High Cohesive Energy Research Articles

Multi-bioinspired alginate-based gel coatings formed by dynamic metal–ligand assembly for enhancing foliar affinity and rain-fastness of pesticides

Insufficient deposition of pesticide droplets and rain erosion are significant factors in excessive pesticide wastage and pose a significant threat to public health and the ecological environment. Inspired by the adhesion mechanism of marine mussels and mayfly larvae, we developed a gel coating to improve pesticide retention efficiency and resistance to rainwater washout by sequential spraying polydopamine-functionalized alginate and Fe3+ ions onto the target leaf surface (SA-DA/Fe3+). Abundant catechol groups provide strong molecular-level interfacial bridging for alginate derivates, while the gel coating contains flexible, deformable, and complex nanoscale networks, inducing mutual coupling with micro/nanostructures on the leaf surface, ultimately resulting in the removal of the interface void and the improvement of deposition capacity at multiple scales. The gel coating shows high cohesive energy to better resist rain rinsing due to the dense carboxyl-Fe3+ and catechol-Fe3+ coordination bonds in the network architecture. By combining the above effects, the pesticide retention rate of SA-DA/Fe3+ gel coating on foliage could reach about 97 % after rain erosion and immersion. In addition, the SA-DA/Fe3+ gel coating can also achieve the sensitive photo-control effect of pesticides due to the intrinsic photosensitivity of the iron-carboxylate system. Using an alginate-based gel coating as a promising strategy for improving pesticide utilization, addressing the issues of easy runoff, susceptibility to erosion, and uneven coverage in traditional pesticide droplet form, thus bridging the fields of bionic materials science, bio-macromolecular chemistry, and agricultural science.

Electrical Resistivity Modification of Electrodeposited Mo and Mo–Co Nanowires for Interconnect Applications

Achieving historically anticipated improvement in the performance of integrated circuits is challenging, due to the increasing cost and complexity of the required technologies with each new generation. To overcome this limitation, the exploration and development of novel interconnect materials and processes are highly desirable in the microelectronics field. Molybdenum (Mo) is attracting attention as an advanced interconnect material due to its small resistivity size effect and high cohesive energy; however, effective processing methods for such materials have not been widely investigated. Here, we investigate the electrochemical behavior of ions in the confined nanopores that affect the electrical properties and microstructures of nanoscale Mo and Mo–Co alloys prepared via template-assisted electrodeposition. Additives in an electrolyte allow the deposition of extremely pure metal materials, due to their interaction with metal ions and nanopores. In this study, boric acid and tetrabutylammonium bisulfate (TBA) were added to an acetate bath to inhibit the hydrogen evolution reaction. TBA accelerated the reduction of Mo at the surface by inducing surface conduction on the nanopores. Metallic Mo nanowires with a 130 nm diameter synthesized through high-aspect-ratio nanopore engineering exhibited a resistivity of (63.0 ± 17.9) μΩ·cm. We also evaluated the resistivities of Mo–Co alloy nanowires at various compositions toward replacing irreducible conventional barrier/liner layers. An intermetallic compound formed at a Mo composition of 28.6 at%, the resistivity of the Mo–Co nanowire was (58.0 ± 10.6) μΩ·cm, indicating its superior electrical and adhesive properties in comparison with those of conventional barriers such as TaN and TiN. Furthermore, density functional theory and non-equilibrium Green’s function calculations confirmed that the vertical resistance of the via structure constructed from Mo-based materials was 21% lower than that of a conventional Cu/Ta/TaN structure.

Star‐Shaped Organic Semiconductor with Extraordinary Thermomechanical Property and Solution Processability for Stable Perovskite Solar Cells

