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A series of (1-x) (BaO–TiO2–SiO2–Al2O3–B2O3)-xHfO2 (abbreviated as (1-x)BTSAB-xH) glass-ceramics were designed and prepared by traditional melt quenching and heat treatment method. The dielectric and energy storage properties of the glass-ceramics were studied systematically. The results of X-ray diffraction indicate that the main crystal phase of (1-x) BTSAB-xH glass-ceramics is BaTiO3. It should be noted that the addition of HfO2 can not only increase the dielectric constant, but also enhance the breakdown dielectric strength, resulting in high theoretical energy storage density. The max theoretical energy storage density can reach up to 7.07 J/cm3. The discharged energy storage density is 0.73 J/cm3 measured at 300 kV/cm @ room temperature. These results show that Hf doped barium titanate-based glass-ceramics are promising materials for application in dielectric capacitor with high energy storage density.

Strain-adjusting the band gap of MoS2 using patterned substrates to improve the photoelectric performance of MoS2 has gradually become a research hotspot in recent years. However, there are still difficulties in obtaining high-quality two-dimensional materials and preparing photodetectors on patterned substrates. To overcome this, a continuous multilayer MoS2 film was transferred to a patterned gallium nitride substrate (PGS) for the fabrication of photodetectors, and density functional theory calculations showed that the band gap of the MoS2 film increased and that the electron effective mass decreased due to the introduction of PGS. In addition, finite difference time domain simulation showed that the electric field in the MoS2 area on the PGS is enhanced compared with that on the flat gallium nitride substrate due to the enhanced light scattering effect of the PGS. The photoresponse of the MoS2/PGS photodetector at 460 nm was also enhanced, with Iph increasing by 5 times, R increasing by 2 times, NEP decreasing to 3.88 × 10-13 W/Hz1/2, and D* increasing to 5.6 × 108 Jones. Our research has important guiding significance in adjusting the band gap of MoS2 and enhancing the photoelectric performance of MoS2 photodetectors.

High-precision aspheric negative plastic lenses are widely used in optical systems owing to their excellent performance and ease of high-efficiency manufacturing. The imaging performance of the lens is difficult to control, because it is unable to perform optical measurements directly and is sensitive to manufacturing processing meanwhile. Generally, the imaging performance is guaranteed by a strict control of geometrical deviation, such as Peak-to-Valley (PV) and Root-Mean-Square (RMS). In this study, an optical ray-tracing algorithm with the measured geometrical deviation data is proposed to perform an imaging performance analysis correlated with geometrical deviation for the injection molded high-precision aspheric negative plastic lens. Taguchi experiments are applied to investigating the effect of processing parameters. The geometrical deviation of the convex surface is found to be an order of magnitude greater than that of the concave surface. The geometrical dimension of the concave surface is mainly determined by the machining precision of the mold cavity surface, whereas the convex surface dimension is mainly affected by the lens shrinkage. However, the imaging performance has a nonlinear correlation with the geometrical deviation. Modulation Transfer Function (MTF) and Spot Diagram are equivalently affected by the concave and convex geometrical deviations, and depend on the object field height. The effect of processing parameters on geometrical deviation and imaging performance is uncorrelated. Thus, the imaging performance should be simultaneously considered as a criterion as well as the geometrical deviation in the optimization of aspheric negative lens injection molding processing. The imaging performance prediction using an optical ray-tracing algorithm with the measured geometrical deviation data is instrumental to optimize the manufacturing processing.

In this study, marine microalgae Chlorella pyrenoidosa produced 186 ml H2/l under nitrogen deprivation in natural seawater, and adding 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU) to medium reduced the total volume of hydrogen production by 85%. This suggested water was the main electron donor for hydrogenase. An active starch accumulation was observed during the first two days in nitrogen deprivation. But the starch content in cell decreased only by 7% at the end of the hydrogen evolution stage. This was shown the absence of a large contribution of starch to the hydrogen production by C. pyrenoidosa in nitrogen deprivation. Different from the hydrogen production by Chlamydomonas reinhardtii under sulfur deprivation condition, the concentration of acetate in the medium decreased not only at the stage of oxygen consumption but also during the stage of hydrogen evolution by C. pyrenoidosa. Thus, acetate is involved not only in the establishment of anaerobiosis but also plays an important role in the production of hydrogen by C. pyrenoidosa as an exogenous electron donor.

x%Pt-Naf-CV (Pt-Nafion-Cyclic Voltammetry) catalysts with homogeneously distributed platinum nanoparticles and ultra-low Pt loading are successfully synthesized by using a facile potential cycling approach. The as-synthesized 0.8%Pt-Naf-CV catalyst exhibits an enhanced electrocatalytic activity for hydrogen evolution reaction (HER) in 0.5 M H2SO4 solution, which obtains a low overpotential of 34 mV at 10 mA cm−2. The linear sweep voltammetry (LSV) curve of 0.8%Pt-Naf-CV catalyst is almost consistent with that of commercial Pt/C. However, the 0.8%Pt-Naf-CV catalyst displays a more excellent stability and durability in comparison with commercial Pt/C. Besides, the Pt loading of Pt/C (Pt–10 wt%) is about 10 times that of 0.8%Pt-Naf-CV catalyst. The improved electrocatalytic performances are derived from the synergistic effects of Pt and Nafion. The Nafion plays a significant role as a dispersant, carrier and structure directing agent on the morphology and size of the Pt catalyst. This result contributes a promising method to enhance the catalytic activity and reduce the amount of Pt.

