as the precursor, the target catalyst (Ce_0.05-doped CoP CNTs) was obtained through a chemical vapour deposition (CVD) process in the presence of NaH₂PO₂. Results of the transmission electron microscopy (TEM) and scanning electron microscopy (SEM) showed that the target catalyst maintained the original rhombic dodecahedron morphology of ZIF-67 and the CoP NPs were embedded in CNTs and distributed uniformly throughout the catalyst. In electrochemical measurements, the catalyst showed the best performance for HER in 0.5 M H₂SO₄ solution. The onset potential, Tafel slope, electron transfer resistance (R_ct) and double-layer capacitance (C_dl) of the target catalyst was 49 mV, 78 mV dec⁻¹, 19.2 Ω and 10.5 mF cm⁻², respectively. Meanwhile, the catalyst yielded a current density of 10 mA cm⁻² merely at an overpotential of 146 mV. Furthermore, it maintained 90% of the original current density in a chronoamperometry measurement and showed no obvious decay even after 2000 cycles scans in a long-term durability test.

3D porous nanosheet arrays are desirable structures for supercapacitors due to their large surface and fast transportation for ions and electrons. However, their synthesis usually involves two or more steps, which is not only time-consuming but also makes the in situ growth more difficult to achieve. In this work, 3D porous NiCoSe₂ nanosheet array were in situ synthesized on Ni foam by one-step electrodeposition, and then employed as a supercapacitor electrode for the first time. The electrodeposited NiCoSe₂ electrode displays a high specific capacity of 520 C g⁻¹ at 1 A g⁻¹ and good rate capability of 53.7% with a 30-fold increase to 30 A g⁻¹. In addition, an asymmetric supercapacitor (ASC) device was assembled with NiCoSe₂ and activated carbon as the binder-free positive and negative electrode, respectively. The ASC exhibits a high specific energy of 44.4 Wh kg⁻¹ at a specific power of 776.7 W kg⁻¹, and outstanding cycling stability of 133% after 10000 cycles. Most importantly, the energy storage mechanism of NiCoSe₂ was proposed. This is mainly due to the significantly increased electroactive surface area and superior electron transfer properties of NiCoSe₂, which can compensate for the capacity decay of NiCoSe₂ induced by Se and Co loss after cycling.

Herein, we design a dual-template-assisted pyrolysis method to prepare ultra-small Fe₃O₄ nanoparticles anchored on Fe/N-doped hollow porous carbon spheres (0.010-Fe/NHPCS-800) for oxygen reduction reaction (ORR). The synthesized SiO₂ nanospheres, which are selected as the hard template, contribute to forming macroporous structure. Pluronic ® F127 is employed to fabricate mesopores through high-temperature pyrolysis as a soft template. In this way, the 0.010-Fe/NHPCS-800 architecture represents an ordered hierarchically porous property with a large BET surface area (1812 m² g⁻¹), which can facilitate the mass transport of reactants and increase the electrochemically active area. The Fe₃O₄ nanoparticles wrapped by graphitic carbon layers provide more active sites, and the synergistic interaction between Fe₃O₄ nanoparticles and doping N has a positive effect on ORR performance. The 0.010-Fe/NHPCS-800 catalyst outperforms the most effective ORR activities among a series of Fe/NHPCS samples with onset potential of 0.95 V (versus reversible hydrogen potential) and half-wave potential of 0.81 V, which is almost the same as the commercial Pt/C (0.96 and 0.81 V, correspondingly) in 0.10 M KOH. However, both the stability and durability of 0.010-Fe/NHPCS-800 surpass those of commercial Pt/C. Given all these advantages, 0.010-Fe/NHPCS-800 is a promising candidate to take the place of Pt-based electrocatalysts for ORR in the future.

By exploiting the storage performance of supercapacitors, iron has the potential to be used as a new anode material. However, this potential is limited by unsatisfactory electrical conductivity and poor cycling stability which impact the energy and power density. Consequently a foundation for improving the electrical conductivity and cycling stability of iron materials to obtain good storage performance is needed. In this work, Ag-modified Fe₂O₃ nanoparticles on carbon cloth were synthesized as an anode material for supercapacitors. The specific capacitance of the composite material reaches 10.39 F cm⁻² (2734.2 F g⁻¹) at a current density of 1 mA cm⁻² and remains at 83% of this value after 12 000 cycles. The energy density is 379.8 Wh kg⁻¹ at a power density of 131.6 W kg⁻¹ and remains at 123.9 Wh kg⁻¹ at a power density of 2631.6 W kg⁻¹. The electrical conductivity and interfacial effect created between Ag@Fe₂O₃ is confirmed with density functional theory calculations. The packaged asymmetric supercapacitor devices have flexibility and can light ten LEDs for 2 min 30 s, with an energy density of 60.3 Wh kg⁻¹ that can be reached at a power density of 1063.8 W kg⁻¹ and remain at 16 Wh kg⁻¹ even at a power density of 4255.3 W kg⁻¹.