AbstractAchieving the desired thermomechanical properties for highly solution‐processable organic semiconductors is challenging but crucial for heat tolerance of emerging optoelectronic devices. To this end, the successful synthesis of triphenylene–ethylenedioxythiophene‐dimethoxytriphenylamine (TP–ETPA), a star‐shaped organic semiconductor, is reported through a direct arylation reaction that involves ETPA, an electron donor, being grafted densely onto TP, which possesses six electron‐equivalent functionalization sites. Remarkably, TP–ETPA exhibits significantly improved hole mobility compared to 2,2′,7,7′‐tetrakis(N,N‐di‐p‐methoxyphenyl‐amine)‐9,9′‐spirobifluorene (spiro‐OMeTAD) at a given hole density, owing to its lower energetic disorder, larger average centroid distance, and smaller reorganization energy. TP–ETPA, with a molecular weight of 2888 Da and lacking flexible chains, demonstrates extraordinary solubility in nonpolar solvents, enabling the formation of dense, pinhole‐free films through solution codeposition with an air‐doping promoter. By utilizing the p‐doped TP–ETPA composite as the hole transport layer, perovskite solar cells with an average power conversion efficiency of 23.4% are successfully fabricated. Notably, these devices display significantly enhanced operational stability and thermal stability at 85 °C. Molecular dynamics simulations reveal that the TP–ETPA‐based hole transport layer possesses a high cohesive energy density, resulting in a large elastic modulus and slow diffusion of external species.

Li-decorated graphdiyne for ultrahigh-performance CO2 capture and separation over N2

The development of CO2 adsorbents with high adsorption and separation performances is important to solve severe environmental problems. Herein, two-dimensional graphdiyne acetylene rings doped with different concentrations of lithium atoms (1/2/6Li-GDYs) were introduced as potential adsorbents for CO2 capture and separation by using Grand Canonical Monte Carlo and Density Functional Theory methods. According to the structure analysis, Li atoms could stably bind to GDY with a binding energy of 1.04 – 2.77 eV/atom; 1/2/6Li-GDYs had high cohesive energy of 7.02 – 7.54 eV/atom. Electronic structure analysis confirmed the large charge transfer and strong interaction between Li atoms and GDY. The pore physical properties of Li-GDYs indicated that the pore volume, porosity, and pore size provided a favorable environment for CO2 adsorption. Among Li-GDYs, 2/6Li-GDYs exhibited an ultra-high CO2 adsorption capacity of 11.91 mmol/g at 298 K and 100 kPa, and was superior to other metal-modified adsorbents. The CO2/N2 selectivity in 1/2/6Li-GDYs reached ∼ 168, ∼311, and ∼ 1021 at 298 K and 100 kPa. Gas distribution analysis revealed a broad CO2 distribution consisting of multilayer adsorption peaks around Li and adjacent C atoms, illustrating the significant effect of Li and Li-connected C atoms on CO2 adsorption. Interaction analysis showed that Li doping enhanced the CO2-framework interaction more significantly than the N2-framework interaction, resulting in ultra-high CO2 adsorption capacity and CO2/N2 selectivity. The results of this work highlight 1/2/6Li-GDYs as ultrahigh-performance adsorbent materials for CO2 adsorption and separation over N2.

Understanding of the Effect of the Adsorption of Atom and Cluster Silver on Chitosan: An In Silico Analysis.

In this work, the structural, electronic, and optical stability properties of the chitosan monomer (M-Ch) and atomic silver complex are reported, as well as a unitary cell of a silver cluster in the gas phase and acetic acid. The generalized gradient approximation HSEh1PBE/def2-TZVPP50 results established the structures' anionic charge (Q = -1|e|) and the doublet state (M = 2). The high cohesive energy indicates structural stability, and the quantum-mechanical descriptors show a high polarity and low chemical reactivity. Also, the quantum-mechanical descriptors present a low work function that shows the structures are suitable for applications in light-emitting diodes. Finally, the electronic behavior observed by the |HOMO-LUMO| gap energy changes depending on the atomic silver incorporated into the complex.

Triple-induced gardenia fruit extract-enriched gelatin/polysaccharides microgels for O/W emulsions, and food 3D printing

Gardenia fruit extract like gardenia blue is untable under light exposure and its application need expansion. Gardenia blue was proposed to be stabilized in triple-induced microgels from cooperative effects of gelatin, β-cyclodextrin and chitooligosaccharide, and its emulsifying ability and 3D printing potential were subesequently explored. The synergetic effects on gardenia blue due to the intermolecular interactions including hydrogen bonding and electrostatic interaction, contributed to the high UV irradiation stability of complexes. The complex microgels could absorb onto oil-water interface with emulsifying property, and the obtained high internal phase emulsions (HIPEs) illustrated outstanding centrifugal stability and great storage stability with low and uniform optical microscopic droplet diameters. The obtained HIPEs possessed excellent shearing thinning properties, excellent structure reversibility, high-degree reticulation, outstanding thixotropy, great elasticity, high cohesive energy and mechanical strength. 3D printing of HIPEs onto food also demonstrated high shape fidelity with low deviation. The findings illustrate the way of stabilizing gardenia blue in microgels by triple synergies, demonstrate the potential as stabilizer for developing HIPEs, and offered reference for highly-added-value utilization in the personalized 3D food products.