Targeting delivery of photosensitizers to mitochondria as the most sensitive cellular organelles to reactive oxygen species (ROS) by positively charged polymeric nanocarriers (NCs) is one of the useful methods for efficient photodynamic therapy (PDT). However, the NCs with positively charged mitochondria-targeting moieties are easily cleaned during circulation, restricting their in vivo applications. Herein, to address this issue and enhance in vivo PDT efficacy, we developed a sequential-targeting delivery system consisting of mitochondria-targeting micelles as the core prepared from the cationic amphiphilic copolymer for loading chlorin e6 (Ce6) and a tumor-targeting pH-dependent charge transformational layer as the shell obtained from 2,3-dimethylmaleic anhydride modified Biotin-PEG4000-NH2 (BioPEGDMA) via electrostatic interaction. Concealed by the anionic shell, the as-prepared NCs showed longer retention within the first stage of tumor-targeting. Then, the accumulated NCs conversed to positive charge in tumor extracellular microenvironment (pH ∼ 6.5), which could be more effectively internalized by tumor cells, and the re-exposed triphenylphosphonium (TPP) groups endowed their second-stage targetability to the mitochondria. In vivo experiments revealed that the Ce6-loaded NCs exhibited remarkable tumor inhibition rates of 84.1% and 93.2% on BALB/c nude mice and Kunming mice, respectively, under 660 nm NIR irradiation, and stimulated immune responses with upregulated expression of IFN-γ, TNF-α and CD3+ in tumor tissues, and enhanced activation of CD3+/CD4+, CD3+/CD8+ T lymphocytes and DCs in both tumor tissues and lymph glands. This work provided a new pathway for the development of smart drug delivery system with advanced PDT efficacy. Statement of significance Although the existing targeting delivery of photosensitizers to mitochondria by positively charged nanocarriers (NCs) have efficiently enhanced photodynamic therapy (PDT), their positive charges caused rapid clearance during circulation, which has restricted their in vivo applications. Therefore, we fabricated a novel sequential-targeting NC to solve the problem. The tumor accumulated NCs conversed to positive charge in tumor extracellular microenvironment, and the re-exposed triphenylphosphonium groups initiated second-stage targetability to mitochondria. This system exhibited remarkable tumor inhibition efficiency both in vitro and in vivo. Moreover, as we hypothesized, mitochondria-located PDT could promote immune response, resulting in improvement of PDT. The strategy of sequential targeting-based PDT in combination with augmented immune response showed a novel pathway for the development of smart drug delivery system with advanced PDT.

MoS2, as a typical representative of two-dimensional semiconductors, has been explored extensively in applications of optoelectronic devices because of its adjustable bandgap. However, to date, the performance of the fabricated photodetectors has been very sensitive to the surrounding environment owing to the large surface-to-volume ratio. In this work, we report on large-scale, high-performance monolayer MoS2 photodetectors covered with a 3-nm Al2O3 layer grown by atomic layer deposition. In comparison with the device without the Al2O3 stress liner, both the photocurrent and responsivity are improved by over 10 times under 460-nm light illumination, which is due to the tensile strain induced by the Al2O3 layer. Further characterization demonstrated state-of-the-art performance of the device with a responsivity of 16.103 A W−1, gain of 191.80, NEP of 7.96 × 10−15 W Hz−1/2, and detectivity of 2.73 × 1010 Jones. Meanwhile, the response rise time of the photodetector also reduced greatly because of the increased electron mobility and reduced surface defects due to the Al2O3 stress liner. Our results demonstrate the potential application of large-scale strained monolayer MoS2 photodetectors in next-generation imaging systems.

In this work, we synthesized a Pd nanonetwork (PdNN) catalyst by employing Nafion as structure-directing agent. The nanonetwork-like structure is interconnected by Pd particles. Moreover, the morphologies and the sizes of PdNN samples can be tunable by adjusting concentrations of Pd precursor. The as-prepared PdNN catalysts have superior hydrogen evolution reaction (HER) performance to that of commercial Pd/C. Among them, PdNN-4.5 catalysts exhibit the most excellent hydrogen evolution performance, which contains an overpotential of 59 mV at 10 mA cm-2 and a Tafel slope of only 54 mV dec-1. Besides, a super stability is also displayed for PdNN-4.5 catalysts. The significant improvement in the HER performance of the PdNN-4.5 catalyst may be attributed to the nanonetwork-like structure, the sizes, and the interaction between the Pd catalysts and Nafion. Thus, this work can provide a simple method for synthesizing the highly efficient Pd-based catalyst for HER.

Tumor multidrug resistance (MDR) is one of the main reasons for the failure of clinical chemotherapy. Here, a bio-responsive anti-drug-resistant polymer micelle that can respond to the reductive GSH in the tumor microenvironment (TME) for delivery of HCPT was designed. A new type of polymer with anti-drug resistance and anti-tumor effect was synthesized and used to encapsulated HCPT to form reduction-sensitive micelles (PDSAH) by a thin-film dispersion method. It is demonstrated that the micelle formulation improves the anti-tumor activity and biosafety of HCPT, and also plays a significant role in reversing the drug resistance, which contributes to inhibiting the tumor growth and prolonging the survival time of H22 tumor-bearing mice. The results indicate that this nanoplatform can serve as a flexible and powerful system for delivery of other drugs that are tolerated by tumors or bacteria.

Recombinase polymerase amplification (RPA) was combined with lateral flow to develop a gold nanoparticles test strip for point-of-care diagnosis of African swine fever virus (ASFV), which is called lateral flow gene assay (LFGA). Common diagnostic techniques, including polymerase chain reaction (PCR) and immunochromatography, are time-consuming and labor-intensive, and generally require costly instruments. For improvement, this assay used tailed primers to produce DNA duplexes with a single-stranded tail at one end which can hybridize with a gold nanoparticle (AuNP)-labeled oligonucleotide detection probe. And then, biotin attached to the other end of the product bound to streptavidin, which previously fixed to the test line. Therefore, there would form a sandwich structure, and gold nanoparticles labeled on the detection probe would show a red band on the test line of strip. With the low reaction temperature (37~42 °C) and short reaction time (30 min), LFGA can specifically identify ASFV in blood samples infected with ASFV and classical swine fever virus (CSFV), and the LOD was 102 copies/μL, which was comparable to that of agarose gel electrophoresis. In addition, blood samples infected with ASFV and CSFV were tested, and it was found that the LFGA can specifically identify ASFV DNA. In conclusion, LFGA achieves visual observation of the product after rapid RPA amplification and does not require any expensive instruments during the entire process, which is very helpful for early diagnosis of ASFV.

