Borophene Nanosheet Research Articles

Synthesis and Anisotropic Memristive Behavior of Borophene Nanosheets

AbstractNeuromorphic computing, marked by its parallel computational abilities and low power usage, has become pivotal in advancing artificial intelligence. However, the advancement of neuromorphic computing has faced significant obstacles due to the performance limitations of traditional memory devices struggling with high power consumption and limited reliability. Two‐dimensional (2D) materials have been extensively investigated as high‐performance memristive materials, but they are often restricted by fixed memristive properties, which complicate circuit design and limit flexibility. Here, we report that multilayer borophene nanosheets represent a breakthrough material, displaying anisotropic variable memristive properties. The nanosheets, comprising semiconductor α’‐4H‐borophene sheets and metal β12‐borophene sheets, have been synthesized on aluminum foil surface through chemical vapor deposition method. The multilayer borophene nanosheets exhibit volatile memory behavior in the vertical direction and non‐volatile memory behavior in the planar direction. This innovative class of 2D nanosheets not only overcomes the limitations of conventional memory devices but also expands the potential applications of borophene‐based memories in information storage and in‐memory computing.

Synthesis and Anisotropic Memristive Behavior of Borophene Nanosheets.

Neuromorphic computing, marked by its parallel computational abilities and low power usage, has become pivotal in advancing artificial intelligence. However, the advancement of neuromorphic computing has faced significant obstacles due to the performance limitations of traditional memory devices struggling with high power consumption and limited reliability. Two-dimensional (2D) materials have been extensively investigated as high-performance memristive materials, but they are often restricted by fixed memristive properties, which complicate circuit design and limit flexibility. Here, we report that multilayer borophene nanosheets represent a breakthrough material, displaying anisotropic variable memristive properties. The nanosheets, comprising semiconductor α'-4H-borophene sheets and metal β12-borophene sheets, have been synthesized on aluminum foil surface through chemical vapor deposition method. The multilayer borophene nanosheets exhibit volatile memory behavior in the vertical direction and non-volatile memory behavior in the planar direction. This innovative class of 2D nanosheets not only overcomes the limitations of conventional memory devices but also expands the potential applications of borophene-based memories in information storage and in-memory computing.

Integration of 2D borophene into semiconducting N, P, S, and F-doped 1D carbon for energy storage and conversion devices

Innovative energy storage and high-performing conversion devices are urgently required to meet global energy issues. In this study, we synthesized and characterized a nitrogen, phosphorus, sulfur, and fluorine-doped one-dimensional carbon (NPSF@C) integrated with two-dimensional borophene (Bph) nanosheets, forming a nanocomposite (NPSF@C/Bph). The physicochemical and structural characterization confirmed borophene’s successful doping and integration into the NPSF@C matrix. Density Functional Theory (DFT) analysis indicated that the doping of heteroatoms and the integration of Bph increased the number of conduction bands in NPSF@C/Bph, effectively reducing the band gap of the material from 1.99 eV (MWCNT) and 1.43 eV (Bph) to 0.067 eV. This transformation was attributed to the introduction of localized states near the Fermi level and an enhanced density of states, resulting in a metal-like behavior for the NPSF@C/Bph composite. The NPSF@C/Bph composite demonstrated a specific surface area of 1962.78 m2/g and a pore volume of 1.2423 cm3/g, significantly enhancing its electrochemical performance. The composite showed a high specific capacitance of 837F/g at a current density of 1 A/g and retained 92.72 % of its initial capacitance after 10,000 cycles. It also exhibited a high energy density of 78.28 Wh/kg and a power density of 4545 W/kg in a symmetric supercapacitor device. Additionally, electrochemical tests revealed that the NPSF@C/Bph composite exhibited a lower overpotential and higher current density for both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) compared to its counterparts. Specifically, the overpotential for OER is 283 eV, and HER is 73 mV at a current density of 10 mA/cm2. The Tafel slopes were 63 mV/dec for OER and 67 mV/dec for HER, indicating superior reaction kinetics.