Atomic diffusion, segregation, and grain boundary migration in nickel-based alloys from molecular dynamics simulations

Grain boundary diffusion and metal mobility in alloys control material performance in many applications and yet remain poorly understood at a mechanistic level. With advances in accessible time and length scales for computational molecular simulations, and recent force field developments, we now possess tools to help unravel those mechanisms. Using large-scale molecular dynamics simulations, here we examined vacancy-mediated diffusion processes in Ni-5Cr alloy with low and high-energy grain boundaries. We show that atomic diffusion inside the grain boundary plane is about four times higher than bulk diffusion, at any temperature, and exhibits a typical Arrhenius behavior with a very small energy barrier (∼0.8 eV for Cr and 0.7 eV for Ni within 1300–1600 K). Additionally, the fastest diffusing species inverts; Cr diffusion was faster than Ni in the bulk but slower in the grain boundaries. This is attributed to the creation of high cohesive energy clusters of Cr at the grain boundary. Grain boundary migration was also observed to be temperature dependent and appears to be two times higher in the 5% Cr alloy than in pure Ni, highlighting the important role of the alloying element on grain boundary motion.

A distinctive strategy of Sb doped quaternary oxide cathodes materials toward energy storage of electric equipment for sodium-ion batteries

The poor cycle stability and rate capability for sodium-ion batteries is largely due to electrochemical irreversibility and sluggish mobility of Na+ in the cathode materials. Herein, a new strategy of introducing Sb ions into the ternary oxide NiMnTi-based layer-structured cathode material is designed. Reversible phase transition in this cathode NMTSb0.03 restraint the rapid capacity decay issued from intense volume variation, exhibiting a reversible capacity of 147.8 mAh g−1 and retaining 103.5 mAh g−1 over 200 cycles at 1C. The enough space after Sb substitution allows the effective accommodation of Na+ intercalation and deintercalation, affording a specific capacity of 90 mAh g−1 at 8C. The improvement is attributed to the enhanced Na+ diffusion kinetics with the meliorative equilibrium conductance and the higher cohesive energy after Sb doping. Considering its simple preparation and scale-up capability, the O3-type NaNi0.5Mn0.3Ti0.2O2 with Sb5+may find extensive applications in designing electrode for sodium-ion batteries.

B3S2 monolayer as an anode material for Na/K-ion batteries: a first-principles study.

Two-dimensional (2D) materials used as anodes in metal-ion batteries have attracted increased attention due to their high specific surface area, abundant active sites and good electronic properties. Searching for 2D materials with high storage capacities and low diffusion energy barriers is one of the most effective ways to design novel anode materials. In this work, based on first-principles calculations, we design a new 2D B3S2 monolayer with high thermodynamic and dynamic stability. The obtained B3S2 monolayer has a high cohesive energy, ensuring the feasibility of experimental synthesis. These characteristics of the B3S2 monolayer prompt us to explore its application as an anode material. The B3S2 monolayer exhibits not only a metallic nature but also a low diffusion energy barrier (0.037 eV) and open-circuit voltage (0.09 V). More importantly, the B3S2 monolayer shows a very high theoretical capacity of 1658 mA h g-1 as an anode material for sodium-ion batteries, which is comparable to other similar or common 2D materials. All of these intriguing properties make the B3S2 monolayer a promising 2D anode material for sodium-ion batteries.

Atomic reconstruction and oxygen adsorption behavior of the pyrite (100) surface: a DFT study.