The creative integration of sp-hybridized carbon atoms into artificial carbon graphdiyne has led to graphdiyne with superior properties in terms of uniformly distributed pores, ambipolar carrier transport, natural bandgap, and broadband absorption. Consequently, graphdiyne, regarded as a promising carbon material, has garnered particular attention in light-matter interactions. Light-matter interactions play an important role in optical information technology and meet the increasing demand for various energy sources. Herein, the status and challenges in nonlinear photonic and optoelectronic applications of graphdiyne, which are still in the infancy stage, are summarized. Furthermore, the bottleneck and perspective of graphdiyne in these aspects are discussed. It is therefore anticipated that this review could promote the development of graphdiyne in photonic and optoelectronic fields.

Laser-ablated group 6 transition metal atoms react with BF3 to yield typical transition metal inserted complexes F2B-MF (M = Cr, Mo, and W) and terminal borylene complex FBWF2. These products are investigated by using infrared spectroscopy, isotopic substitution and theoretical frequency calculations. The inserted complexes F2B–MF (M = Cr, Mo, and W) were identified by antisymmetric and symmetric stretching modes of F–B–F. The FBWF2 molecule has a 11B–F (10B–F) stretching frequency at 1453.2 (1505.0) cm−1 and the triple bond between boron and tungsten is confirmed by EDA-NOCV calculations, CASSCF calculation and NBO analysis. Furthermore, the bonding for tungsten complexes is compared with that of molybdenum and chromium complexes, which reveals interesting differences in their chemistries.

We investigate the gaseous ScO(H2O)1–3Ar+ cations prepared by laser vaporization coupled with supersonic molecular beam using infrared photodissociation spectroscopy in the O–H stretching region. The cation structures are characterized by comparing the experimentally observed frequencies with the simulated vibration spectra. We reveal that stoichiometric ScO(H2O)Ar+ is intrinsically the hydrated oxide cation expressed as H2O–ScOAr+ hydrate rather than Sc(OH)2Ar+ dihydroxide, although the former is higher in energy by 29.5 kcal mol−1 than the latter. Interestingly, when more water molecules are introduced to the complex, we find that the stoichiometric ScO(H2O)2–3Ar+ embraces the core subunit of Sc(OH)2+. Theoretical calculations suggest that the energy barrier of hydrogen transfer plays a critical role in the isomerization from hydrated complex to dihydroxide. When more than one water molecule is involved in the complex, the hydrogen transfer becomes nearly barrierless through a six-member cyclic transition state, leading to the reduction in the energy barrier from 21.8 kcal mol−1 to 4.2 kcal mol−1. Altogether, we conclude that the solvent molecules such as water can decrease the energy barrier and thus induce the formation of hydroxy species in the hydrolysis process.

A nanofabrication method for the production of ultra-dense planar metallic nanowire arrays scalable to wafer-size is presented. The method is based on an efficient template deposition process to grow diverse metallic nanowire arrays with extreme regularity in only two steps. First, III–V semiconductor substrates are irradiated by a low-energy ion beam at an elevated temperature, forming a highly ordered nanogroove pattern by a “reverse epitaxy” process due to self-assembly of surface vacancies. Second, diverse metallic nanowire arrays (Au, Fe, Ni, Co, FeAl alloy) are fabricated on these III–V templates by deposition at a glancing incidence angle. This method allows for the fabrication of metallic nanowire arrays with periodicities down to 45 nm scaled up to wafer-size fabrication. As typical noble and magnetic metals, the Au and Fe nanowire arrays produced here exhibited large anisotropic optical and magnetic properties, respectively. The excitation of localized surface plasmon resonances (LSPRs) of the Au nanowire arrays resulted in a high electric field enhancement, which was used to detect phthalocyanine (CoPc) in surface-enhanced Raman scattering (SERS). Furthermore, the Fe nanowire arrays showed a very high in-plane magnetic anisotropy of approximately 412 mT, which may be the largest in-plane magnetic anisotropy field yet reported that is solely induced via shape anisotropy within the plane of a thin film.

Compared with conventional injection molding, injection-compression molding can mold optical parts with higher precision and lower flow residual stress. However, the melt flow process in a closed cavity becomes more complex because of the moving cavity boundary during compression and the nonlinear problems caused by non-Newtonian polymer melt. In this study, a 3D simulation method was developed for injection-compression molding. In this method, arbitrary Lagrangian- Eulerian was introduced to model the moving-boundary flow problem in the compression stage. The non-Newtonian characteristics and compressibility of the polymer melt were considered. The melt flow and pressure distribution in the cavity were investigated by using the proposed simulation method and compared with those of injection molding. Results reveal that the fountain flow effect becomes significant when the cavity thickness increases during compression. The back flow also plays an important role in the flow pattern and redistribution of cavity pressure. The discrepancy in pressures at different points along the flow path is complicated rather than monotonically decreased in injection molding.

