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At least 1,531 records · Page 85

In-situ Investigations on Gold Nanoparticles Stabilization Mechanisms in Biological Environments Containing HSA

Nanoparticles (NPs) developments advance innovative biomedical applications. However, complex interactions and the low colloidal stability of NPs in biological media restrict their widespread utilization. The influence of NPs properties on the colloidal stability for gold NPs with 5 and 40 nm in diameter with two surface modifications, methoxy-polyethylene glycol-sulfhydryl (PEG) and citrate, in NaCl and human serum albumin (HSA) protein solution, is investigated. This study is based on small-angle X-ray scattering (SAXS) methods allowing the in-situ monitoring of interactions in physiological conditions. The PEG coating provides high colloidal stability for NPs of both sizes. For 5 nm NPs in NaCl solution, a stable 3D self-assembled body-centered cubic (BCC) arrangement is detected with an interparticle distance of 20.7 ± 0.1 nm. In protein solution, this distance increases to 21.9 ± 0.1 nm by protein penetration inside the ordered structure. For citrate-capped NPs, a different mechanism is observed. The protein particles attach to the NPs surfaces, and an appropriate concentration of proteins results in a stable suspension. Cryogenic transmission electron microscopy (Cryo-TEM), UV–visible spectroscopy, and dynamic light scattering (DLS) support the SAXS results. The findings will pave the way to design and synthesize NPs with controlled behaviors in biomedical applications.

36 MATERIALS SCIENCE↗

Electron Redistributed S-Doped Nickel Iron Phosphides Derived from One-Step Phosphatization of MOFs for Significantly Boosting Electrochemical Water Splitting

Nonprecious transition metal-organic frameworks (MOFs) are one of the most promising precursors for developing electrocatalysts with high porosity and structural rigidity. This study reports the synthesis of high efficiency electrocatalysts based on S-doped NiFeP. MOF-derived S-doped NiFeP structure is synthesized by a one-step phosphorization process with using S-doped MOFs as the precursor, which is more convenient and environment friendly, and also helps retain the samples’ framework. The oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) performance of the NiFeP catalysts can be improved after partially replacing P by S due to the tunable electronic structure. The optimized CCS-NiFeP-10 reaches a current density of 10 mA cm –2 for OER with an overpotential of 201 mV and outperforms most NiFe-based catalysts. The S doping plays an important role in tuning the ΔG values for intermediates formation in Ni atoms to a suitable value and exhibits a pronouncedly improved the OER performance. CCS-NiFeP-20 sample presents excellent HER performance due to the d-band center downshifting from the Fermi level. When the voltage of the electrolytic cell is 1.50 V, a current density of 10 mA cm –2 can be obtained. This strategy paves the way for designing highly active none-noble metal catalysts.

36 MATERIALS SCIENCE↗

Atomically Precise Single Metal Oxide Cluster Catalyst with Oxygen–Controlled Activity

Single cluster catalysts (SCCs) consisting of atomically precise metal nanoclusters dispersed on supports represent a new frontier of heterogeneous catalysis. However, the ability to synthesize SCCs with high loading and to precisely introduce non-metal atoms to further tune their catalytic activity and reaction scope of SCCs have been longstanding challenges. In this work, a new interface confinement strategy is developed for the synthesis of a high density of atomically precise Ru oxide nanoclusters (Ru 3 O 2 ) on reduced graphene oxide (rGO), attributed to the suppression of diffusion-induced metal cluster aggregation. Ru 3 O 2 /rGO exhibits a significantly enhanced activity for oxidative dehydrogenation of 1,2,3,4-tetrahydroquinoline (THQ) to quinoline with a high yield (≈86%) and selectivity (≈99%), superior to Ru and RuO 2 nanoparticles, and homogeneous single/multiple-site Ru catalysts. In addition, Ru 3 O 2 /rGO is also capable of efficiently catalyzing more complex oxidative reactions involving three reactants. The theoretical calculations reveal that the presence of two oxygen atoms in the Ru 3 O 2 motif not only leads to a weak hydrogen bonding interaction between the THQ reactant and the active site, but also dramatically depletes the density of states near the Fermi level, which is attributed to the increased positive valence state of Ru and the enhanced oxidative activity of the Ru 3 O 2 cluster for hydrogen abstraction.