In this work, silver nanoparticles (Ag NPs) were decorated into the cavities of ZIF-8 to fabricate a novel Ag NPs/ZIF-8 modified glassy carbon electrode (GCE) for electrochemical sensing of chloride ion. Benefiting from the synergistic properties of ZIF-8 and Ag NPs, the Ag NPs/ZIF-8/GCE showed favorable performance towards chloride ion. For comparison, the electrochemical activity of Ag NPs wrapped by ZIF-8 (Ag NPs@ZIF-8) and Ag NPs coating on ZIF-8 (Ag NPs-on-ZIF-8) were also investigated and it was found that Ag NPs/ZIF-8 possessed the best performance. Some experimental parameters including pH of the supporting electrolyte and scan rate were also investigated. Under optimal conditions, the proposed sensor exhibited excellent stability, reproducibility and selectivity for the determination of chloride ion with a wide linear detection range from 5 to 4000 μmol dm⁻³ and a low detection limit of 0.61 μmol dm⁻³ (S/N = 3). The proposed sensor was successfully applied to the determination of chloride ion spiked in human serum. All these results indicated that the developed Ag NPs/ZIF-8/GCE sensor was superior.

Thin Bi₂Se₃ flakes with few nanometer thicknesses and sized up to 350 μm were created by using electrochemical splitting from high-quality Bi₂Se₃ bulk monocrystals. The dependence of film resistance on the Bi₂Se₃ flake thickness demonstrates that, at room temperature, the bulk conductivity becomes negligible in comparison with the surface conductivity for films with thicknesses lower than 80 nm. Unexpectedly, all these films demonstrated p-type conductivity. The doping effect with sulfur or sulfur-related radicals during electrochemical exfoliation is suggested for the p-type conductivity of the exfoliated Bi₂Se₃ films. The formation of 2–8 nm films was predominantly found. Van der Waals (vdW) heterostructures of Bi₂Se₃/Graphene/SiO₂/Si were created and their properties were compared with that of Bi₂Se₃ on the SiO₂/Si substrate. The increase of the conductivity and carrier mobility in Bi₂Se₃ flakes of 3–5 times was found for vdW heterostructures with graphene. Thin Bi₂Se₃ films are potentially interesting for applications for spintronics, nano- and optoelectronics.

Nanoparticles of monoclinic WO₃ were synthesized by a facile method using Na₂WO₄ as raw material and PVP 70 000 (polyvinylpyrrolidone) as surfactant and template. The effect of PVP on the structure and photocatalytic activity of the synthesized WO₃ was discussed in detail. The prepared samples were characterized by XRD, SEM, FT-IR, UV–vis, XPS, PL techniques, and the results show that the visible light is strongly absorbed by the obtained samples, whose particle size varies from 38 to 85 nm. The photocatalytic properties of the resulted samples were evaluated using RhB in water as a target substance, and results illustrate that 30 mg l⁻¹ of RhB can be efficiently photodegraded by nano WO₃ under visible light irradiation. Based on the results of XPS, PL and photocalysis experiments, the reason of such improved photocatalytic efficiency may be attributed to the reducing activity of PVP, which leads to the formation of oxygen vacancies beneficial for the capture of photoelectrons and the generation of superoxide radicals. Furthermore, the results show that the photocatalytic efficiency is greatly influenced by the morphology of the synthesized WO₃ samples, and the WO₃ with a block-shaped morphology is an ideal photocatalyst for the degradation of RhB under visible light irradiation.

