Thin Nanoplates Research Articles

Thickness-Dependent Magnetic Breakdown in ZrSiSe Nanoplates.

We report a study of thickness-dependent interband and intraband magnetic breakdown by thermoelectric quantum oscillations in ZrSiSe nanoplates. Under high magnetic fields of up to 30 T, quantum oscillations arising from degenerated hole pockets were observed in thick ZrSiSe nanoplates. However, when decreasing the thickness, plentiful multifrequency quantum oscillations originating from hole and electron pockets are captured. These multiple frequencies can be explained by the emergent interband magnetic breakdown enclosing individual hole and electron pockets and intraband magnetic breakdown within spin-orbit coupling (SOC) induced saddle-shaped electron pockets, resulting in the enhanced contribution to thermal transport in thin ZrSiSe nanoplates. These experimental frequencies agree well with theoretical calculations of the intriguing tunneling processes. Our results introduce a new member of magnetic breakdown to the field and open up a dimension for modulating magnetic breakdown, which holds fundamental significance for both low-dimensional topological materials and the physics of magnetic breakdown.

Step-by-Step Nanoscale Top-Down Blocking and Etching Lead to Nanohexapods with Cartesian Geometry.

In this research, we designed a stepwise synthetic method for Au@Pt hexapods where six elongated Au pods are arranged in a pairwise perpendicular fashion, sharing a common point (the central origin in a Cartesian-coordinate-like hexapod shape), featured with tip-selectively decorated Pt square nanoplates. Au@Pt hexapods were successfully synthesized by applying three distinctive chemical reactions in a stepwise manner. The Pt adatoms formed discontinuous thin nanoplates that selectively covered six concave facets of a Au truncated octahedron and served as etching masks in the succeeding etching process, which prevented underlying Au atoms from being oxidized. The subsequent isotropic etching proceeded radially, starting from the bare Au surface, carving the central nanocrystal in a concave manner. By controlling the etching conditions, Au@Pt hexapods were successfully fabricated, wherein the core Au domain is connected to six protruding arms, which hold Pt nanoplates at the ends. Due to their morphology, Au@Pt hexapods feature distinctive optical properties in the near-infrared region, as a proof of concept, allowing for surface-enhanced Raman spectroscopy (SERS)-based monitoring of in situ CO electrooxidation. We further extended our synthetic library by tailoring the size of the Pt nanoplates and neck widths of Au branches, demonstrating the validity of selective blocking and etching-based colloidal synthesis.

Tin-based perovskite films fabricated by chemical vapor deposition for photodetector application

Tin-based perovskite materials have shown great potential applications in environment-friendly optoelectronic devices. However, it is difficult to control the film growth process by solution method due to the rapid formation speed of the film. In this work, tin-based perovskite (FASnI3) films were prepared by chemical vapor deposition method. The film is mainly composed of thin nanoplates when the deposition temperature is 600 °C. The film shows good antioxidant properties by comparing the ratio between Sn4+ and Sn2+. Time-resolved fluorescence imaging measurements clearly reveal the fluorescence lifetime inhomogeneity in the film. The photodetectors based on tin-based perovskite films show good photo response properties, with a switching ratio of 808. This work provides new opportunities for non-lead perovskite thin film preparation and optoelectronic application.

Assessment of dynamic instability of thin nanoplates considering size and surface energy effects