36 MATERIALS SCIENCE↗

Effect of the Selective Halogenation of Small Molecule Acceptors on the Blend Morphology and Voltage Loss of High-Performance Solar Cells

Herein, the impacts of the selective halogenation at two different positions of dicyanomethylene-3-indanone (IC) end groups and inner side chains of small molecular acceptors (SMAs) on the P D :SMA interfacial interactions, blend morphology, and resulting photovoltaic properties are described. In this study, four different SMAs (A1, A2, A3, and A4) with the same molecular backbone, but with different degrees of halogenation, are synthesized. The IC end groups on the backbones of the A1 and A3, and A2 and A4 SMAs are chlorinated and fluorinated, respectively; in addition, 6-phenoxyhexyl inner side chains of the A3 and A4 are chlorinated. The SMAs are paired with a chlorinated PBDT-Cl PD to construct organic solar cells (OSCs). The PBDT-Cl:A4-based OSC exhibits the highest power conversion efficiency of 17.2%, outperforming the PBDT-Cl:A1-(13.3%), PBDT-Cl:A2-(15.6%), and PBDT-Cl:A3-based OSC (16.5%). The Cl atoms on the side chains in the A3 and A4 SMAs enhance the molecular/energetic interactions at the P D :SMA interfaces and improve the blend morphology in terms of domain purity and spacing. These effects lead to the improved fill factors and reduced voltage loss of the PBDT-Cl:A3- and PBDT-Cl:A4-based OSCs. This study demonstrates the importance of appropriate halogenation of SMAs in optimizing the blend morphology, reducing voltage loss, and improving OSC performance.

36 MATERIALS SCIENCE↗

Unravelling the Role of Electron Acceptors for the Universal Enhancement of Charge Transport in Quinoid-Donor-Acceptor Polymers for High-Performance Transistors

The quinoid-donor-acceptor (Q-D-A) strategy has recently emerged as a promising approach for constructing high mobility semiconducting polymers. In order to fully explore the potential of this strategy in improving the charge transport and elucidating the structure-property-performance relationships in Q-D-A polymers, a series of new polymers with different electron acceptor units and backbone coplanarity have been synthesized and characterized. In this work, all of the resulting Q-D-A polymers exhibit much more planar backbone conformations in comparison to their donor-acceptor (D-A) counterparts. Moreover, organic field-effect transistors based on Q-D-A polymers exhibit excellent effective hole mobilities in a range of 0.44 to 3.35 cm 2 V –1 s –1 , most of which are orders of magnitude higher than those of their corresponding D-A polymers. Notably, the hole mobility of 3.35 cm 2 V –1 s –1 is among the highest for the quinoidal-aromatic polymers characterized by conventional spin-coating methods. Furthermore, the role of electron acceptors in Q-D-A polymers has been comprehensively investigated. Polymers with stronger acceptor units are more inclined to deliver edge-on lamellas, high film crystallinity, small effective hole masses, and decent operational stability. The detailed structure-property-device performance relationship will pave the way toward high performance semiconducting polymers using the potent Q-D-A strategy.

36 MATERIALS SCIENCE↗

Benzimidazole Based Hole‐Transporting Materials for High‐performance Inverted Perovskite Solar Cells

Abstract Interfaces play a decisive role in perovskite solar cells’ power conversion efficiency and their long‐term durability. Small‐molecule hole‐transporting materials (HTMs) have grabbed enormous attention due to their structural flexibility, material properties, and stabilities, allowing for improved operational durability in perovskite photovoltaics. This study synthesizes and investigates a new class of benzimidazole‐based small molecules, named YJS001 and YJS003 , serving as the HTMs to enable high‐efficiency mixed‐cation mixed‐halide perovskite solar cells. The benzimidazole‐based materials are dopant‐free HTMs composed of donor and acceptor building blocks that are designed to engineer the energy level alignment near the HTM/perovskite interface. Mixed‐cation mixed‐halide perovskites can be grown uniformly on both HTMs with large crystalline grains. It is discovered that the donor‐rich YJS003 ‐based solar cell exhibits a high open‐circuit voltage of 1.09 V with a champion power conversion efficiency of over 20%. Power‐dependent current–voltage characteristics of the solar cells are analyzed, from which the high performance of YJS003's excellent hole mobility and well‐aligned energy level is attributed. This work introduces a new class of benzimidazole‐based small molecules as HTMs, that paves the path for dopant free interface material development for commercialization of perovskite solar cells.