In this paper, we explore the impact of changing the growth conditions on the substrate surface during the metal-organic vapor phase epitaxy of 2D-transition metal dichalcogenides. We particularly study the growth of molybdenum disulfide (MoS₂) on sapphire substrates at different temperatures. We show that a high temperature leads to a perfect epitaxial alignment of the MoS₂ layer with respect to the sapphire substrate underneath, whereas a low temperature growth induces a 30° epitaxial alignment. This behavior is found to be related to the different sapphire top surface re-arrangement under H₂S environment at different growth temperatures. Structural analyses conducted on the different samples confirm an improved layer quality at high temperatures. MoS₂ channel-based metal–oxide–semiconductor field-effect transistors are fabricated showing improved device performance with channel layers grown at high temperature.

The ability of noble metal nanoparticles (NPs) to convert light into heat has triggered a lot of scientific interest due to the numerous potential applications, including, e.g. photothermal therapy or laser-based nanopatterning. In order for such applications to be practically implemented, the heating behaviour of NPs embedded in their surrounding medium has to be thoroughly understood, and theoretical models capable of predicting this behaviour must be developed. Here we propose a multiscale approach for modelling the photothermal response of a large ensemble of nanoparticles contained within a cm-scale, real-size container. Electromagnetic field, ray tracing and heat transfer simulations are combined in order to model the response of nanostars and nanospheres suspensions contained within a common Eppendorf tube. To validate the model, gold nanostars are then synthesised and characterized by electron microscopy and optical spectroscopy. Laser-induced heating experiments are conducted by irradiating colloid-filled Eppendorf tubes with a 785 nm continuous wave laser and monitoring by a thermographic camera. The experimental results confirm that the proposed model has potential for predicting and analysing the heating efficiency and temperature dynamics upon laser irradiation of plasmonic nanoparticle suspensions in real-scale containers, at cm³ volumes.

Metal-organic frameworks (MOFs) show possibilities to be potential candidates for proton exchange membranes (PEMs). However, the poor flexibility and processability of MOFs due to their crystalline nature limit their applications significantly. An efficient approach to overcome this limitation is to combine MOFs with polymers. In this work, novel lightweight and flexible Ni-MOFs/polyacrylonitrile nanofibers were fabricated by electrospinning. The nanofibers consisted of one-dimensional proton conduction channels for imidazole and show enhanced proton conductivity. A proton conductivity of 6.04 × 10⁻⁵ Scm⁻¹ was achieved at 363 K and 90% RH. Furthermore, the proton transport dynamics of the fibers were investigated using the AC impedance technique.

Exchange bias (EB) in ferromagnet/antiferromagnet bilayers, which has been extensively studied and applied for several decades, is sensitive to many factors such as layer thickness, texture and crystallization. Various factors in an antiferromagnet may counterbalance each other to limit and deteriorate EB. We used an unbiased Monte-Carlo method based on a modified Metropolis algorithm to predict that dependence of EB properties on antiferromagnetic anisotropy (K_AF) are highly improved by attaching a soft ferromagnet on the other side of the antiferromagnet. On one hand, target ferromagnet in trilayers displays a pronounced and stabilized EB plateau at high K_AF, on the contrary, EB is completely removed and instead a high coercivity is observed at low K_AF, exhibiting a roughly K_AF-modulated EB switching effect. On the other hand, EB is identified with no training in trilayers and well axially symmetric about antiferromagnetic easy axis. Meanwhile, in trilayers EB versus angle (θ) which is between antiferromagnetic easy axis and the direction of magnetic field is a roughly linear relationship in the intermediate θ range. Microscopic explorations found that a fully uncompensated magnetization in antiferromagnet may appear in trilayers and its rotatability is precisely controlled by K_AF, designating that the antiferromagnet/seed-ferromagnet bilayers resemble a ferromagnet with changeable hardness to induce a maximized coercivity of target ferromagnet at low K_AF to a maximized EB at high K_AF. Finally, a phenomenological model reveals that antiferromagnetic spins change from a fluctuated state to a blocked state due to the existence of seed ferromagnet, and thus in this work we conceived an artificial pinning layer to establish and regulate EB.

Molecular dynamics simulations are used to study the formation and development of interlayer dislocations in bilayer graphene (BLG) subjected to uniaxial tension. Two different BLGs are employed for the simulation: armchair (AC-BLG) and zigzag (ZZ-BLG). The atomic-level strains are calculated and the parameter 'dislocation intensity' is introduced to identify the dislocations. The interlayer dislocation is found to start at the edge and propagate to the center. For AC-BLG, the dislocations arise successively with the increase of applied strain, and all dislocations have the same width. For ZZ-BLG, the first dislocation arises alone. After that, two dislocations with different widths appear together every time. The simulated dislocation widths are in good agreement with existing experimental results. Across every dislocation, there is a transition from AB stacking to AC stacking, or vice versa. When temperature is taken into account, the dislocation boundaries become indistinct and the formation of dislocations is postponed due to the existence of dispersive small slippages. Due to the disturbance of temperature, dislocations present reciprocating movement. These findings contribute to the understanding of interlayer dislocations in two-dimensional materials, and will enable the exploration of many more strain related fundamental science problems and application challenges.