The stated goal of this study is to comprehensively understand the dynamic instability characteristics of thin nanoplate structures, taking into account the combined effects of both size and surface energy. To achieve this, we present a computational approach based on the non-classical Kirchhoff plate theory within the framework of NURBS-based isogeometric analysis (IGA). The modified couple stress theory, which includes one material length scale parameter, is implemented to adequately account for the size-dependent effect. Additionally, the Gurtin–Murdoch surface elasticity is effectively utilized to assess the influence of surface energy. For the first time, we explore the dynamic instability regions of thin nanoplates, accounting for both size and surface energy effects simultaneously. To obtain solutions from the Mathieu-Hill equations, the Bolotin method is applied in this research. A number of numerical investigations on square, circular and annular thin nanoplate models under periodic in-plane compressive loads are conducted to assess the influence of several crucial input factors on the regions of dynamic instability. The present outcomes reveal that both size and surface energy effects have a remarkable influence on the dynamic instability characteristics of the nanoplates. Accordingly, these effects contribute to an enhancement in structural rigidity at the small-scale level. Furthermore, we explore that in the case of ultra-thin nanoplates, the influence of surface energy becomes dominant. The obtained findings provide valuable insights into the behavior of thin nanoplates under dynamic in-plane loading conditions as well as can contribute to the design of more robust engineering structures.

Quantification of strain and its impact on the phase stabilization of all-inorganic cesium lead iodide perovskites

•CsPbI3 nanoplates are epitaxially grown on muscovite mica single-crystal substrates •Lattice strain is present and found to increase with decreasing nanoplate thickness •The strained epitaxy enhances the metastable perovskite high-T phase stability The high-temperature perovskite γ-phase of CsPbI3 readily undergoes phase transition at ambient conditions to a low-temperature non-perovskite δ-phase with a poorer optoelectronic performance, thus hindering commercialization of these materials in photovoltaics. Here, we present the epitaxial growth of CsPbI3 nanoplates on muscovite mica single-crystal substrates and demonstrate that the high-temperature phase stability of these nanoplates is enhanced by a strained interface. Strain is measured as a function of nanoplate thickness on a single-particle level through spatially resolved structural and optical characterizations and is found to increase with decreasing thickness. From quantitatively tracking the CsPbI3 phase transition for thin (<400 nm) and thick (>400 nm) nanoplates, we observe a larger fraction of thin nanoplates still maintaining their high-temperature phase after 1 month compared with their thick counterparts. These findings establish a relationship between strain and phase transition kinetics, which is critical for rational design of stable perovskite-based optoelectronic devices. The high-temperature perovskite γ-phase of CsPbI3 readily undergoes phase transition at ambient conditions to a low-temperature non-perovskite δ-phase with a poorer optoelectronic performance, thus hindering commercialization of these materials in photovoltaics. Here, we present the epitaxial growth of CsPbI3 nanoplates on muscovite mica single-crystal substrates and demonstrate that the high-temperature phase stability of these nanoplates is enhanced by a strained interface. Strain is measured as a function of nanoplate thickness on a single-particle level through spatially resolved structural and optical characterizations and is found to increase with decreasing thickness. From quantitatively tracking the CsPbI3 phase transition for thin (<400 nm) and thick (>400 nm) nanoplates, we observe a larger fraction of thin nanoplates still maintaining their high-temperature phase after 1 month compared with their thick counterparts. These findings establish a relationship between strain and phase transition kinetics, which is critical for rational design of stable perovskite-based optoelectronic devices.

Seed-Mediated Synthesis of Thin Gold Nanoplates with Tunable Edge Lengths and Optical Properties

Thin Au nanoplates show intriguing localized surface plasmon resonance (LSPR) properties with potential applications in various fields. The conventional synthesis of Au nanoplates usually involves the formation of spherical nanoparticles or produces nanoplates with large thicknesses. Herein, we demonstrate a synthesis of uniform thin Au nanoplates by using Au-Ag alloy nanoframes obtained by the galvanic replacement of Ag nanoplates with HAuCl4 as the seeds and a sulfite (SO32-) as a ligand. The SO32- ligand not only complexes with the Au salt for the controlled reduction kinetics but also strongly adsorbs on Au {111} facets for effectively constraining the crystal growth on both basal sides of the Au nanoplates for controlled shape and reduced thicknesses. This seed-mediated synthesis affords Au nanoplates with a thickness of only 7.5 nm, although the thickness increases with the edge length. The edge length can be customizable in a range of 48-167 nm, leading to tunable LSPR bands in the range of 600-1000 nm. These thin Au nanoplates are applicable not only to surface-enhanced Raman spectroscopy with enhanced sensitivity and reliability but also to a broader range of LSPR-based applications.

