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To overcome the limitations of both LDHs and MXenes, we develop a self-sacrifice template strategy using a zeolite imidazolate framework-67 (ZIF-67) to derive Co-LDH anchored on an MXene conductive substrate (Co-LDH/MXene). In this process, ZIF-67 grows on the MXene nanosheets, then spontaneously transforms into Co-LDH/MXene in aqueous solution at room temperature. As the LIB anode, it shows a reversible capacity of 854.9 and 398.0 mAh g -1 at 0.1 and 1 A g -1 , respectively. This work proposes a feasible synthesis method for the in situ construction of a Co-LDH/MXene hybrid, which may be suitable for other MXenes.

A hydrogel based on titanium dioxide/MXene with polyvinyl alcohol/graphene oxide (TiO 2 /MXene-PVA/GO) composite was successfully formulated and applied to modify a screen-printed carbon electrode (SPCE) for urinary norepinephrine (NE) detection. The characterization confirmed that a nanocomposite hydrogel structure of TiO 2 /MXene-PVA/GO was formed. The as-prepared hydrogel substantially enhanced the sensor performances due to electrocatalytic activity of TiO 2 , high conductivity of MXene, and auto-sample preconcentration via PVA/GO hydrogel. The electrochemical behavior of NE was investigated by cyclic voltammetry and amperometry. Under optimized conditions, the TiO 2 /MXene-PVA/GO hydrogel/SPCE response due to the oxidation of NE at +0.4 V (vs. Ag|AgCl) is proportional to the concentration of NE over 0.01 to 1.00 μM (R 2  = 0.9968) and 1.00 to 60.0 μM (R 2  = 0.9936) ranges with a detection limit (3σ) of 6 nM without interferent effect from common interferences in urine. Furthermore, this sensor was employed for urinary NE determination and validated by high performance liquid chromatography (HPLC) with a UV detector at 280 nm; the average recovery was found to be 97.6 to 102%, with a relative standard deviation (RSD) less than 4.9%. This device was sensitive enough to evaluate an early stage of neurological disorder via detecting clinically relevant NE level. Eventually, it was integrated with pantyliners which could be a potential wearable sensor in the near future., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature.)

Developing eco-friendly and highly-efficient catalysts for the electrochemical nitrogen reduction reaction (NRR) under ambient conditions to replace the energy-intensive and environment-polluting Haber-Bosch process is of great significance, while remaining a long-standing challenge in the field of energy conversion today. Herein, through the first principles high-throughput screening, we systematically investigated the catalytic activity of a series of single metal atom immobilized on N-doped boron phosphide (N 3 -BP) for N 2 reduction, denoted as MN 3 -BP. In particular, a "four-step" screening strategy, involving the structural stability, N 2 chemisorption, low energy cost, as well as good selectivity, was adopted for the stringent screening of the promising MN 3 -BP candidates for NRR. Our results unveil that among these candidates, MoN 3 -BP eventually stands out, benefiting from its high selectivity and activity, as well as accompanying a considerably favorable limiting potential of -0.25 V for NRR. More impressively, the NRR activity origin of various candidates was revealed by the descriptor φ and ICOHP. Overall, our work not only accelerates the discovery of SACs for converting N 2 into sustainable NH 3 but also provides an exciting impetus for the rational design of NRR catalysts with high stability, high activity, and high selectivity.

Aqueous zinc-ion batteries (ZIBs) with cost-effective and safe features are highly competitive in grid energy storage applications, but plagued by the sluggish Zn 2+ diffusion kinetics and poor cyclability of cathodes. Herein, a one-stone-two-birds strategy of La 3+ incorporation (La-V 2 O 5 ) is developed to motivate Zn 2+ insertion/extraction kinetics and stabilize vanadium species for V 2 O 5 . Theoretical and experimental studies reveal the incorporated La 3+ ions in V 2 O 5 can not only serve as pillars to expand the interlayer distance (11.77 Å) and lower the Zn 2+ migration energy barrier (0.82 eV) but also offer intermediated level and narrower band gap (0.54 eV), thus accelerating the electron/ion diffusion kinetics. Importantly, the steadily doped La 3+ ions effectively stabilize the V-O bonds by shortening the bond length, thereby inhibiting vanadium species dissolution. Therefore, the resulting La-V 2 O 5 -ZIBs deliver an exceptional rate capacity of 405 mA h g -1 (0.1 A g -1 ), long-term stability with 93.8% retention after 5000 cycles (10 A g -1 ), and extraordinary energy density of 289.3 W h kg -1 , outperforming various metal-ions-doped V 2 O 5 cathodes. Moreover, the La-V 2 O 5 pouch cell presents excellent electrochemical performance and impressive flexibility and integration ability. The strategies of incorporating rare-earth-metal ions provide guidance to other well-established aqueous ZIBs cathodes and other advanced electrochemical devices.