14 SOLAR ENERGY↗

Impacts of Bond Type and Grafting Density on the Thermal, Structural, and Transport Behaviors of Nanoparticle Organic Hybrid Materials–Based Electrolytes

Nanoscale Organic Hybrid Materials (NOHMs) consist of polymers tethered to a nanoparticle surface, and NOHMs formed with an ionic bond between the polymer and nanoparticle have been proposed for electrochemical applications. NOHMs exhibit negligible vapor pressure, chemical tunability, oxidative thermal stability, and high ionic conductivity making them attractive in reactive and separation systems. In this study, NOHMs are synthesized by tethering Jeffamine M2070 (HPE) to SiO 2 nanocores via ionic (NOHM-I-HPE) and covalent (NOHM-C-HPE) bonding to investigate the effect of the bond type on the thermal, structural and transport properties of the tethered HPE. In the neat state, NOHM-C-HPE displays the highest thermal stability in a nitrogen atmosphere, while NOHM-I-HPE is the most stable under oxidative conditions. Small-angle neutron scattering (SANS) reveals the presence of multiple types of HPE polymers in aqueous solutions of NOHM-I-HPE (i.e., tethered, interacting, and free), whereas only tethered HPE is observed in NOHM-C-HPE systems. Moreover, the SANS profiles identify clustering of NOHM-C-HPE in aqueous solutions, but not in the corresponding NOHM-I-HPE solutions, suggesting that the free HPE chains stabilize the dispersion of NOHM-I-HPE. Furthermore, the results of this study elucidate how the bond type and grafting density can be used to tune the properties of NOHMs.

25 ENERGY STORAGE↗

Unprecedented Multifunctionality in 1D Nb 1- x Ta x S 3 Transition Metal Trichalcogenide Alloy

One-dimensional (1D) van der Waals materials, such as nanofibers or nanoribbons are considered as the future ultimate limit of downscaling for modern electrical and electrochemical devices. Here, for the first time, we successfully synthesize nanofibers of a solid solution transition metal trichalcogenide (TMTC), Nb 1-x Ta x S 3 , with outstanding electrical, thermal, and electrochemical characteristics rivaling the performance of the-state-of-the art materials for each application. This material shows nearly unchanged sheet resistance (≈740 Ω/sq -1 ) versus bending cycles tested up to 90 cycles, stable sheet resistance in ambient conditions tested up to 60 days, remarkably high electrical breakdown current density of ≈ 30 MA cm -2 , strong evidence of successive charge density wave (CDW) transitions, and outstanding thermal stability up to ≈900 K. Additionally, this material demonstrates excellent activity and selectivity for CO2 conversion to CO reaching ≈ 350 mA cm -2 at – 0.8 V vs RHE with an outstanding turnover frequency number of 25 for CO formation. It also exhibits an excellent performance in a high-rate Li-air battery with the specific capacity of 3000 mAhg -1 at a high current density of 0.3 mAcm -2 . This study uncovers the multifunctionality in 1D TMTC alloys for a wide range of high-impact applications and opens a new direction for the design of the next generation of low-dimensional materials with high performance.

36 MATERIALS SCIENCE↗

Ultra-Stretchable, Ionic Conducting, Pressure-Sensitive Adhesive with Dual Role for Stable Li-Metal Batteries

The practical application of lithium (Li) metal battery is impeded by the Li dendrite growth and unstable solid electrolyte interphase (SEI) layer. Herein, an ultra-stretchable and ionic conducting chemically crosslinked pressure-sensitive adhesive (cPSA) synthesized via the copolymerization of 2-ethylhexyl acrylate and acrylic acid with poly(ethyleneglycol)dimethacrylate as crosslinker (short for 70cPSA), is developed as both artificial SEI layer and solid polymer electrolyte (SPE) for stable Li-metal electrode, enabling all-solid-state Li metal batteries with excellent cycling performance. As an artificial SEI layer, the 70cPSA-modified electrodes exhibit excellent electrochemical performance in Li|70cPSA@Cu half cells and 70cPSA@Li|70cPSA@Li symmetric cells. In full cells with LiFePO 4 (LFP) as cathode, the 70cPSA@Li|LFP cell exhibits stable cycling performance over 250 cycles. Utilized as SPE, the all-solid-state Li|SPE|LFP cell delivers excellent cycling stability with a capacity retention of 86% over 500 cycles. With high-voltage LiNi 0.8 Mn 0.1 Co 0.1 O 2 (NMC811) as cathode, the Li|SPE|NMC811 cell exhibits a discharge capacity of 124.3 mAh g -1 with a capacity retention of 71% after 200 cycles. Furthermore, the rational design of PSAs and investigation of their dual role for stable and safe Li-metal batteries may shed a light on adhesive polymers for battery applications.