Two-step GISAXS characterization of NiSi2 nanoplates and Ni nanocrystals embedded in a silicon wafer covered with a silica thin film

Here, an experimental grazing-incidence small-angle X-ray scattering (GISAXS) study of the nanostructure of a sample composed of a Si(001) wafer covered by a Ni-doped SiO2 thin film and thermally treated at high temperature is described. Previous studies indicated that this type of composite contains Ni nanocrystals mainly inside the thin film and NiSi2 nanoplates buried in the Si wafer. To achieve accurate determinations of low-resolution structural parameters of the nanoparticles derived from the experimental results (shape, volume and size), two GISAXS patterns were recorded. The first pattern was produced by the Si wafer covered by a nanoporous Ni-doped SiO2 thin film and the second pattern was recorded after removal of the SiO2 thin film by chemical etching. By using the procedure of best fitting of a modeled isotropic GISAXS intensity to a set of 1D GISAXS patterns recorded before thin-film removal, the average radius and radius dispersion of a size polydisperse set of spherical Ni nanocrystals were determined. The GISAXS pattern recorded after removal of the SiO2 thin film was almost completely due to the scattering intensity produced by oriented NiSi2 nanoplates located inside the Si wafer. By fitting a theoretical function for the X-ray scattering intensity produced by oriented nanoplates to a set of experimental 1D GISAXS patterns, the maximum diameters and average thickness of the hexagonal NiSi2 nanoplates were determined. The GISAXS intensity pattern produced by the sample after thin-film removal is essentially anisotropic (with only a weak isotropic contribution from Ni nanocrystals), thus allowing for precise quantitative determinations of the relevant sizes of the NiSi2 nanoplates.

Constructing thin BiOCl nanoplates for highly efficient photocatalytic peroxymonosulfate activation: In-depth understanding of the activation process

Photocatalytic peroxymonosulfate (PMS) activation on semiconductors is attractive for remediation of wastewaters containing refractory organic pollutants because of the synergies between photocatalysis and PMS activation. However, the PMS activation route and the main reactive species are unclear and seek of highly active and stable catalysts is desirable. In this work, for the first time, BiOCl semiconductors with different morphologies are utilized for photocatalytic activation of PMS under simulated solar light to degrade carbamazepine (CBZ). Thin BiOCl nanoplates synthesized in water/ethylene glycol mixed solvents exhibit superior performances with high activities, good applicability in a wide pH range and excellent stability. The addition of PMS can dramatically accelerate (2.5 times higher) the CBZ degradation rate compared with the photocatalysis on BiOCl. The possible activation routes are carefully discussed. PMS is predominantly activated by the photo-generated electrons, not the O2− and not the holes. Serving as an electron acceptor, PMS can effectively consume electrons to inhibit the recombination of electron-hole pairs, weaken the photo-etching of BiOCl and generate additional SO4−/HO to facilitate CBZ degradation. Rather than the SO4−/HO generated from PMS, O2− and holes produced from photocatalysis are the main reactive species to dominate the degradation. The main function of PMS is to improve the intrinsic photocatalytic performance of BiOCl. This work reveals the activation route of PMS and the realistic function of PMS in photocatalysis, which would be valuable for understanding the mechanism of photocatalytic PMS activation and for designing efficient catalysts.