Aqueous zinc-ion batteries (ZIBs) with exceptional safety and cost-effective features have captured researchers' attention, but the cathode materials available still need to be further explored. Herein, a flower-like W/WO 3 hybrid is developed as a cathode of ZIBs. Impressively, the W/WO 3 -ZIBs exhibit extraordinary rate performance (158 mA h g -1 under 0.1 A g -1 ) and remarkable cycling performance (96% over 1000 cycles). Additionally, an electrochemical mechanism based on reversible Zn 2+ insertion/extraction in W/WO 3 is firstly demonstrated, and the impressive flexibility and excellent capabilities of the soft-packaged batteries are also realized. Therefore, this research will pave a novel consideration of metal/metal oxide hybrids in designing cathodes of ZIBs with high electrochemical performance.

Biofilm formation on medical devices can induce complications. Graphene oxide/silver nanoparticles (GO/AgNPs) coated nickel-titanium (NiTi) alloy has been successfully produced. Therefore, the aim of this study was to determine the anti-bacterial and anti-biofilm effects of a GO/AgNPs coated NiTi alloy prepared by Electrophoretic deposition (EPD). GO/AgNPs were coated on NiTi alloy using various coating times. The surface characteristics of the coated NiTi alloy substrates were investigated and its anti-biofilm and anti-bacterial effect on Streptococcus mutans biofilm were determined by measuring the biofilm mass and the number of viable cells using a crystal violet assay and colony counting assay, respectively. The results showed that although the surface roughness increased in a coating time-dependent manner, there was no positive correlation between the surface roughness and the total biofilm mass. However, increased GO/AgNPs deposition produced by the increased coating time significantly reduced the number of viable bacteria in the biofilm (p < 0.05). Therefore, the GO/AgNPs on NiTi alloy have an antibacterial effect on the S. mutans biofilm. However, the increased surface roughness does not influence total biofilm mass formation (p = 0.993). Modifying the NiTi alloy surface using GO/AgNPs can be a promising coating to reduce the consequences of biofilm formation.

Graphene based materials (GBMs) have potentials for dental and medical applications. GBMs may cause changes in the levels of cytokine released in the body. This study aimed to study the corrosion resistance of graphene oxide (GO) and GO/silver (GO/Ag) nanocomposite coated nickel-titanium (NiTi) alloy by electrophoretic deposition and to access the viability of human pulp fibroblasts, and the interleukin (IL)-6 and IL-8 expression level. The bare and coated NiTi samples were characterized by scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS), Raman spectroscopy, surface profilometry, and X-ray diffraction (XRD). The corrosion resistance of the bare NiTi and coated NiTi samples were investigated by potentiodynamic polarization and electrochemical impedance spectroscopy in 3.5% NaCl solution. The cell viability of human pulp fibroblasts was accessed by the treated culture medium of the bare NiTi and coated NiTi alloys containing 1% fetal bovine serum. IL-6 and IL-8 expression levels were studied by human enzyme-linked immunosorbent assay (ELISA). Data were analyzed using One-way ANOVA (α  =  0.05). Both the GO-coated NiTi and GO/Ag-coated NiTi alloys showed better corrosion resistance, a lower rate of corrosion, and higher protection efficiency than the bare NiTi alloy. The coated NiTi alloys were biocompatible to human pulp fibroblasts and showed upregulation of IL-6 and IL-8 levels.