Power dependent tunable optical nonlinearity in Iron oxide/Borophene core-shell nanoparticles under ultrashort laser excitation

Two-dimensional (2D) nanomaterials find immense applications in ultrafast photonics and optical switching systems due to their fascinating nonlinear optical (NLO) characteristics. This work presents a systematic investigation of laser power-dependent nonlinear optical characteristics of borophene nanosheets in a core-shell nanostructure. For this purpose, we have synthesized Borophene encapsulated Iron oxide (Fe3O4) core-shell nanoparticles (Fe3O4/Borophene CSNPs). The CSNPs were synthesized by mixing and annealing sodium borohydride (NaBH4) as a boron precursor with iron oxide nanoparticles (Fe3O4 NPs) in a controlled environment using chemical vapor deposition technique (CVD) followed by characterization using XRD, FTIR Spectroscopy, UV–vis absorption spectroscopy, TEM, SEM, and EDX techniques. Magnetic properties were analyzed by a vibrating sample magnetometer (VSM) which shows that the saturation magnetization of Fe3O4 NPs increases after being encapsulated in borophene nanosheets. The role of borophene in modifying the NLO characteristics of Fe3O4/Borophene CSNPs was studied using a power-dependent Z-scan technique utilizing ultrashort (femtosecond) laser pulses at a wavelength of 800 nm in both open and close aperture configuration. It was found that borophene-coated Fe3O4 NPs reveal tunable NLO properties that resemble the NLO characteristics of borophene nanosheets with enhanced features. This provides insights into an interaction between materials in NLO phenomena and illustrates the distinctive performance of the core-shell nanostructure. The tunable NLO properties of Fe3O4/Borophene CSNPs offer an innovative approach for developing optoelectronics and ultrafast nonlinear photonic devices.

A computational investigation on the adsorption behavior of bromoacetone on B36 borophene nanosheets

A computational investigation on the adsorption behavior of bromoacetone on B36 borophene nanosheets

Molecular temperature descriptors as a novel approach for QSPR analysis of Borophene nanosheets.

Borophene nanosheets appear in various sizes and shapes, ranging from simple planar structures to complicated polyhedral formations. Due to their unique chemical, optical, and electrical properties, Borophene nanosheets are theoretically and practically attractive and because of their high thermal conductivity, boron nanosheets are suitable for efficient heat transmission applications. In this paper, temperature indices of borophene nanosheets are computed and these indices are employed in QSPR analysis of attributes like Young's modulus, Shear modulus, and Poisson's ratio of borophene nanosheets and borophene β12 sheets. The regression model for the F-Temperature index is discovered to be the best fit for shear modulus, the reciprocal product connectivity temperature index is discovered to be fit for Poisson's ratio and the second hyper temperature index is discovered to be fit for Young's modulus based on the correlation coefficient.

The effect of transition metal ion implantation on the structural and optical properties of few-layered borophene

Borophene, a monometallic two-dimensional layered material has gained significant attention due to its exceptional electrical and optical properties. Despite this, borophene layers tend to restack; retards ionic conductivity, imperative for practical applications. Thus, by introducing large-sized dopants into borophene nanosheets using an ion implantation technique has been acknowledged. Accordingly, herein, structural and electronic engineering of borophene has been done with implantation of copper (Cu) ions at various fluence rates (5 × 1012, 5 × 1013, 5 × 1014 and 5 × 1015 ions-cm−2 respectively) using 1μA current at a low energy of 80 keV. The Cu insertion between borophene interlayers prevents self-restacking; providing surfacial active sites with tunable work function and decreased band gap of pristine borophene, thereby increasing charge transport ability. Further, the structural properties of implanted borophene were characterized through Raman spectroscopy, FT-IR spectroscopy and optical properties using UV–Vis and photoluminescence studies. Also, I-V measurements were conducted to study the electrical properties. Hence, ion implantation helps in significantly enhance the electrical conductivity and transportation properties of borophene.

Aluminum-Activated Borophene Nanosheets with Enhanced Oxidation Resistance for Nanoelectronic Devices

Aluminum-Activated Borophene Nanosheets with Enhanced Oxidation Resistance for Nanoelectronic Devices

Incorporation of Pd Catalyst into Highly Effective Borophene Nanosheet Co-Catalyst for Electrokinetics and Electrochemical Oxygen Reduction Reactions