25 ENERGY STORAGE↗

High‐Throughput Screening Assisted Discovery of a Stable Layered Anti‐Ferromagnetic Semiconductor: CdFeP 2 Se 6

Recent advances in 2D magnetism have heightened interest in layered magnetic materials due to their potential for spintronics. In particular, layered semiconducting antiferromagnets exhibit intriguing low-dimensional semiconducting behavior with both charge and spin as carrier controls. However, synthesis of these compounds is challenging and remains rare. Here, first-principles based high-throughput search is conducted to screen potentially stable mixed metal phosphorous trichalcogenides (MM ' P 2 X 6 , where M and M ' are transition metals and X is a chalcogenide) that have a wide range of tunable bandgaps and interesting magnetic properties. Among the potential candidates, a stable semiconducting layered magnetic material, CdFeP 2 Se 6 , that exhibits a short-range antiferromagnetic order at T N = 21 K with an indirect bandgap of 2.23 eV is successfully synthesized . This work suggests that high-throughput screening assisted synthesis can be an effective method for layered magnetic materials discovery.

2D materials↗

An Extremely Stable, Highly Soluble Monosubstituted Anthraquinone for Aqueous Redox Flow Batteries

An extremely stable, energy-dense (53.6 Ah L –1 , 2 M transferrable electrons), low crossover (permeability of <1 × 10 –13 cm 2 s –1 using Nafion 212 (Nafion is a trademark polymer from DuPont)), and potentially inexpensive anthraquinone with 2-2-propionate ether anthraquinone structure (abbreviated 2-2PEAQ) is synthesized and extensively evaluated under practically relevant conditions for use in the negolyte of an aqueous redox flow battery. 2-2PEAQ shows a high stability with a fade rate of 0.03–0.05% per day at different applied current densities, cut-off voltage windows, and concentrations (0.1 and 1.0 M ) in both a full cell paired with a ferro/ferricyanide posolyte as well as a symmetric cell. 2-2PEAQ is further shown to have extreme long-term stability, losing only ≈0.01% per day when an electrochemical rejuvenation strategy is employed. From post-mortem analysis (nuclear magnetic resonance (NMR), liquid chromatography–mass spectrometry (LC-MS), and cyclic voltammetry (CV)) two degradation mechanisms are deduced: side chain loss and anthrone formation. 2-2PEAQ with the ether linkages attached on carbons non-adjacent to the central ring is found to have three times lower fade rate compared to its isomer with ether linkages on the carbon adjacent to the central quinone ring. Here, the present study introduces a viable negolyte candidate for grid-scale aqueous organic redox flow batteries.

25 ENERGY STORAGE↗

Smartly Optimizing Crystallinity, Compatibility, and Morphology for Polymer Solar Cells by Small Molecule Acceptor with Unique 2D-EDOT Side Chain

A desired morphology is essential for achieving efficient polymer solar cells. Donors and acceptors with appropriate crystallization can lead to a suitable phase-separated morphology for effective photocurrent generation process. Inspired by the success of Y6 acceptors and the 2D side chain engineering on popular polymer donors and small molecule acceptors, the usage of unique 2D 3,4-ethylene dioxythiophene (EDOT) side chains on Y6 to regulate its crystallinity, compatibility, and thus the related blend morphology is explored. Here, in this study, two molecules of BTP-EDOT-4F and BTP-EDOT-4Cl with such unique 2D EDOT side chains are designed and synthesized. Due to the advantage of EDOT side chain, when these molecules are blended with PM6, the decent power conversion efficiencies (PCEs) of 16.78% and 15.87% are obtained. Furthermore, BTP-EDOT-4F is selected as the third component and added into PM6:L8-BO binary system to form ternary blends. The optimized crystallinity, compatibility, and morphology of such ternary blend are discovered in the presence of BTP-EDOT-4F, which enables efficient exciton dissociation and charge transport as well as decreased recombination, resulting in higher short circuit current density (J sc ) and fill factor. Finally, the outstanding PCE of 18.56% is achieved in ternary blends containing PM6, L8-BO, and BTP-EDOT-4F.