Background: Liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based assays are employed in more and more clinical laboratories to quantify steroids. The steroid quantification by LC-MS/MS shows great value in screening or diagnosing endocrine disorders; however, the number of functional steroids included in the LC-MS/MS methods is still limited., Methods: Here, we describe the performance and validation of a 20-steroid plasma panel by LC-MS/MS. The panel included progestogens (including mineralocorticoids and glucocorticoids), androgens and estrogens biosynthesized in steroid metabolic pathways. The LC-MS/MS method was validated according to guidance documents, and subsequently employed to profile steroid changes in endocrine disorders., Results: Using LC-MS/MS, 20 steroids were separated and quantified in 8 min. Coefficients of variation (CVs) of the 20 analytes at the lower limit of quantification (LLoQ) were all less than 15% (ranging from 1.84% to 14.96%). The linearity of the assay was demonstrated by all the R2 values greater than 0.995. Individual plasma steroids changed significantly in patients with subclinical Cushing's syndrome (SCS) and polycystic ovary syndrome (PCOS) - 17-hydroxypregnenolone (17-OH-PR), testosterone (T) and dihydrotestosterone (DHT) were significantly decreased in SCS patients, while in PCOS patients, pregnenolone, corticosterone (CORT), androstenedione (A4) and T were significantly increased and DHT was decreased., Conclusions: The LC-MS/MS method we developed for the quantification of 20 plasma steroids is clinical practicable. The steroid profiling data using this assay indicate its screening value for endocrine disorders. To further explore the value of the assay, more investigations are however needed.

A nanocomposite consisting of platinum particles, polyaniline and Ti 3 C 2 MXene (Pt/PANI/MXene) was used to modify a screen-printed carbon electrode (SPCE) to obtain sensors for hydrogen peroxide and lactate. This nanocomposite was characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM) and X-ray powder diffraction (XRD) to determine the physical morphologies and the nanocomposite elements. The modified electrode exhibited the improved current response towards hydrogen peroxide (H 2 O 2 ) compared with an unmodified electrode and provided a low detection limit of 1.0 μM. When lactate oxidase was immobilized on the modified electrode, the electrode responded to lactate via the H 2 O 2 generated in the enzymatic reaction. The lactate assay was performed by amperometry at a constant potential of +0.3 V (vs. Ag/AgCl). The linear range was found to be from 0.005 to 5.0 mM with a detection limit of 5.0 μM for lactate. Ultimately, this biosensor was used for the determination of lactate in milk samples with high stability and reliability. Graphical abstractSchematic representation of a novel platinum particles/polyaniline/MXene nanocomposite (Pt/PANI/MXene) for screen-printed carbon electrode (SPCE) modification to enhance the specific surface area for immobilization of lactate oxidase (LOx) and use as enzymatic biosensor for lactate determination in milk sample.

The Co were incorporated into the Ni-W/diamond nano-composite coatings by introducing CoSO₄ in the aforesaid plating bath. The effects of the Co content in the electrodeposit on microstructure and mechanical properties were analyzed. The morphology and the composition of the deposits were investigated by means of SEM and EDS, respectively. The Co content in the coatings increases progressively upon increasing the amount of CoSO₄ in the plating bath. The addition of small amount of CoSO₄ in the plating bath tends to enhance the hardness and wear performance of the Ni-W/diamond nano-composite coatings. While the amount of CoSO₄ beyond 0.2 g/L in the plating bath, the hardness and the wear resistance of the coatings decrease sharply.