Two-dimensional thin layers of indium selenide (InSe) have attracted much attention due to their potential applications in optoelectronics as highly responsive photo-detectors and field-effect transistors. In the present work, we explore thermal properties of InSe thin layers on a high-k substrate with a thin SiO2 passivation layer using temperature and power dependent Raman spectroscopy. The first order temperature coefficients for in-plane (E12g) and out-of-plane (A21g) modes of InSe few-layers on a Al2O3 substrate were found to be −0.00507 and −0.00310 cm−1/K, respectively, which are much smaller than the corresponding values −0.00612 and −0.00528 cm−1/K of similarly prepared sample on SiO2 substrate. The difference in temperature coefficients is attributed to compressive strain introduced by the Al2O3. Further, the average thermal conductivity of a 4 nm thin InSe layer on the Al2O3 substrate at room temperature was found to be ∼53.4 W/m-K, which is significantly larger than those of InSe layers prepared on SiO2 substrate (∼28.7 W/m-K). The existed interface charges between the Al2O3 and InSe layers cause the observed improvement of thermal conductivity by electron-phonon interactions.

Current challenge of using cytokines is its poor distribution and systemic side effects. To avoid this issue, we prepared the tumor-targeted and microenvironment-responsive nanocarriers (TRN), which were consisted of α-tocopheryl succinate (α-TOS) loaded mesoporous silica nanoparticles as cores, and surface-modified by thioketal-linkage, electrostatically coated with carboxymethyl chitin, and further anchored glucose-regulated protein 78-binding peptide as shells for encapsulating IL-12. TRN showed a size of 260 nm after encapsulated IL-12 and α-TOS with loading content of 0.0206% and 7.21%, respectively, and exhibited good biocompatibility to 4 T1 cells and macrophages. Moreover, IL-12/α-TOS loaded TRN displayed obvious anti-tumor efficacy on BALB/c nude mice bearing 4 T1 tumors, which was derived from promoted targeting to tumor tissue, endocytosed by macrophages and locally release IL-12 to subsequently repolarize tumor-associated macrophages into tumoricidal M1 phenotype with reduced side effects. The nanosystem exhibited as a promising strategy with functional conversion of macrophages in tumor microenvironment for anti-tumor therapy.

Cross-sectional Raman spectroscopy is used to characterize the defect formation and the defect recovery in MeV H+ implanted bulk GaN and 4H-SiC in the high energy MeV ion-cut process. The Raman intensity decreases but the forbidden modes are activated at the damage region, and the intensity decrease is proportional to the damage level. The Raman spectrum is quite sensitive to detect the damage recovery after annealing. The main peak intensity increases and the forbidden mode disappears in both annealed GaN and 4H-SiC samples. The Raman spectra of GaN samples annealed at different temperatures suggest that higher annealing temperature is more efficient for damage recovery. While, the Raman spectra of SiC indicate that higher implantation temperature results in heavier lattice damage and other polytype clusters might be generated by high annealing temperature in the annealed SiC samples. The cross-sectional Raman spectroscopy is a straightforward method to characterize lattice damage and damage recovery in high energy ion-cut process. It can serve as a fast supplementary measurement technique to Rutherford backscattering spectrometry (RBS), nuclear reaction analysis (NRA) and transmission electron microscope (TEM) for the defect characterizations.

This letter presents an experimental capacitance–voltage ${C}$ – ${V}$ analysis for Si p-tunnel FETs (TFETs) fabricated on ultrathin body at various frequencies and temperatures. The capacitance distribution in TFETs is quite different compared with MOSFETs, due to different inversion charges partitioning between source and drain. Contrary to predictions from simulations, we provide experimental evidence for the first time that the contribution of the gate-to-source capacitance ${C}_{\textsf {gs}}$ to the total gate capacitance is much larger than expected, and even comparable to the gate-to-drain capacitance ${C}_{\textsf {gd}}$ at higher ${V}_{\textsf {ds}}$ and ${V}_{g}$ . Comparable values of ${C}_{\textsf {gs}}$ and ${C}_{\textsf {gd}}$ would imply that the Miller capacitance effect in TFETs-based circuits is less pronounced as predicted in simulations.

Uniform and highly oriented NiSi0.8Ge0.2 layer is achieved by using a Ti interlayer during Ni germanosilicidation. Compared with the reference sample, the morphology of the grown Ni(Si0.8Ge0.2) layer with a Ti interlayer is improved with a better uniformity and smoother surface and interface. The Ni(Si0.8Ge0.2) layer is highly oriented grown on Si0.8Ge0.2 substrate at 500 °C annealing in the case of 5 nm Ti interlayer, with the preferred orientation relationships of (010) Ni(Si0.8Ge0.2) || (001) Si0.8Ge0.2 and (101) Ni(Si0.8Ge0.2) || (110) Si0.8Ge0.2. In addition, most of Ti atoms from the original interlayer diffuses toward the surface after annealing. The reduced Ni diffusion is conducive for the uniform reaction between Ni and Si0.8Ge0.2, resulting in highly oriented Ni(Si0.8Ge0.2) grown on Si0.8Ge0.2.

We present a systematic study on the effects of CF4 plasma immersion ion implantation (PIII) in Si on the phase evolution of ultra-thin Ni silicides. For 3 nm Ni, NiSi2 was formed on Si substrates with and without CF4 PIII at temperature as low as 400 °C. For 6 nm Ni, NiSi was formed on pure Si, while epitaxial NiSi2 was obtained on CF4 PIII Si. The incorporation of C and F atoms in the thin epitaxial NiSi2 significantly reduces the layer resistivity. Increasing the Ni thickness to 8 nm results in the formation of NiSi, where the thermal stability of NiSi, the NiSi/Si interface and Schottky contacts are significantly improved with CF4 PIII. We suggest that the interface energy is lowered by the F and C dopants present in the layer and at the interface, leading to phase evolution of the thin Ni silicide.