Two-dimensional materials such as hexagonal boron nitride (h-BN) and graphene have attracted wide attention in nanoelectronics and spintronics. Since their electronic characteristics are strongly affected by the local atomic structure, the heteroatom doping could allow us to tailor the electronic and physical properties of two-dimensional materials. In this study, a non-chemical method of heteroatom doping into h-BN under high-energy ion irradiation was demonstrated for the LiF/h-BN/Cu heterostructure. Spectroscopic analysis of chemical states on the relevant atoms revealed that 6% ± 2% fluorinated h-BN is obtained by the irradiation of 2.4 MeV Cu²⁺ ions with the fluence up to 10¹⁴ ions cm⁻². It was shown that the high-energy ion irradiation leads to a single-sided fluorination of h-BN by the formation of the fluorinated sp³-hybridized BN.

Inspired by natural photosynthesis, artificial heterojunction photocatalysts have been extensively studied. Herein, a novel ternary graphitic carbon nitride/platinum/bismuth vanadate (g-C₃N₄/Pt/BiVO₄) photocatalytic system was successfully synthesized, where Pt/BiVO₄ nanosheet is anchored on the surface of layered g-C₃N₄, as evidenced by structural observations. Ultraviolet photoelectron spectroscopy and ultraviolet–visible diffuse reflectance spectroscopy are carried out to identify the position of the conduction band and valence band. A Z-scheme is used to interpret the superior photocatalytic performance of g-C₃N₄/Pt/BiVO₄ and further verified by the capture of free radicals and terephthalic acid photoluminescence experiments. Compared with the g-C₃N₄/BiVO₄ binary system, the Z-scheme g-C₃N₄/Pt/BiVO₄ photocatalyst not only possesses enhanced carrier separation efficiency but also maintains sufficient redox properties, thus inducing superior photocatalytic activity. More importantly, the novel Z-scheme photocatalyst exhibits excellent recycle stability, which could provide inspiration for the rational design of efficient and practical photocatalysts for environmental pollution treatment. The ternary photocatalyst also exhibits significantly enhanced visible-light photocatalytic hydrogen production performance.

It is shown that the interplay between curvature and interfacial Dzyalonshinsky–Moriya interaction (DMI) is a pathway to ultrafast domain wall (DW) dynamics in ferromagnetic nanotubes. In this work, we theoretically study the effect that interfacial DMI has on the average velocity of a vortex DW in thin ferromagnetic nanotubes grown around a core composed of heavy atoms. Our main result shows that by delaying the Walker breakdown instability, the DW average velocity is of the order of 10³ m s⁻¹, which is greater than usual values for these systems. The remarkable velocities achieved through this configuration could greatly benefit the development of spintronic devices.

Improving Schottky diode characteristics in semiconducting devices is essential for better functionality in electronic and optoelectronic devices at nanoscale. In this paper, we investigate the electric transport characteristics of a gold (Au)-tip/n-Si-based nano-Schottky diode by using a conductive-mode atomic force microscope (CAFM). First, 10 nm average diameter Au nanoparticles (NPs) are monodispersed on the highly cleaned n-type Si substrate using an optimized spin-coating technique. The controlled and well dispersed NPs are confirmed by using the AC imaging mode of the AFM. The electrical characteristics are established by using an Au-coated AFM tip, by either soft engaging at the surface of the n-Si substrate or at the top of an individual Au NP. Landing of the AFM tip on the NP or n-Si substrate is validated by the force curves of the AFM. From the localized CAFM electrical characteristics, we observed the improvement in the figures of merit (FOM) that characterize the rectification performance including the (1-V) asymmetry (f_ASYM), and the turn-on voltage due to placing the Au NP between the AFM tip and n-Si substrate. These improved FOM of the nanoscale diodes are explained based on the increase in the tunneling current at the nanoscale Au-NP/n-Si interface. Moreover, the nanoscale control of interface structure is extremely important to improve the characteristics of nano-Schottky diodes.