To improve the performance of the system, it is of great importance to develop efficient catalysts for ethanol (EtOH) electro-oxidation. Pd/B electrocatalyst was synthesized using a sonochemical method. Structural and electrochemical properties of the prepared nanomaterial were investigated using electrochemical and physical techniques such as Raman spectroscopy, electrochemical impedance spectroscopy (EIS), x-ray diffraction (XRD), zetersizer, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HR-TEM) and energy-dispersive x-ray spectroscopy (EDS) and cyclic voltammetry (CV). FTIR confirmed all the functional groups of carbon black, Pd/C, borophene, and Pd/B, and the crystallinity was investigated using XRD. EIS showed that Pd/B has a faster charge transfer and, through investigation using CV, Pd/B showed a more negative onset potential and higher current (−0.76 V vs. Ag|AgCl; 0.07 mA) than Pd/C (−0.65 V vs. Ag|AgCl; 0.05 mA), indicating a more catalytic behavior and tolerance of Pd/B. The active sites could be attributed to the addition of borophene. During the anodic sweeping direction of Pd/B electrocatalyst, it was observed that the ratio of backward peak current (Ibwd) to forward peak current (Ifwd), (Ibwd/Ifwd) of in a 2 M of NaOH + 2 M of EtOH is almost equal to (Ibwd/Ifwd) 1 which shows excellent tolerance of Pd/B to poisoning by ethanol intermediate species. The electron transfer rate (Ks) values for Pd/B at 0.1 M, 0.5 M, 1 M, 1.5 M, and 2 M were estimated to be 4.50 × 10−13 s−1, 1.08 × 10−12 s−1, 4.28 × 10−13 s−1, 5.25 × 10−14 s−1 and 9.35 × 10-14 s−1. At 2 M there is a faster electron transfer than at other concentrations which is also evidenced by the obtained diffusion values (D) of the system which were found to be 2.92 × 10−7 cm2 s−1, 4.72 × 10−8 cm2 s−1, 4.82 × 10−8 cm2 s−1, 1.22 × 10−7 cm2 s−1, and 9.12 × 10−8 cm2 s−1. The electrochemically active surface area (ECSA) is strongly related to intrinsic activity, Pd/B (1.85 cm2/mg × 10−5 cm2/mg) denotes the highest Pd-O stripping charge than Pd/C (1.13 cm2/mg × 10−5 cm2/mg).

Hydrogenation driven ultra-low lattice thermal conductivity in β 12 borophene

Borophene gathered large interest owing to its polymorphism and intriguing properties such as Dirac point, inherent metallicity, etc but oxidation limits its capabilities. Hydrogenated borophene was recently synthesised experimentally to harness its applications. Motivated by experimental work, in this paper, using first-principles calculations and Boltzmann transport theory, we study the freestanding β 12 borophene nanosheet doped and functionalised with hydrogen (H), lithium (Li), beryllium (Be), and carbon (C) atoms at different β 12 lattice sites. Among all possible configurations, we screen two stable candidates, pristine and hydrogenated β 12 borophene nanosheets. Both nanosheets possess dynamic and mechanical stability while the hydrogenated sheet has different anisotropic metallicity compared to pristine sheet leading to enhancement in brittle behaviour. Electronic structure calculations reveal that both nanosheets host Dirac cones (DCs), while hydrogenation leads to shift and enhancement in tilt of the DCs. Further hydrogenation leads to the appearance of additional Fermi pockets in the Fermi surface. Transport calculations reveals that the lattice thermal conductivity changes from 12.51 to 0.22 W m−1 K−1 (along armchair direction) and from 4.42 to 0.07 W m−1 K−1 (along zigzag direction) upon hydrogenation at room temperature (300 K), demonstrating a large reduction by two orders of magnitude. Such reduction is mainly attributed to decreased phonon mean free path and relaxation time along with the enhanced phonon scattering rates stemming from high frequency phonon flat modes in hydrogenated nanosheet. Comparatively larger weighted phase space leads to increased anharmonic scattering in hydrogenated nanosheet contributing to ultra-low lattice thermal conductivity. Consequently, hydrogenated β 12 nanosheet exhibits a comparatively higher thermoelectric figure of merit (∼0.75) at room temperature along armchair direction. Our study demonstrates the effects of functionalisation on transport properties of freestanding β 12 borophene nanosheets which can be utilised to enhance the thermoelectric performance in two-dimensional (2D) systems and expand the applications of boron-based 2D materials.

DNA Aptamers on Borophene Nanosheets as an Electrochemical System for Omicron Detection

DNA Aptamers on Borophene Nanosheets as an Electrochemical System for Omicron Detection

Highly bendable and smoke free degradable nanomaterials modified paper based electrochemical biosensor for efficient detection of protein biomarker