The abilities to fabricate wafer scale single crystalline oxide thin films on metallic substrates and to locally engineer their resistive switching characteristics not only contribute to the fundamental investigations of the resistive switching mechanism but also promote the practical applications of resistive switching devices. Here, wafer scale LiNbO3 (LNO) single crystalline thin films are fabricated on Pt/SiO2/LNO substrates by ion slicing with wafer bonding. The lattice strain of the LNO single crystalline thin films can be tuned by He implantation as indicated by XRD measurements. After He implantation, the LNO single crystalline thin films show self-rectifying filamentary resistive switching behaviors, which is interpreted by a model that the local conductive filaments only connect/disconnect with the bottom interface while the top interface maintains the Schottky contact. Thanks to the homogeneous distribution of defects in single crystalline thin films, highly reproducible and uniform self-rectifying resistive switching with large on/off ratio over four order of magnitude was achieved. Multilevel resistive switching can be obtained by varying the compliance current or by using different magnitude of writing voltage.

Owing to their high intrinsic thermal conductivity (~2.0 W/mK), cellulose nanocrystals (CNCs) have a high potential for use as thermal management materials in modern electronics. The incorporation of a nanofiller with a high thermal conductivity, such as h-boron nitride (h-BN) and graphene (Gr), is a common approach to improve the thermal properties. However, the thermal transport across the filler–matrix interface is not well understood considering the existence of amphiphilic surfaces in the CNCs. In this study, the interfacial thermal conductance (ITC) between the hydrophobic or hydrophilic surfaces of the CNCs and h-BN was systematically investigated using molecular dynamic simulations. The hydrophobic surface exhibited the highest ITC, and the ITC for ordered CNCs was higher than that for the amorphous cellulose. The ITCs of h-BN/CNCs were higher than those of Gr/CNCs. The underlying mechanisms were explained by the interfacial adhesion strength and phonon vibration power spectrum. Additionally, the overall thermal performances of the CNCs/h-BN nanocomposites were investigated through the effective medium theory and simulation results. Although the inherent thermal conductivity of h-BN was lower than that of Gr, because of the dominant effect of the ITC on the heat transfer in the nanocomposites, h-BN with a higher ITC may increase the thermal conductivity of the CNCs more than Gr.

2D III-nitride materials have been receiving considerable attention recently due to their excellent physicochemical properties, such as high stability, wide and tunable bandgap, and magnetism. Therefore, 2D III-nitride materials can be applied in various fields, such as electronic and photoelectric devices, spin-based devices, and gas detectors. Although the developments of 2D h-BN materials have been successful, the fabrication of other 2D III-nitride materials, such as 2D h-AlN, h-GaN, and h-InN, are still far from satisfactory, which limits the practical applications of these materials. In this review, recent advances in the properties, growth methods, and potential applications of 2D III-nitride materials are summarized. The properties of the 2D III-nitride materials are mainly obtained by first-principles calculations because of the difficulties in the growth and characterizations of these materials. The discussion on the growth of 2D III-nitride materials is focused on 2D h-BN and h-AlN, as the developments of 2D h-GaN and h-InN are yet to be realized. Therefore, applications have been realized mostly based on the 2D h-BN materials; however, many potential applications are cited for the entire range of 2D III-nitride materials. Finally, future research directions and prospects in this field are also discussed.

Strain engineering has been reported to improve the optical and electrical properties of two-dimensional materials, and the adjustable bandgap of MoS2 has great application value in strain engineering. In this work, to explore the influence of the Si3N4 stress liner on the MoS2 photodetector, plasma enhanced chemical vapor deposition was used to deposit a 5 nm Si3N4 film on the surface of the device to introduce strain. The simulation results show that there is tensile strain in the MoS2 area under a Si3N4 layer, which can decrease the bandgap and electron effective mass of MoS2. The measurement results of the device show that the Si3N4 stress liner devices exhibit a higher light response than the Al2O3/MoS2/sapphire photodetector (control devices) under 365 and 460 nm laser illuminations. The maximum photocurrent ( I p h) and responsivity (R) of the stress liner device under 365 nm illumination are 4.1 mA and 739.9 A/W, respectively, which are more than 30 times the corresponding value of the control device. Also, the maximum specific detectivity (D*) reached 2.5 × 1011 Jones, and the lowest noise equivalent power is 8.7 × 10−16 W/Hz1/2. Our work proved the feasibility of the Si3N4 stress liner to improve the performance of MoS2 photodetectors.

We present the experimental analysis of planar Si p-tunnel FETs (TFETs) fabricated on ultrathin body Silicon on Insulator (SOI) substrates by an optimized dopant implantation into silicide process. The average subthreshold swing of such planar TFETs reaches 75 mV/decade over four orders of magnitude of drain current. Emphasis is placed on the capacitance–voltage analysis of TFETs. In contrast to simulation predictions, we provide experimental evidence that the contribution of $C_{\mathrm {gs}}$ to the total gate capacitance increases at on-state, which in turn results in a decrease of the gate-to-drain capacitance $C_{\mathrm {gd}}$ . This beneficial effect could result in a reduction of the Miller capacitance effect in TFETs-based circuits.

The phase equilibria of the Co–Ni–Zr ternary system at 1 000 °C, 1 100 °C and 1 200 °C were experimentally investigated by means of back-scattered electron imaging, electron probe microanalysis and X-ray diffraction on the equilibrated ternary alloys. In this study, no ternary compound is found. The (αCo, Ni) phase region extends from the Ni-rich corner to the Co-rich corner with small solubility of Zr at three sections. At 1 000 °C and 1 100 °C, Ni5Zr, Co2Zr and Ni10Zr7 phases have large solid solution ranges, but Ni10Zr7 phase disappears at 1 200 °C. The Ni7Zr2, NiZr, Co11Zr2, Co23Zr6 and CoZr phases exhibit nearly linear compounds in the studied sections, and have large composition ranges. Additionally, some differences in phase relationship exist among the above three isothermal sections.