Bright blue-emitting CsPbBr3 nanoplates for white light emitting

Perovskite nanomaterials with highly stable and bright emission were requested for white light emitting diodes (LEDs). In this paper, superior thin CsPbBr3 nanoplates (NPLs) with an average thickness of 1.9 nm were synthesized via solvothermal reactions. A bright blue-emitting peak at 455 nm with a photoluminescence (PL) quantum yield of 89 % was observed. The high PL efficiency was kept after storing for 90 days at ambient condition. This supplied an efficient approach to solve the problem of low PL efficiency and poor stability of blue-emitting perovskite nanocrystals. The thickness of CsPbBr3 NPLs was adjusted by changing preparation conditions. The PL peak wavelength of CsPbBr3 NPLs was adjusted in a region of 455–465 nm. Through dynamic anion exchange promoted cation exchange reactions, Mn ions were introduced in the lattice of CsPbBr3 NPLs to generate bright orange emitting to create dual-luminescent CsPbBr3:Mn NPLs. A white emitting sample with a color coordinate of (0.304, 0.325) was finally fabricated using bright CsPbBr3:Mn NPLs and green-emitting CsPbBr3 nanocrystals. This work broadened the application of perovskite for display and lighting.

A neural network-based approach for bending analysis of strain gradient nanoplates

Purpose of this paper is the presentation of a novel Machine Learning (ML) technique for nanoscopic study of thin nanoplates. The second-order strain gradient theory is used to derive the governing equations and account for size effects. The ML framework is based on Physics-Informed Neural Networks (PINNs), a new concept of Artificial Neural Networks (ANNs) enriched with the mathematical model of the problem. Training of PINNs is performed using a highly efficient learning algorithm, known as Extreme Learning Machine (ELM). Two applications of this ANNs-based method are illustrated: solution of the Partial Differential Equations (PDEs) modeling the flexural response of thin nanoplates (direct problem), and identification of the length scale parameter of the nanoplate mathematical model with the aid of measurement data (inverse problem). Comparison with analytical and Finite Element (FE) solutions demonstrate the accuracy and efficiency of this ML framework as meshfree solver of high-order PDEs. The stability and reliability of the present method are verified through parameter studies on hyperparameters, network architectures, data noise and training initializations. The results presented give evidence of the effectiveness and robustness of this new ML approach for solving both direct and inverse nanoplate problems.

Nonlocal vibration of functionally graded nanoplates using a layerwise theory

This work studies the size-dependent free vibration response of functionally graded (FG) nanoplates using a layerwise theory. The proposed model supposes not only a higher-order displacement field for the core but also the first-order displacement field for the two face sheets, thereby maintaining an interlaminar displacement continuity among layers. Unlike the conventional layerwise models, the number of variables is kept fixed and does not increase for an increased number of layers. This is a very important feature compared to conventional layerwise models and facilitates significantly the engineering analyses. The material properties of the FG nanoplate are graded continuously through the thickness direction in accordance with a power-law function. The Eringen’s nonlocal elasticity theory is here adopted to relax the continuum axiom required in classical continuum mechanics and hence hopeful to capture the small size effects of naturally discrete nanoplates. The equations of motion of the problem are obtained via a classical Hamilton’s principle. The present layerwise model is implemented with a computationally efficient C0- continuous isoparametric serendipity elements and applied to solve a large-scale discrete numerical problem. The robustness and reliability of the developed finite element model are demonstrated by a comparative evaluation of results against predictions from literature. The comparative studies show that the proposed finite element model is: (a) free of shear locking, (b) accurate with a fast rate convergence for both thin and thick FG nanoplates, and (c) excellent in terms of numerical stability. Moreover, a detailed parametric analysis checks for the sensitivity of the vibration response of FG nanoplates to the aspect ratio, length-to-thickness ratio, nonlocal parameter, boundary conditions, power-law index, and modes shapes. Referential results are also reported, for the first time, for natural frequencies of FGM nanoplates which will serve as benchmarks for further computational investigations.