Here, we report results of the studies related to the fabrication of nanomaterial modified paper [Whatman paper modified with poly(3,4-ethylenedioxythiophene):poly(4-styrene sulfonate) (PEDOT:PSS) and Borophene nanosheets] based biosensor for proteinaceous Serum Amyloid A (SAA) biomarker detection. For the fabrication of stable and cost-efficient nanomaterial modified conducting paper, we used simple dip coating method followed by solvent treatment. The incorporation of Borophene nanosheets onto the conducting paper resulted in enhance electrochemical performance, flexibility and signal stability. The flexibility of fabricated electrode is validated via bending and folding studies; it continues to maintain conductivity even after being folded 40 times. Furthermore, this paper sensor may be quickly and properly disposed of by simple burning method without emitting smoke. It was also observed that no any harmful/heavy element was present after disposal of the paper sensor. During fabrication of paper based sensor, anti-SAA was physically immobilized and further bovine serum albumin (BSA) was used to block the non-specific binding sites. To examine structural and morphological features of the synthesized material and the fabricated paper electrodes; X-ray diffraction, transmission electron microscopy, scanning electron microscopy, contact angle, and Fourier-transform infrared spectroscopy were used. The fabricated immunoelectrode (BSA/anti-SAA/Borophene/CP) is highly efficient to detect SAA with ultralow limit of detection of 0.49 ng mL−1, wider linear detection range in between 1 ng mL−1 - 60 µg mL−1 and high durability of 42 days. Finally, SAA protein in spiked serum samples was analyzed using the fabricated immunosensor, and the obtained results show good correlation with the standard SAA protein samples.

Hazardous (NO2, NO, CO, CO2, SO2, and NH3) molecules interacting with Pt-decorated [formula omitted] borophene. A first-principle study

First principles study within the density functional theory is addressed to study the energetic and electronic properties of β12 borophene nanosheet with adsorbed platinum (Pt). In addition, the potential use of Pt-decorated borophene as a catalytic material and molecular sensor is also studied. We observed that the most stable configuration (lower binding energy) for Pt be adsorbed on the β12 borophene nanosheet is on the center of a hexagon (Eb=−4.473 eV). The presence of Pt adsorbed does not modify the metallic properties of β12 borophene but gives rise to new electronic levels resonant with the conduction band (around 2.0 eV above the Fermi energy). The calculated Bader charge show a charge transference of 0.567 electrons from borophene to the Pt atom. When molecules are adsorbed on the Pt atom, the calculated adsorption energies, electronic density of states (DOS), work function, and charge transference show that there is a strong interaction between hazardous molecules and Pt-decorated β12 borophene. The only exception is CO2, which interact with Pt-decorated borophene via van der Waals forces. The comparative analysis of the DOS before and after the molecular adsorption shows that the Pt levels are spread out and shifted to the Fermi energy after the molecular adsorption. The results of the DOS, charge transference, as well as the change in the work function allow us to infer that Pt-decorated β12 borophene is a potential material to be used as catalyst and gas sensing.

Li-intercalation chemistry of few-layer borophene with ultrahigh capacity and fast kinetics

Two-dimensional borophene nanosheets (2D BNSs) have been theoretically predicted to be an ideal lithium-storage material owing to their high theoretical capacity and low Li-ion diffusion energy barrier. However, the lithium-storage capability and mechanism of 2D BNSs have not yet been reported until now. Herein, ultrathin 2D BNSs (<2 nm) were successfully fabricated by sonication-assisted liquid exfoliation, and further explored as a Li-storage host. The ultrathin BNSs delivered an ultrahigh capacity of 782.9 mAh/g over 500 cycles at 167 mA/g. The Li-storage mechanism of BNSs was revealed by in-situ X-ray diffraction and the results showed that the Li+ ions intercalate/deintercalate along (205) plane with the formation of interstitial compound of Li0.48B. The charge storage behavior of 2D BNSs was also proved to be dominated by a pseudocapacitance-control process, which contributes to the high-rate capability. This work would accelerate the exploration of emerging 2D materials for high-energy–density lithium-ion batteries.

A novel perspective for M-polynomials to compute molecular descriptors of borophene nanosheet

Nanomaterials feature exceptional, one-of-a-kind qualities that might be used in electronics, medicine, and other industries. Two-dimensional nanomaterials called borophene have a variety of intriguing characteristics, which helped them to leave an indelible impression in the fields of chemistry, material science, nanotechnology, and condensed matter physics. The concept of modelling the structure of a molecule or chemical network to a chemical graph and then quantitatively analysing them with the aid of topological descriptors was a major advance in the fields of mathematics and chemistry, with a wide range of applications. M-polynomial approach is a very versatile and quick method for computing the degree-based descriptors of chemical graphs or networks. The degree-based descriptors of the beta _{12}-Borophene nanosheet are established in this study utilising the M-polynomial technique. A program code that enables to generate the M-polynomial of any chemical structure was developed in Java platform and the same is displayed. At the conclusion, the numerical and graphical comparison based on the identified analytic expressions is also provided. Additionally, the QSPR analysis was also carried out and the outcoms are presented therein.