An ion-sensitive field-effect transistor (ISFET) with improved sensing current and voltage sensitivity is realized by using a sSi/Si0.5Ge0.5/sSOI quantum-well (QW) heterostructure and an Al2O3 dielectric layer as sensing membrane coupling with the back-gate. The voltage sensitivity is much higher than the reference SOI ISFET, typically at low drain current due to the high hole mobility confined in the SiGe QW. A high voltage sensitivity 360mV/pH with a linearity of 99.89% was achieved for QW ISFET. The results of the planar QW ISFET show great potential for low cost, real-time monitoring of bio-chemicals due to its simplified process. Display Omitted sSi/Si0.5Ge0.5/sSOI (QW) ISFETs were fabricated and experimentally investigated for the first time.A high voltage sensitivity 360mV/pH with very good linearity has been achieved with QW ISFET.Compared with SOI devices, QW ISFETs show higher voltage sensitivity of small signals at smaller drain currents.

Three isothermal sections of the Ni–Fe–Zr ternary system at 1000, 1100, and 1200 °C were experimentally determined using equilibrated ternary alloys. No ternary compound is found in this system. The obtained experimental results show that among three isothermal sections, the (γFe, Ni) phase region extends from the Ni-rich corner to the Fe-rich corner, and the solubility of Zr in the (γFe, Ni) phase is small. The phase equilibrium at 1100 °C is similar to that at 1000 °C. The Ni5Zr, Ni10Zr7, and Fe2Zr phases have solid solution composition ranges, but the Ni7Zr2, Ni21Zr8, NiZr, NiZr2, and Fe23Zr6 phases almost exhibit nearly linear compounds both at 1000 and 1100 °C. The solubilities of Fe in Ni7Zr2 phase and Ni in Fe2Zr phase are extremely large. At 1200 °C, the liquid phase of Zr-rich corner forms the continuous region from the Ni–Zr side to the Fe–Zr side. Additionally, the solubilities of Fe in Ni5Zr, NiZr phases and Ni in Fe23Zr6 phase clearly increase with increasing temperature to 1200 °C. The obtained results may provide a better understanding of microstructures and further development of the Ni–Fe–Zr alloys.

The reaction of laser-ablated vanadium, niobium and tantalum atoms with hydrogen sulfide has been investigated using matrix isolation FTIR and theoretical calculations. The metal atoms inserted into the H−S bond of H2S to form the HMSH molecules (M=V, Nb,Ta), which rearranged to H2MS molecules on annealing for Nb and Ta. The HMSH molecule can also further react with another H2S to form the H2M(SH)2 molecules. These new molecules were identified on the basis of the D2S and H234S isotopic substitutions. DFT (B3LYP and BPW91) theoretical calculations are used to predict energies, geometries, and vibrational frequencies for these novel metal dihydrido complexes and molecules. Reaction mechanism for formation of group V dihydrido complex was investigated by DFT internal reaction coordinate calculations. The dissociation of HVSH gave VS+H2 on broad band irradiation and reverse reaction happened on annealing. Based on B3LYP calculation releasing hydrogen from HVSH is endothermic only by 13.5 kcal/mol with lower energy barrier of 16.9 kcal/mol.

A new nanosystem was prepared by coating ROS-cleavable thioketal (TK) bonded hollow mesoporous silica nanoparticles with carboxymethyl chitin via electrostatic interaction and further surface-anchored with glucose-regulated protein 78 binding peptide for targeted-delivery of doxorubicin (DOX) and α-tocopheryl succinate (α-TOS). The nanosystem (HMSN-TK-CMCH-GRP78P) showed an average size of 265 nm after loading DOX and α-TOS with a drug loading content of 4.06 % and 7.64 %, respectively. The in vitro release studies revealed the pH/ROS dual-responsibility of DOX/α-TOS loaded HMSN-TK-CMCH-GRP78P. The released α-TOS increased the intracellular ROS concentration, which could induce the cleavage of TK linkages and in turn accelerate DOX release. Moreover, the nanosystem could target to 4T1 cells, causing cell death in vitro and suppress tumor growth in vivo in 4T1-bearing BALB/c mice with reduced side effects, which illustrated that the nanosystem led to an effective anti-tumor efficacy and exhibited as a promising carrier to deliver chemotherapeutic agents for chemotherapy.

Layered tin disulfide (SnS2) nanosheets are gradually coming into people’s vision as an emerging two-dimensional material for the potential application majority in optoelectronic field. We investigate a sample of ultra-thin SnS2 nanosheets (∼5 nm) on SiO2/Si substrates and the photodetectors performance based on it with and without high-k ALD-Al2O3 stress liner. By means of temperature-dependent Raman spectroscopy, both a red-shift of Raman frequency from 313.1 cm−1 to 311.2 cm−1 as well as a reduction of the first order temperature coefficient from −0.01232 cm−1/K to −0.00895 cm−1/K are measured. For device, compared to SnS2 photodetector, Al2O3/SnS2 photodetector shows enhancement with 7-times light current, 10-times responsivity, 25%-off rising time and 70%-off falling time under 365 nm illumination. The phenomena can be rationalized by factors that the SnS2 sample suffers a tensile strain and passivation effect exerted by capped Al2O3 layer. Meanwhile, the first principle calculations assist the study from an angle of verification. The analogue stress treatment operated in this work improves the properties of SnS2 and enhances the performances of SnS2-based photodetectors, aiming at expanding the thin-film materials applications in optoelectronic devices.

Polymer orientation is a fundamental and key issue, exhibiting crucial impacts on physical properties of polymeric parts. Current methods are limited in transparent materials and fail to measure the dynamic orientation in industrial polymer processing in situ. Herein, we reported an innovative strategy that dynamic orientation for polymer molecular chains was successfully characterized in situ by dielectric method. A key dielectric-orientation theoretical model was established, and a facile interdigital electrode capacitor (IDEC) array sensor was designed. The experimental results not only agreed well with the classic elastic dumbbell model and the traditional optical measurement method, but also showed a universal applicability for different polymer solutions and a good application prospect in injection molding process. Investigated results showed that the orientation difference of 1 wt% PVDF/DMF, 1 wt% PVC/DMF and 1 wt% PS/DMF solution was 0.57, 0.97 and 0.75 at shear rate 0–407 1/s, respectively. Additionally, the method was successfully applied in injection molding (Δe, 0.25–0.88 under shear rate 56.6–250 1/s). Our strategy built a new ‘decoding fingerprint’ to the dynamic orientation of polymer.