2D EDOT side chains↗

Tuning the Intermolecular Electrostatic Interaction toward High-Efficiency and Low-Cost Organic Solar Cells

Organic solar cells (OSCs) have achieved much progress with rapidly increasing power conversion efficiencies (PCEs). It should be noted that the top-performance OSCs are generally consisted of active materials with complex chemical structures, resulting in high costs. Here, combining the material design and morphology control, high-efficiency OSCs are fabricated by a low-cost donor: acceptor blend. A completely non-fused electron acceptor named Tz is designed and synthesized via introducing thiazole units on both sides of a bithiophene core, which shows an outstanding PCE of 13.3% with a typical polythiophene donor. More importantly, optimization guidelines are presented to get excellent morphology for low-cost donor:acceptor systems. Three polythiophenes are selected, poly(3-hexylthiophene) and its two derivatives with electron-withdrawing substitutions (PDCBT and PDCBT-2F), as donors to fabricate the cell devices. The computational and experimental data reveal that decreasing the electrostatic interaction between polythiophene and Tz is the key to getting a suppressed miscibility and thus a high phase purity. Finally, this study provides insight into the molecular design and donor:acceptor matching requirements for high-efficiency and low-cost OSCs.

14 SOLAR ENERGY↗

Fe-N 4 O-C Nanoplates Covalently Bonding on Graphene for Efficient CO 2 Electroreduction and Zn-CO 2 Batteries

Electrochemical carbon dioxide (CO 2 ) reduction into value-added products holds great promise in moving toward carbon neutrality but remains a grand challenge due to lack of efficient electrocatalysts. Herein, the nucleophilic substitution reaction is elaborately harnessed to synthesize carbon nanoplates with a Fe-N 4 O configuration anchored onto graphene substrate (Fe-N 4 O-C/Gr) through covalent linkages. Density functional theory calculations demonstrate the unique configuration of Fe-N 4 O with one oxygen (O) atom in the axial direction not only suppresses the competing hydrogen evolution reaction, but also facilitates the desorption of *CO intermediate compared with the commonly planar single-atomic Fe sites. The Fe-N 4 O-C/Gr shows excellent performance in the electroreduction of CO 2 into carbon monoxide (CO) with an impressive Faradaic efficiency of 98.3% at -0.7 V versus reversible hydrogen electrode (RHE) and a high turnover frequency of 3511 h -1 . Furthermore, as a cathode catalyst in an aqueous zinc (Zn)-CO 2 battery, the Fe-N 4 O-C/Gr achieves a high CO Faradaic efficiency (≈91%) at a discharge current density of 3 mA cm -2 and long-term stability over 74 h. Here this work opens up a new route to simultaneously modulate the geometric and electronic structure of single-atomic catalysts toward efficient CO 2 conversion.

25 ENERGY STORAGE↗

Flexible Vanadium Dioxide Photodetectors for Visible to Longwave Infrared Detection at Room Temperature

Abstract Flexible optoelectronics is a rapidly growing field, with a wide range of potential applications. From wearable sensors to bendable solar cells, curved displays, and curved focal plane arrays, the possibilities are endless. The criticality of flexible photodetectors for many of these applications is acknowledged, however, devices that are demonstrated thus far are limited in their spectral range. In this study, flexible photodetectors are demonstrated using a VO x nanoparticle ink, with an extremely broad operating wavelength range of 0.4 to 20 µm. This ink is synthesized using a simple and scalable wet‐chemical process. These photodetectors operate at room temperature and exhibit minimal variance in performance even when bent at angles of up to 100 ° at a bend radius of 6.4 mm. In addition, rigorous strain testing of 100 bend and release cycles revealed a photoresponse with a standard deviation of only 0.55%. This combination of mechanical flexibility, wide spectral response, and ease of fabrication makes these devices highly desirable for a wide range of applications, including low‐cost wearable sensors and hyperspectral imaging systems.