Blue light emitting piezoelectric few-layered borophene nanosheets for flexible nanogenerators

Piezoelectric response from two-dimensional layered materials with semiconducting properties is important for developing nanogenerators, piezotronics, and piezophototronics devices. However, experimental observation of piezoelectricity and semiconductor properties in monoatomic borophene has been a key challenge for the fabrication of nanogenerator devices. Here, we discover the non-centrosymmetric blue light emitting piezoelectric properties of few layered monoatomic borophene nanosheets. We develop the flexible piezoelectric nanogenerator using few layered borophene nanosheets in polydimethylsiloxane polymer, producing an output voltage of 8 V without electrical poling. The material exhibits a high piezoelectric charge coefficient (d33) of 86 pm V−1 and shows band gap opening with a high band gap of 2.32 eV. Surprisingly, the borophene nanosheets exhibit blue light emission under UV light illumination. Under UV light illumination, the device dramatically improves output performance. We find that the material exhibits a high dielectric constant of about 125 at low frequency.

Prediction of gas adsorption on [formula omitted] borophene: A density functional theory study

In this work, we present the electronic transport properties of χ3 borophene nanosheets in the presence of the CO, CO2, NO, NH3 gas molecules. Adsorption energy, adsorption distance, charge transfer, recovery time, the density of states, the current–voltage, the relative current change, the transmission spectrum and the STM image of the structures have been focused. The gas sensor capability of two-dimensional χ3 borophene nanosheet is investigated by calculation of the quantum transport in the framework of the nonequilibrium Green’s function formalism within the density functional theory. The results explore that χ3 borophene nanosheets are sensitive toward the NO and the NH3 gas adsorbates to the CO and CO2 ones.

Pd nanoparticles-decorated borophene nanosheets for intrinsic polarization-induced visible light photocatalysis

The electron transfer from Pd to boron in the Pd–B heterostructure creates an intrinsic polarization that facilitates effective separation of photogenerated charge carriers for photocatalytic degradation of organic pollutants.

Light-induced tumor theranostics based on chemical-exfoliated borophene

Among 2D materials (Xenes) which are at the forefront of research activities, borophene, is an exciting new entry due to its uniquely varied optical, electronic, and chemical properties in many polymorphic forms with widely varying band gaps including the lightest 2D metallic phase. In this paper, we used a simple selective chemical etching to prepare borophene with a strong near IR light-induced photothermal effect. The photothermal efficiency is similar to plasmonic Au nanoparticles, with the added benefit of borophene being degradable due to electron deficiency of boron. We introduce this selective chemical etching process to obtain ultrathin and large borophene nanosheets (thickness of ~4 nm and lateral size up to ~600 nm) from the precursor of AlB2. We also report first-time observation of a selective Acid etching behavior showing HCl etching of Al to form a residual B lattice, while HF selectively etches B to yield an Al lattice. We demonstrate that through surface modification with polydopamine (PDA), a biocompatible smart delivery nanoplatform of B@PDA can respond to a tumor environment, exhibiting an enhanced cellular uptake efficiency. We demonstrate that borophene can be more suitable for safe photothermal theranostic of thick tumor using deep penetrating near IR light compared to gold nanoparticles which are not degradable, thus posing long-term toxicity concerns. With about 40 kinds of borides, we hope that our work will open door to more discoveries of this top-down selective etching approach for generating borophene structures with rich unexplored thermal, electronic, and optical properties for many other technological applications.

Freestanding α-rhombohedral borophene nanosheets: preparation and memory device application

Borophene has attracted extensive interests owing to its distinct structural, electronic and optical properties for promising potential applications. However, the structural instability and need of metal substrate for deposition of borophene seriously restrict the exploration of its exceptional physical and chemical properties and further hamper its extensive applications towards high-performance electronic and optoelectronic devices. Here, we reported the synthesis of high-quality freestanding α-rhombohedral borophene nanosheets by a facile probe ultrasonic approach in different organic solvents. The results show that the nanosheets have high-quality in ethanol solution and have an average lateral size of 0.54 μm and a thickness of around 1.2 nm. Photoluminescence spectra indicate that a strong quantum confinement effect occurs in the nanosheets, which caused the increase of the band gap from 1.80 eV for boron powders and 2.52 eV for the nanosheets s. A nonvolatile memory device based on the nanosheets mixed with polyvinylpyrrolidone was fabricated, which exhibited a good rewriteable nonvolatile memory behavior and good stability.