Strain regulation as an effective way to enhance the photoelectric properties of two-dimensional (2D) transition metal dichalcogenides has been widely employed to improve the performance of photovoltaic devices. In this work, tensile strain was introduced in multilayer MoS 2 grown on GaN by depositing 3 nm of Al 2 O 3 on the surface. The temperature-dependent Raman spectrum shows that the thermal stability of MoS 2 is improved by Al 2 O 3 . Theoretical simulations confirmed the existence of tensile strain on MoS 2 covered with Al 2 O 3 , and the bandgap and electron effective mass of six layers of MoS 2 decreased due to tensile strain, which resulted in an increase of electron mobility. Due to the tensile strain effect, the photodetector with the Al 2 O 3 stress liner achieved better performance under the illumination of 365 nm wavelength, including a higher responsivity of 24.6 A/W, photoconductive gain of 520, and external quantum efficiency of 8381%, which are more than twice the corresponding values of photodetectors without Al 2 O 3 . Our work provides an effective technical way for improving the performance of 2D material photodetectors.

Gratings, one of the most important energy dispersive devices, are the fundamental building blocks for the majority of optical and optoelectronic systems. The grating period is the key parameter that limits the dispersion and resolution of the system. With the rapid development of large X-ray science facilities, gratings with periodicities below 50 nm are in urgent need for the development of ultrahigh-resolution X-ray spectroscopy. However, the wafer-scale fabrication of nanogratings through conventional patterning methods is difficult. Herein, we report a maskless and high-throughput method to generate wafer-scale, multilayer gratings with period in the sub-50 nm range. They are fabricated by a vacancy epitaxy process and coated with X-ray multilayers, which demonstrate extremely large angular dispersion at approximately 90 eV and 270 eV. The developed new method has great potential to produce ultrahigh line density multilayer gratings that can pave the way to cutting edge high-resolution spectroscopy and other X-ray applications., Fabrication of wafer-scale nanogratings for X-ray spectroscopy is difficult especially for very high line densities. The authors use vacancy epitaxy to fabricate sub-50-nm-periodicity gratings, coated with multilayers for efficient operation, for use in ultra-high resolution x-ray spectroscopy.

The energy band alignment at the multilayer-MoS2/ZrO2 interface and the effects of CHF3 plasma treatment on the band offset were explored using x-ray photoelectron spectroscopy. The valence band offset (VBO) and conduction band offset (CBO) for the MoS2 /ZrO2 sample is about 1.87 eV and 2.49 eV, respectively. While the VBO was enlarged by about 0.75 eV for the sample with CHF3 plasma treatment, which is attributed to the up-shift of Zr 3d core level. The calculation results demonstrated that F atoms have strong interactions with Zr atoms, and the valence band energy shift for the d-orbital of Zr atoms is about 0.76 eV, in consistent with the experimental result. This interesting finding encourages the application of ZrO2 as gate materials in MoS2-based electronic devices and provides a promising way to adjust the band alignment.

Ultrasonic sparse array which derived from phased array can control the aperture and overcome local area detection. It has simple configuration and has characteristics of large scanning range and high detection accuracy, which is one of the most promising applications of ultrasonic nondestructive testing technology. Scattering wave received by sparse array includes useful information of defects, such as location, shape and specific characteristics. However, scattering guided wave with multimode behavior will increasing complexity of scattering patterns. Methods using multi-mode signals are more adaptable than using single mode signals which generated by special transducer array. In order to utilize scattering coefficient matrix (SCM) method for defects identification, multi-mode separation technique is applied. This paper proposed a Multi-Objects Artificial Bee Colony (MOABC) method to separate modes and reconstruct SCM. First, sparse array signals are decomposed into different modes under a strategy of multi parameter objects optimization, which cannot achieved by means of traditional mode separation method only using symmetry for SCM. MOABC is then modified to improve boundary conditions of food source and enlarging changing elements of parameter vector for onlooker bees. Finally, mode separation is achieved and reconstructed mode is used to for new SCM. Sparse array guided wave is applied to homogeneous materials with through-hole defect. Both simulation and experiment results are discussed. Results show that MOABC algorithm can estimate characteristic parameters more accurate and more adaptable to reconstruct scattering coefficient matrix without symmetry.

We demonstrate an effective way to improve the thermal stability of nickel stanogermanide (NiGeSn) by incorporating platinum (Pt) interlayer. After Ni/Pt/GeSn samples reacted at different temperatures (300°C–500°C), we obtained uniform NiGeSn films. By means of sheet resistance measurement, scanning electron microscopy, cross-sectional transmission electron microscopy and energy dispersive X-ray spectroscopy characterization. These results show that in the existence of Pt, the applicable annealing temperature of NiGeSn is broadened and the morphology of the NiGeSn film is smoother and more uniform.

In this work, a comprehensive study of the bias temperature instability (BTI) degradation has been performed on SOI MOSFETs with various gate lengths (from 30 nm to 150 nm). For both nMOSFETs and pMOSFETs, the BTI degradation is alleviated when the gate length decreases. A new model was proposed to explain the observed gate length dependence of the BTI degradation. The decrease in the BTI degradation of MOSFETs with shorter gate length is caused by the decrease in normal electric field across the interface of Si-dielectric, which was concept-proofed by TCAD simulations.