The aim of this study was to evaluate the mechanical and tribological properties of graphene oxide/silver nanoparticle (GO/AgNP) coated medical grade nickel-titanium (NiTi) alloy. The alloy substrates were coated using electrophoretic deposition at 30 V for 1, 5, and 10 min and were characterized by SEM, Raman spectroscopy, EDS, and surface profilometer. Mechanical and tribological tests were performed for hardness, Young's modulus, and friction coefficient. The data were analyzed using the Kruskal-Wallis test at a significance level of 0.05 to compare the coatings' roughness, thickness, friction coefficient, and hardness at the different coating times. The GO/AgNP coatings were confirmed with Raman spectroscopy, which demonstrated the presence of D bands and G bands at ∼1300 cm -1 and ∼1600 cm -1 . The intensity ratios of the D and G bands ( I D / I G ) were 0.838, 0.836, and 0.837 in the 1, 5, and 10 min coated groups, respectively. The coating thickness ranged from 0.46-1.34 μ m and the mean surface roughness (Ra) ranged from 50.72-69.93 nm. Increasing the coating time from 1-10 min increased the roughness, thickness, and Young's modulus of surface coating. The friction coefficients of the coated NiTi alloy were significantly lower compared with that of the uncoated NiTi allloy ( p < 0.001). The GO/AgNP nanocomposite coated NiTi alloy demonstrated improved mechanical strength and a reduced friction coefficient that would be more favorable for biomedical applications.

Charge engineering of carbon materials with many defects shows great potential in electrocatalysis, and molybdenum carbide (Mo 2 C) is one of the noble-metal-free electrocatalysts with the most potential. Herein, we study the Mo 2 C on pyridinic nitrogen-doped defective carbon sheets (MoNCs) as catalysts for the hydrogen evolution reaction. Theoretical calculations imply that the introduction of Mo 2 C produces a graphene wave structure, which in some senses behaves like N doping to form localized charges. Being an active electrocatalyst, MoNCs demonstrate a Tafel slope as low as 60.6 mV dec -1 and high durability of up to 10 h in acidic media. Besides charge engineering, plentiful defects and hierarchical morphology also contribute to good performance. This work underlines the importance of charge engineering to boost catalytic performance.

The detection of water soluble vitamins using electrochemical method is widely established in pharmaceutical quality control laboratories, and especially the recent advances in hybrid heterostrucure nanomaterials has devoted to enhance the significant analytical parameters like sensitivity, selectivity and fast response time. Herein, we report the synthesis of a hybrid heterostructure comprising SnO 2 nanoparticles supported mesoporous TiO 2 , and the obtained nanocomposite were fabricated over glassy carbon electrode (GCE) for the electrochemical oxidation of vitamin B 6 in pharmaceutical tablets. The designed SnO 2 -TiO 2 /GC modified electrode exhibits well-defined oxidation peak with lowering over-potential and larger signal response compared to the pristine counterparts, and it is mainly due to the formation of abundant active surface layer offered by SnO 2 cocatalyst, and thus significantly enhances the electrochemical surface area. Differential pulse voltammetry (DPV) measurements revealed a sharp increase in the anodic peak current upon addition of increasing concentration of vitamin B 6 . The analytical performance of the modified electrode displayed a wide linear range (0.1-31.4 µM), high selectivity, and excellent sensitivity (759.73 µA mM -1  cm -2 ) with low detection limit (35 nM). Thus, the resultant mesoporous hybrid nanocatalyst provides an efficient electrochemical platform for determination of various potential analytes., (Copyright © 2019 Elsevier Inc. All rights reserved.)