36 MATERIALS SCIENCE↗

On the Interplay between Size and Disorder in Suppressing Intercalation-Induced Phase Transitions in Pseudocapacitive Nanostructured MoS 2

Pseudocapacitors are an emerging class of energy storage materials that offer an attractive compromise between the energy density of batteries and power density of electric double-layer capacitors. Decreasing particle size and increasing surface area of battery materials is a common approach for introducing pseudocapacitive behavior and increasing power density. However, in many cases, as the crystal size is reduced, lattice disorder of unknown extent is also introduced, making it difficult to characterize the relative contribution of size and disorder to fast-charging performance. Here, in this work, a series of nanostructured MoS 2 materials are synthesized with different crystallite sizes and degrees of crystallinity to decouple the effects of size and disorder on charge/discharge kinetics. The extent and type of disorder in each material is quantified by total X-ray scattering experiments and pair distribution function analyses. Electrochemical characterization, including galvanostatic rate capability, cyclic voltammetry, and various kinetic analyses, are used to demonstrate that both decreasing particle size and introducing lattice disorder are effective strategies for increasing charge storage kinetics, and that the effects are additive. Finally, operando X-ray diffraction measurements show that both size and disorder can be used suppress first-order Li + intercalation-induced phase transitions, a key feature for enabling pseudocapacitive charge storage.

36 MATERIALS SCIENCE↗

Fine‐Tuning Alkyl Chains on Quinoxaline Nonfullerene Acceptors Enables High‐Efficiency Ternary Organic Solar Cells with Optimizing Molecular Stacking and Reducing Energy Loss

Abstract Material design of guest acceptor is always a big challenge for improving the efficiency of ternary organic solar cells (OSCs). Here, a pair of isomeric nonfullerene acceptors based on quinoxaline core, Qx–p‐C 7 H 8 O and Qx–m‐C 7 H 8 O, is designed and synthesized. By moving the alkoxy chain attached on side phenyl frommeta‐position topara‐position, both π–π stacking distance and crystallinity are enhanced simultaneously. They obtain the uplifted lowest unoccupied molecular orbital level. Compared to Qx–m‐C 7 H 8 O, Qx–p‐C 7 H 8 O exhibits wider absorption spectrum and higher extinction coefficient. Using D18‐Cl:N3 as host materials, the addition of guest acceptor Qx–p‐C 7 H 8 O significantly improves the power conversion efficiency (PCE) from 17.61% to 18.49% because of higher open‐circuit voltage (0.875 V) and short‐circuit current density (27.85 mA cm −2 ). This can be attributed to the faster exciton dissociation, more balanced carrier mobility, fine fiber morphology, and lower energy loss in the ternary devices. However, Qx–m‐C 7 H 8 O‐based ternary device achieves relatively low PCE of 17.17% because this device shows extremely low electron mobility. The results indicate that molecular stacking, film morphology, etc., can be effectively modulated by fine‐tuning the side chains of guest materials, which may be an effective design rule for further improving the PCE of OSCs.

Chemistry↗

High‐Pressure Synthesis of Ultra‐Incompressible, Hard and Superconducting Tungsten Nitrides

Abstract Transition metal nitrides, particularly those of 5 d metals, are known for their outstanding properties, often relevant for industrial applications. Among these metal elements, tungsten is especially attractive given its low cost. In this high‐pressure investigation of the W–N system, two novel ultra‐incompressible tungsten nitride superconductors, namely W 2 N 3 and W 3 N 5 , are successfully synthesized at 35 and 56 GPa, respectively, through a direct reaction between N 2 and W in laser‐heated diamond anvil cells. Their crystal structure is determined using synchrotron single‐crystal X‐ray diffraction. While the W 2 N 3 solid's sole constituting nitrogen species are N 3‐ units, W 3 N 5 features both discrete N 3‐ as well as N 2 4‐ pernitride anions. The bulk modulus of W 2 N 3 and W 3 N 5 is experimentally determined to be 380(3) and 406(7) GPa, and their ultra‐incompressible behavior is rationalized by their constituting WN 7 polyhedra and their linkages. Importantly, both W 2 N 3 and W 3 N 5 are recoverable to ambient conditions and stable in air. Density functional theory calculations reveal W 2 N 3 and W 3 N 5 to have a Vickers hardness of 30 and 34 GPa, and superconducting transition temperatures at ambient pressure (50 GPa) of 11.6 K (9.8 K) and 9.4 K (7.2 K), respectively. Additionally, transport measurements performed at 50 GPa on W 2 N 3 corroborate with the calculations.

Chemistry↗