High-energy ion slicing is promising to produce the free-standing GaN films with thickness in the range of 10–20 µm, which would promote the mass applications of GaN substrates. In this paper, bulk GaN was implanted by 1.6 MeV H ions with the mean projected range Rp of around 17 μm and the thermal evolution of the H-induced defects was investigated in detail. Due to the migration-coalescence mechanism, the H-induced point defects gather to form the initial cavity defects which grow up via the Ostwald ripening mechanism. The cavity defect distribution is determined by the distributions of the implanted hydrogen and the implantation-induced damages. The area ratio of cavity defects in the center damage band of the 1.6 MeV sample was around 3.4%. Annealing at higher temperature enhances the defect migration and recovery. Larger H ion fluence or higher annealing temperature is required to accomplish the exfoliation of a free-standing GaN thick film.

Die-to-wafer heterogeneous integration of single-crystalline GaN film with CMOS compatible Si(100) substrate using the ion-cutting technique has been demonstrated. The thermodynamics of GaN surface blistering is in-situ investigated via a thermal-stage optical microscopy, which indicates that the large activation energy (2.5 eV) and low H ions utilization ratio (~6%) might result in the extremely high H fluence required for the ion-slicing of GaN. The crystalline quality, surface topography and the microstructure of the GaN films are characterized in detail. The full width at half maximum (FWHM) for GaN (002) X-ray rocking curves is as low as 163 arcsec, corresponding to a density of threading dislocation of 5 × 107 cm−2. Different evolution of the implantation-induced damage was observed and a relationship between the damage evolution and implantation-induced damage is demonstrated. This work would be beneficial to understand the mechanism of ion-slicing of GaN and to provide a platform for the hybrid integration of GaN devices with standard Si CMOS process.

The physicochemical properties of whole wheat starch and its A-Type and B-Type granules isolated from frozen dough at 0, 4 and 8 weeks of storage were investigated. Results showed that profiles of A-Type granules were more or less constant while significant differences of B-Type granules involving in irregular edges, increased relative crystallinities and decreased Viscosities were observed after 8 weeks of storage, suggesting that B-Type granules were more sensitive to freezing. These were mainly attributed to the release of leaching materials from starches, resulting in the ratio of amylose to amylopectin, protein and lipid content decreased by 25.93%, 12.05% and 31.65%, respectively. Whole wheat starch remained essentially unchanged during freezing. It seemed that B-Type granules, as a small part of whole wheat starch, had less influence on whole wheat starch than A-type granules in spite of their significant deterioration upon storage.

Ion-cutting of piezoelectric LiNbO3 (LN) thin film provides a material platform for the design and fabrication of novel integrated photonics and RF MEMS devices. In this paper, the ion-slicing mechanisms of He-implanted LN with different orientations are investigated. The anisotropy of film exfoliation is observed on LN wafers with different orientations. The Z-cut LN shows regular surface blistering and “plate-like” exfoliation, while the Y-cut LN shows the unique “rolled-up” exfoliation. Two types of defect, i.e. the pressure-related plateau defect and the stress-related crack defect, are observed to contribute to the film exfoliation. Moreover, the defect evolution in H-implanted LN is investigated. In comparison with the He-implanted LN, implanted H ions are mainly trapped by O-H bond and the implantation-induced strain is not strong enough, which are inadequate to form the continuous crack. Therefore the H ions are not favorable for the mass production of LNOI substrates.

Black phosphorus (BP) has emerged as a promising two-dimensional (2D) material for next generation transistor applications due to its superior carrier transport properties. Among other issues, achieving reduced subthreshold swing and enhanced hole mobility simultaneously remains a challenge which requires careful optimization of the BP/gate oxide interface. Here, we report the realization of high performance BP transistors integrated with HfO2 high-k gate dielectric using a low temperature CMOS process. The fabricated devices were shown to demonstrate a near ideal subthreshold swing (SS) of ~69 mV/dec and a room temperature hole mobility of exceeding >400 cm2/Vs. These figure-of-merits are benchmarked to be the best-of-its-kind, which outperform previously reported BP transistors realized on traditional SiO2 gate dielectric. X-ray photoelectron spectroscopy (XPS) analysis further reveals the evidence of a more chemically stable BP when formed on HfO2 high-k as opposed to SiO2, which gives rise to a better interface quality that accounts for the SS and hole mobility improvement. These results unveil the potential of black phosphorus as an emerging channel material for future nanoelectronic device applications.

Integration of high quality single crystalline InP thin film on Si substrate has potential applications in Si-based photonics and high-speed electronics. In this work, the exfoliation of a 634 nm crystalline InP layer from the bulk substrate was achieved by sequential implantation of He ions and H ions at room temperature. It was found that the sequence of He and H ion implantations has a decisive influence on the InP surface blistering and exfoliation, which only occur in the InP pre-implanted with He ions. The exfoliation efficiency first increases and then decreases as a function of H ion implantation fluence. A kinetics analysis of the thermally activated blistering process suggests that the sequential implantation of He and H ions can reduce the InP thin film splitting thermal budget dramatically. Finally, a high quality 2 inch InP-on-Si(100) hetero-integration wafer was fabricated by He and H ion sequential implantation at room temperature in combination with direct wafer bonding.

SiC is a widely used wide-bandgap semiconductor, and the freestanding ultrathin single-crystalline SiC substrate provides the material platform for advanced devices. Here, we demonstrate the fabrication of a freestanding ultrathin single-crystalline SiC substrate with a thickness of 22 μm by ion slicing using 1.6 MeV H ion implantation. The ion-slicing process performed in the MeV energy range was compared to the conventional case using low-energy H ion implantation in the keV energy range. The blistering behavior of the implanted SiC surface layer depends on both the implantation temperature and the annealing temperature. Due to the different straggling parameter for two implant energies, the distribution of implantation-induced damage is significantly different. The impact of implantation temperature on the high-energy and low-energy slicing was opposite, and the ion-slicing SiC in the MeV range initiates at a much higher temperature.