The analysis of the surface chemical behavior of pyrite is highly crucial in the fields of environmental conservation, metal extraction, and flotation separation. In this paper, the mechanism of atomic reconstruction on the pyrite surface and the adsorption behavior of O2 on a reconstructed surface are calculated by density functional theory (DFT). Different reconstruction surfaces were constructed by deleting S and Fe atoms on the (100) surface of pyrite. In addition, the geometric configuration, formation energy, binding energy, cohesion energy, and surface electronic properties of the reconstruction surface were calculated. The adsorption energies and geometric configurations of O2 on different reconstructed surfaces were also determined. The results show that under Fe-poor conditions, the charge of Fe atoms increases, and S atoms form Sn on the reconstructed surface. The binding energy between the Sn and the substrate (ideal surface) is lower, which is similar to the Sn adsorption on the substrate surface with the Fe atom as the site. Sn has high cohesive energy and is resistant to being attacked by oxidants, which leads to structural collapse, and a low affinity for O2. Under S-poor conditions, the -[Fe-S]n- plane structure formed on the reconstructed surface. The -[Fe-S]n- structure stably bonds to the substrate by an Fe-S bond, and exhibits strong binding energy. However, the -[Fe-S]n- structure has low cohesive energy and exhibits thermodynamic instability. In contrast, O2 shows a strong affinity for the -[Fe-S]n- structure, indicating that the deficiency of the S atom promotes the surface oxidation reaction. The mechanism of atomic reconstruction on the surface of pyrite is of utmost importance for understanding its surface chemical behavior.

Two-dimensional Be2Al and Be2Ga monolayer: anti-van't Hoff/Le Bel planar hexacoordinate bonding and superconductivity.

Because of the electron deficiency of boron, a triangular network with planar hexacoordination is the most common structural and bonding property for isolated boron clusters and two-dimensional (2D) boron sheets. However, this network is a rule-breaking structure and bonding case for all other main-group elements. Herein, the Be2M (M = Al and Ga) 2D monolayer with P6/mmm space group was found to be the lowest-energy structure with planar hexacoordinate Be/Al/Ga motifs. More interestingly, Be2Al and Be2Ga were observed to be intrinsic phonon-mediated superconductors with a superconducting critical temperature (Tc) of 5.9 and 3.6 K, respectively, where compressive strain could further enhance their Tc. The high thermochemical and kinetic stability of Be2M make a promising candidate for experimental realization, considering its high cohesive energy, absence of soft phonon modes, and good resistance to high temperature. Moreover, the feasibility of directly growing Be2M on the electride Ca2N substrate was further demonstrated, where its intriguing electronic and superconducting properties were well maintained in comparison with the freestanding monolayer. The Be2M monolayer with rule-breaking planar hexacoordinate motifs firmly pushes the ultimate connection of the "anti-van't Hoff/Le Bel" structure with promising physical properties.

Inert ambiance-assisted laser ablation of CVD diamond leads to enhanced surface quality and grindability

Diamond is a versatile ultimate engineering material that has been recommended for numerous purposes, especially micro mills. Laser-assisted precision grinding is substantiated to be a promising approach for fabricating diamond micro tools. Yet, in practice, the short pulses that render express elimination will deteriorate the flatness of the tool surfaces, bringing about a boost in the risk of edge collapse and a shrink in yield during the subsequent precision grinding. The tactic of ambiance-assisted laser ablation, which introduces an auxiliary gas during the irradiation to promote the ablated domain quality, is proposed in this investigation. Specifically, a raster scanning-based transient temperature distribution simulation is erected to comprehend the ablation mechanism of the chemical vapor deposition (CVD) diamond. Additionally, it can be deduced that the inert nitrogen with high cohesive energy curbs the instantaneous deflagration of oxidation on the Knudsen layer and the activity of dangling bonds that are desorbed at high temperatures. The nitrogen-assisted laser ablation of the diamond sample leads to a maximum dwindling in surface roughness of 33% compared to that with non-ambiance-assisted. Subsequently, the laser-ablated surface optimized by an inert atmosphere is precisely ground with a fine abrasive grinding wheel. The detection of the sharp cutting edge ( r β = 1.74 μm) with almost no notch and the ground flank surface with the roughness of 168 nm indicates that accessing the inert auxiliary atmosphere during ablation can enhance the surface quality of the machined diamond and the corresponding grindability.

A Self-Matting Waterborne Polyurethane Coating for PVC Artificial Leather

A type of polyester-based self-matting waterborne polyurethane (ESMWPU) with an excellent matte effect of 0.8° and transmittance of 78.5% for PVC artificial leather was synthesized. The influence of synthesis parameters, including R value, crosslinking and hydrophilic group content, on coating gloss and transmittance was investigated. Meanwhile, the properties necessary for applying water-based resins to plasticized PVC were detailed. The results demonstrated that R value, crosslinking degree and hydrophilic group content synergistically decided the morphological changes of latex particles during their film-forming process in three aspects: particle stiffness, three-dimensional structure and particle size, respectively. With optimized parameters of R = 1.9, TMP = 2 wt% and DMPA = 1.75 wt%, ESMWPU latex particles stabilized their spherical shapes without collapsing in the film-forming process and created a rough surface, resulting in a matte effect. In terms of application performance, good wetting and adhesion for ESMWPU to a plasticized PVC surface was achieved with a 2 wt% leveling agent load. Moreover, due to the high cohesion energy of ester bonds and intermolecular hydrogen bonds, this type of polyester-based ESMWPU also depicted admirable thermal adhesion resistance. All aforementioned results distinctly demonstrate a feasible yet promising paradigm for applying ESMWPU on PVC artificial leather.