The construction of a 2D-2D heterostructured composite is an efficient method to improve the photocatalytic hydrogen generation capability under visible light. In this work, simple heat treatment of a mixture of g-C 3 N 4 and delaminated Ti 3 C 2 was used to prepare a series of d-Ti 3 C 2 /TiO 2 /g-C 3 N 4 nanocomposites. The d-Ti 3 C 2 not only acted as the support layer and resource to glue the anatase TiO 2 particles and g-C 3 N 4 layers together but also served as the fast electron transfer channel to improve the photogenerated charge carriers' separation efficiency. By tuning the g-C 3 N 4 /d-Ti 3 C 2 mass ratio, heating temperature and soaking time, the d-Ti 3 C 2 /TiO 2 /g-C 3 N 4 nanocomposite 4-1-350-1 achieved an excellent H 2 evolution rate of 1.62 mmol h -1  g -1 driven by a 300 W Xe lamp with a 420 nm cutoff filter. The heterostructured composite photocatalyst was stable even after 3 cycles, representing excellent potential for the practical application in solar energy conversion., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Semiconductor photocatalysis is regarded as an ideal method for use in solving the energy shortage and environmental issues by converting solar energy to chemical energy. Herein, we have designed a facile synthetic methodology to obtain a ternary co-modified g-C 3 N 4 composite via WS 2 and carbon-doped TiO 2 (C-TiO 2 ) nanorods with highly efficient photocatalytic activity for hydrogen production from deionized (DI) water and a natural seawater system under visible-light illumination. This composite exhibits enhanced photocatalytic activity compared to the pristine g-C 3 N 4 , WS 2 , C-TiO 2 nanorods, and the reference-modified g-C 3 N 4 composite with individual WS 2 or C-TiO 2 nanorods. Co-modified g-C 3 N 4 composite shows a great photostability in both DI water and seawater. Under λ=420 nm monochromatic light illumination, the apparent quantum efficiency of the co-modified g-C 3 N 4 composite in seawater solution is 13.08 %, which is higher than pure g-C 3 N 4 (5.06 %). WS 2 , TiO 2 , and g-C 3 N 4 constitute a ternary heterojunction boosting the fast separation of photoinduced electron-hole pairs, which plays a crucial role in enhancing photocatalytic activity. Therefore, the WS 2 and C-TiO 2 nanorod co-modified g-C 3 N 4 composite with high photocatalytic performance provides a promising candidate for rationally utilizing the seawater resource to produce clean chemical energy., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Rational design and synthesis of a new silicon carbide/titanium carbide@silicon oxide/titanium dioxide (SiC/TiC@SiO x /TiO 2 ) porous core-shell nanostructured material could significantly enhance the specific capacity, rate capability, and cycle stability of electrodes. The results demonstrate that the specific capacities are 387, 300, 252, 210, 174 and 151 mA h g -1 at 100, 200, 500, 1000, 1500 and 2000 mA g -1 , respectively. The newly designed electrode still exhibits a larger specific capacity of 217 mA h g -1 at 1000 mA g -1 after the 1000th cycle.

Hydrogen can be the potential substitute energy carrier for fuel while electrolysis water with hydrogen evolution reaction (HER) is an efficient way to produce hydrogen. Highly active and robust electrocatalysts composed by earth abundant elements are required. Herein, nickel-copper-phosphorus (Ni-Cu-P) electrocatalysts are designed and synthesized by a facile one-step electrodeposition method. A unique pine-needle-like dendrite nanotube morphology of Ni-Cu-P electrocatalyst can be synthesized when copper content changed and impressive HER activity obtained in alkaline and acidic media. Briefly, the overpotential reaches 120 mV in 1 M KOH and 150 mV in 0.5 M H 2 SO 4 at the current density of 10 mA cm -2 , with the corresponding Tafel slope reaching 69 mV dec -1 . The results are close to that of commercial Pt/C catalysts (37 mV in 1 M KOH). Furthermore, the density functional theory calculations also demonstrate that P-incorporated Ni-Cu, Cu-incorporated Ni-P, and Ni-incorporated Cu-P have the optimized hydrogen adsorption free energy (Δ G H* ) of -0.066, -0.157, and -0.003 eV, respectively, which are more suitable than those of Ni-Cu, Ni-P, and Cu-P, respectively. The Ni-incorporated Cu-P even has a much smaller Δ G H* of -0.003 than that of Pt (∼-0.09 eV). We believe that our study will provide a new strategy to design non-noble metal alloy materials for practical applications in catalysis and energy fields.

The use of polymeric materials (PMs) and polymeric films (PMFs) has increased in medicine and dentistry. This increasing interest is attributed to not only the excellent surfaces of PMs and PMFs but also their desired mechanical and biological properties, low production cost, and ease in processing, allowing them to be tailored for a wide range of applications. Specifically, PMs and PMFs are used in dentistry for their antimicrobial, drug delivery properties; in preventive, restorative and regenerative therapies; and for corrosion and friction reduction. PMFs such as acrylic acid copolymers are used as a dental adhesive; polylactic acids are used for dental pulp and dentin regeneration, and bioactive polymers are used as advanced drug delivery systems. The objective of this article was to review the literatures on the latest advancements in the use of PMs and PMFs in medicine and dentistry. Published literature (1990-2017) on PMs and PMFs for use in medicine and dentistry was reviewed using MEDLINE/PubMed and ScienceDirect resources. Furthermore, this review also explores the diversity of latest PMs and PMFs that have been utilized in dental applications, and analyzes the benefits and limitations of PMs and PMFs. Most of the PMs and PMFs have shown to improve the biomechanical properties of dental materials, but in future, more clinical studies are needed to create better treatment guidelines for patients.