Biospecific cation-π interaction by modulating molecular hydration and supramolecular structure of short peptides

This study presents novel adhesive materials that use cation-π interactions to achieve highly specific cohesive interaction under water. The materials are short length peptides based on the FKF motif flanked by different side groups. Using the surface forces apparatus, we show that the composition of the side group allows to finely tune the strength of the cohesive and adhesive energies of the peptide and its specificity, meaning its capacity to bind strongly only to substrates bearing the same peptide. The interfacial properties of these adhesive peptides are shown to strongly depend on the composition of the deposition solvent, with DMSO being the solvent of choice to achieve high cohesive and adhesive energies. This result was correlated with the supramolecular structure of the peptide film and confirmed that needle-like structures can significantly enhance the adhesion of the material. Altogether, we showed that cation-π interaction can be used efficiently to create adhesive materials that incorporate features already known for underwater adhesives such as activation via solvent displacement, as well as new ones such as specificity and supramolecular structure enhanced adhesion.

Weakening s-d orbital hybridization of metallic iridium by tungsten atoms for acidic water splitting

To economically realize proton electrolyte membrane water splitting technology, stable and high-performance oxygen evolution reaction (OER) electrocatalyst is significantly demanded. In this work, we invite tungsten atoms to metallic iridium (Ir) to weaken s-d hybridization of Ir-Ir bond due to the higher electronegativity accepting electron from Ir atoms; as a result, the adsorbed O* species become electrophilic favorable for the nucleophilic attack by H2O leading to 22 % decrement in energy barrier for the formation of OOH* species. Therefore, iridium-tungsten (IrW) electrocatalyst exhibits 3.7-fold higher turnover frequency (TOF) than metallic Ir at overpotential of 370 mV in acidic OER catalysis. Moreover, stable OER performance is recorded due to the high cohesive energy of tungsten atoms. Additionally, TOF of IrW electrocatalyst reaches 10.1 s−1 at overpotential of 100 mV in acidic hydrogen evolution reaction (HER) test, 7.6-time higher than Pt/C and metallic Ir. IrW electrocatalyst only needs 1.52 V to attain 10 mA cm−2 in acidic overall water splitting.

Monolayer C2/m−SnX ( X=P , As): An in-plane anisotropic two-dimensional direct band gap semiconductor with ultrahigh mobility, ideal IR-VIS light transparency, and high absorbance

Over the years, designing and establishing new materials with good stability, a suitable band gap, and high carrier mobility have become the focus in researching two-dimensional (2D) materials. In this paper, we predict two 2D semiconductors, $C2/m\text{\ensuremath{-}}\mathrm{Sn}X$ ($X=\text{P}$, As), using first-principles simulation. They possess excellent dynamical and thermal stability, low structural symmetry, high cohesive energy, and good flexibility for the structural properties. Regarding electronic properties, SnP and SnAs are direct band gap semiconductors with suitable band gap values. In addition, they exhibit a high carrier mobility (about $\ensuremath{\sim}{10}^{3}\text{--}{10}^{4}\phantom{\rule{4.pt}{0ex}}{\text{cm}}^{2}\phantom{\rule{0.16em}{0ex}}{\text{V}}^{\ensuremath{-}1}\phantom{\rule{0.16em}{0ex}}{\text{s}}^{\ensuremath{-}1}$). Their optical properties reveal good transparency in the infrared and visible light regions, but the primary response region of light locates in the ultraviolet area. In addition, their electronic and optical properties show different characteristics in different directions. Therefore, $C2/m\text{\ensuremath{-}}\mathrm{Sn}X$ ($X=\text{P}$, As) are 2D direct band gap semiconductors with excellent stability, a suitable band gap value, high carrier mobility, and good IR-VIS light transparency. We suggest that the group IV-V 2D semiconductor $C2/m\text{\ensuremath{-}}\mathrm{Sn}X$ ($X=\text{P}$, As) will have bright prospects in field-effect transistors, integrated circuits, the hole transport layer of solar cells, blue LEDs, and other nanoelectronic and nano-optoelectronic devices.