In this paper, an efficient method to produce a ZnO/BiOI nano-heterojunction is developed by a facile solution method followed by calcination. By tuning the ratio of Zn/Bi, the morphology varies from nanoplates, flowers to nanoparticles. The heterojunction formed between ZnO and BiOI decreases the recombination rate of photogenerated carriers and enhances the photocatalytic activity of ZnO/BiOI composites. The obtained ZnO/BiOI heterostructured nanocomposites exhibit a significant improvement in the photodegradation of rhodamine B under visible light (λ ≥ 420 nm) irradiation as compared to single-phase ZnO and BiOI. A sample with a Zn/Bi ratio of 3:1 showed the highest photocatalytic activity (≈99.3% after 100 min irradiation). The photodegradation tests indicated that the ZnO/BiOI heterostructured nanocomposites not only exhibit remarkably enhanced and sustainable photocatalytic activity, but also show good recyclability. The excellent photocatalytic activity could be attributed to the high separation efficiency of the photoinduced electron-hole pairs as well as the high specific area.

Nickel-tungsten (Ni–W) coatings were fabricated by electrodeposition method with varying quantities of sodium dodecyl sulphate and sodium bromide to examine the effects of the aforesaid additives on the coatings. The obtained nanocoatings were studied by X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, and hardness tester. The hardness, tungsten content and grain size attained a maximum value at current density of 0.15 A/cm²,0.1 A/cm² and 0.1 A/cm², respectively. There was a pronounced impact of both the additives on the microstructure and morphology of the coatings. According to results, there are considerable difference in terms of the impact caused by the additives to the tungsten content, hardness and grain size of the coatings. The obtained results suggest that hardness of coatings is mainly contributed by W content in the deposits.

In this study, pure ZnO, CeO2 and ZnO/CeO2 nanocomposites were synthesized using a thermal decomposition method and subsequently characterized using different standard techniques. High-resolution X-ray photoelectron spectroscopy measurements confirmed the oxidation states and presence of Zn(2+), Ce(4+), Ce(3+) and different bonded oxygen species in the nanocomposites. The prepared pure ZnO and CeO2 as well as the ZnO/CeO2 nanocomposites with various proportions of ZnO and CeO2 were tested for photocatalytic degradation of methyl orange, methylene blue and phenol under visible-light irradiation. The optimized and highly efficient ZnO/CeO2 (90:10) nanocomposite exhibited enhanced photocatalytic degradation performance for the degradation of methyl orange, methylene blue, and phenol as well as industrial textile effluent compared to ZnO, CeO2 and the other investigated nanocomposites. Moreover, the recycling results demonstrate that the ZnO/CeO2 (90:10) nanocomposite exhibited good stability and long-term durability. Furthermore, the prepared ZnO/CeO2 nanocomposites were used for the electrochemical detection of uric acid and ascorbic acid. The ZnO/CeO2 (90:10) nanocomposite also demonstrated the best detection, sensitivity and performance among the investigated materials in this application. These findings suggest that the synthesized ZnO/CeO2 (90:10) nanocomposite could be effectively used in various applications.

Electroplated hard chrome coating is widely used as a wear resistant coating to prolong the life of mechanical components. However, the electroplating process generates hexavalent chromium ion which is known carcinogen. Hence, there is a major effort throughout the electroplating industry to replace hard chrome coating. Composite coating has been identified as suitable materials for replacement of hard chrome coating, while deposition coating prepared using traditional co-deposition techniques have relatively low particles content, but the content of particles incorporated into a coating may fundamentally affect its properties. In the present work, Ni-W/diamond composite coatings were prepared by sediment co-electrodeposition from Ni-W plating bath, containing suspended diamond particles. This study indicates that higher diamond contents could be successfully co-deposited and uniformly distributed in the Ni-W alloy matrix. The maximum hardness of Ni-W/diamond composite coatings is found to be 2249 ± 23 Hv due to the highest diamond content of 64 wt.%. The hardness could be further enhanced up to 2647 ± 25 Hv with heat treatment at 873 K for 1 h in Ar gas, which is comparable to hard chrome coatings. Moreover, the addition of diamond particles could significantly enhance the wear resistance of the coatings.

Cubic (space group: Fmm) iridium phosphide, Ir2P, has been synthesized at high pressure and high temperature. Angle-dispersive synchrotron X-ray diffraction measurements on Ir2P powder using a diamond-anvil cell at room temperature and high pressures (up to 40.6 GPa) yielded a bulk modulus of B0 = 306(6) GPa and its pressure derivative B0' = 6.4(5). Such a high bulk modulus attributed to the short and strongly covalent Ir-P bonds as revealed by first - principles calculations and three-dimensionally distributed [IrP4] tetrahedron network. Indentation testing on a well-sintered polycrystalline sample yielded the hardness of 11.8(4) GPa. Relatively low shear modulus of ~64 GPa from theoretical calculations suggests a complicated overall bonding in Ir2P with metallic, ionic, and covalent characteristics. In addition, a spin glass behavior is indicated by magnetic susceptibility measurements.

We report on the prediction of the zinc-blende structure BP into a novel C2/m phase from 113 to 208 GPa which possesses zigzag phosphorus chain structure, followed by another P42/mnm structure above 208 GPa above using the particle-swarm search method. Strong electron-phonon coupling λ in compressed BP is found, in particular for C2/m phase with the zigzag phosphorus chain, which has the highest λ (0.56-0.61) value among them, leading to its high superconducting critical temperature Tc (9.4 K-11.5 K), which is comparable with the 4.5 K to 13 K value of black phosphorus phase I (orthorhombic, Cmca). This is the first system in the boron phosphides which shows superconductivity from the present theoretical calculations. Our results show that pressure-induced zigzag phosphorus chain in BP exhibit higher superconducting temperature TC, opening a new route to search and design new superconductor materials with zigzag phosphorus chains.

ZnO, aside from TiO2, has been considered as a promising material for purification and disinfection of water and air, and remediation of hazardous waste, owing to its high activity, environment-friendly feature and lower cost. However, their poor visible light utilization greatly limited their practical applications. Herein, we demonstrate the fabrication of different aspect ratios of the ZnO nanorods with surface defects by mechanical-assisted thermal decomposition method. The experiments revealed that ZnO nanorods with higher aspect ratio and surface defects show significantly higher photocatalytic performances.

Using the first-principles calypso algorithm for crystal structure prediction, we have predicted two orthorhombic Cmcm and Amm2 structures of ZrB4, which are energetically much superior to the previously proposed WB4-, CrB4-, and MoB4-type structures and stable against decompression into a mixture of Zr and B at ambient pressure. The two orthorhombic structures consist of a hexagonal B ring and ZrB12 units connected by edges and one hexagonal B ring in Cmcm and Amm2 structure, respectively. The calculated large shear modulus (e.g., 229 GPa) and high hardness (42.8 GPa for Cmcm and 42.6 GPa for Amm2) reveal that they are potentially superhard materials. The high hardness is attributed to a stacking of B-Zr-B "sandwiches" layers linked by strong covalent B-B bonding.

A sapphire anvil cell, a portable system having a sample volume of about 400 mm(3) (Phi8x8 mm), has been developed for gas hydrates research under high pressure. As both pressure and temperature of the sample can be precisely monitored in real time, the system has significant advantages for gas hydrates research at the pressure range of 1-40 MPa and temperature range of 250-350 K. We have applied this sapphire anvil cell system to carry out experiments for investigating the formation and dissociation of CO(2) hydrate. In addition, the developed sapphire anvil cell can be used for in situ thermal, electric, ultrasonic, visible light, Raman, and IR measurements.