2D boron-nitride featuring B4 tetrahedros: An efficient photocatalyst for water splitting

Two-dimensional hexagonal boron nitride (h-BN) is an insulator with polar covalent B−N bonds. Based on current research on boron-nitrogen 2D materials and the cluster assembling method, here, we designed five novel monolayers with square lattice formed by tetrahedral B4 units covalently linked to V-group atoms, namely the B4N2, B4P2, B4As2, B4Sb2, and B4Bi2 monolayers, via first-principles calculations. Both the B4N2 and B4P2 have good stability, as demonstrated by high cohesive energies, all positive phonon modes, high in-plane Young's modulus and structural integrity through 5 ps's molecular dynamics simulations at both 300 and 500 K. Moreover, the B4P2 monolayer exhibits metallic properties, whereas the B4N2 monolayer is an indirect bandgap semiconductor with the bandgap of 2.56 eV and appropriate band edge positions, the optical adsorption in UV light region, and high electron mobility for photocatalytic water splitting. Our theoretical study adds new members of 2D boron nitrides (B4N2), which can be used as an efficient photocatalyst for water splitting.

Emergence of Rashba splitting and spin-valley properties in Janus MoGeSiP2As2 and WGeSiP2As2 monolayers

First-principles calculations are performed to study the structural stability and spintronics properties of Janus MoGeSiP2As2 and WGeSiP2As2 monolayers. The high cohesive energies and the stable phonon modes confirm that both these structures are experimentally accessible. In contrast to pristine MoSi2P4, the Janus monolayers demonstrate reduced direct bandgaps and large spin-split states at K/K’. For the monolayered Janus structure, the broken mirror symmetry with respect to the Mo/W-plane gives rise to a potential gradient normal to the basal plane, which causes difference in the work function for the two surfaces. In addition, the spin textures exposed that breaking the mirror symmetry brings Rashba-type spin splitting in the systems which can be increased by using higher atomic spin–orbit coupling. The large valley spin splitting together with the Rashba splitting in these Janus monolayer structures can make a remarkable contribution to semiconductor valleytronics and spintronics.

Designing lightweight multicomponent magnesium alloys with exceptional strength and high stiffness

Magnesium (Mg) alloys have a great potential for applications in the automobile, aerospace, and 3C industries due to their light weight, high specific strength, good conductivity, high damping capacity, and superior recyclability. However, the low strength and relatively low stiffness of Mg alloys seriously hinder their large-scale applications. In this work, a series of lightweight multicomponent Mg90.5-xAl5ZnxCu4Ce0.5 (x = 4, 8, 14, 18, and 23 at.%) alloys with high strength and high Young's modulus were designed based on the multicomponent alloys concept to obtain a high alloying degree by precipitating a large number of high Young's modulus phases, and prepared successfully by electric resistance furnace. The present results show that these alloys exhibit an excellent combination of exceptional compressive strength (up to 627 MPa) and high Young's modulus (up to 65 GPa), which is attributed to a large number of stable intermetallic phases with high cohesive energy and high Young's modulus, as verified by first-principles calculations. Our results may have implications for the design of Mg alloys and Mg-based composites with high strength and high stiffness.

Discovering Superhard B-N-O Compounds by Iterative Machine Learning and Evolutionary Structure Predictions.

We searched for new superhard B–N–O compounds with an iterative machine learning (ML) procedure, where ML models are trained using sample crystal structures from an evolutionary algorithm. We first used cohesive energy to evaluate the thermodynamic stability of varying BxNyOz compositions and then gradually focused on compositional regions with high cohesive energy and high hardness. The results converged quickly after a few iterations. Our resulting ML models show that Bx+2NxO3 compounds with x ≥ 3 (like B5N3O3, B6N4O3, etc.) are potentially superhard and thermodynamically favorable. Our meta-GGA density functional theory calculations indicate that these materials are also wide bandgap (≥4.4 eV) insulators, with the valence band maximum related to the p-orbitals of nitrogen atoms near vacant sites. This study demonstrates that an iterative method combining ML and ab initio simulations provides a powerful tool for discovering novel materials.