Highly oriented NiSi2@Si thin-nanocomposite produced by solid state diffusion: Morphological and crystallographic characterization

This article describes a morphological and crystallographic multi-technique characterization of a 2D-nanocomposite consisting of highly oriented NiSi2 nanoplates endotaxially grown inside a single-crystalline Si(001) wafer close to its external surface. This nanostructured material is prepared using a novel procedure which promotes the diffusion of Ni atoms from a deposited Ni-dopped-SiO2 thin film into the volume of a Si(001) flat wafer under controlled thermodynamic conditions. High Resolution Scanning Transmission Electron Microscopy images reveal the formations of well oriented thin hexagonal nanoplates totally buried inside a Si(001) wafer and randomly oriented nearly spherical Ni nanocrystals located inside the Ni-doped SiO2 thin film and also inside a thin layer close to external surface of the Si(001) wafer. The NiSi2 nanoplates formed by endotaxial growth have their large hexagonal flat surfaces parallel to one of the four Si{111} crystallographic planes and exhibit coherent 7A-type interfaces with the host Si matrix. Additional analyses of Grazing-Incidence Small-Angle X-ray Scattering patterns - which probe a high number of nanoparticles - indicated that the average thickness and maximum diameter of NiSi2 nanoplates are 12 nm and 118 nm, respectively, and the average radius of Ni nanocrystals is 1.7 nm. The described process for obtaining 2D-NiSi2@Si nanocomposites opens new possibilities for exploiting the structural features of these materials for use in devices requiring anisotropic electrical transport properties.

Heat-Up Colloidal Synthesis of Shape-Controlled Cu-Se-S Nanostructures-Role of Precursor and Surfactant Reactivity and Performance in N2 Electroreduction.

Copper selenide-sulfide nanostructures were synthesized using metal-organic chemical routes in the presence of Cu- and Se-precursors as well as S-containing compounds. Our goal was first to examine if the initial Cu/Se 1:1 molar proportion in the starting reagents would always lead to equiatomic composition in the final product, depending on other synthesis parameters which affect the reagents reactivity. Such reaction conditions were the types of precursors, surfactants and other reagents, as well as the synthesis temperature. The use of ‘hot-injection’ processes was avoided, focusing on ‘non-injection’ ones; that is, only heat-up protocols were employed, which have the advantage of simple operation and scalability. All reagents were mixed at room temperature followed by further heating to a selected high temperature. It was found that for samples with particles of bigger size and anisotropic shape the CuSe composition was favored, whereas particles with smaller size and spherical shape possessed a Cu2−xSe phase, especially when no sulfur was present. Apart from elemental Se, Al2Se3 was used as an efficient selenium source for the first time for the acquisition of copper selenide nanostructures. The use of dodecanethiol in the presence of trioctylphosphine and elemental Se promoted the incorporation of sulfur in the materials crystal lattice, leading to Cu-Se-S compositions. A variety of techniques were used to characterize the formed nanomaterials such as XRD, TEM, HRTEM, STEM-EDX, AFM and UV-Vis-NIR. Promising results, especially for thin anisotropic nanoplates for use as electrocatalysts in nitrogen reduction reaction (NRR), were obtained.

Synthesis of CuO/rGO nanocomposites for carcinogenic Congo red photodegradation

Removal of carcinogenic Congo red from polluted water is challenging because of its chemical stability and inertness. Here, CuO microsphere assembled rGO nanosheets were successfully fabricated by a simple hydrothermal method for photocatalytic degradation of Congo red. The morphology and microstructure of the CuO/rGO nanocomposites were studied by scanning electron microscopy and X-ray diffraction. The results showed that the produced CuO has a spherical flower like structure that crystallised in the monoclinic crystal phase with a diameter of about 5 μm, combined with thin rGO nanoplates. Fourier transform infrared spectroscopy and Raman spectroscopy confirmed the existence of chemical bonds and vibrational modes of both CuO and rGO. The effect of H2O2 content on the photocatalytic characteristics of as-prepared samples was investigated. The results showed that H2O2 played a key factor in the photocatalytic efficiency. The content of 1 ml H2O2 (30%) exhibited the highest photocatalytic efficiency toward Congo red dye degradation in CuO/rGO (50 mg) under UV light radiation, where it completely removed over 95% Congo red in 100 ml of solution (20 mg L−1) after 120 min of illumination.

The role of positively charge poly-L-lysine in the formation of high yield gold nanoplates on the surface for plasmonic sensing application.

An anisotropic structure, gold (Au) nanoplates was synthesized using a two-step wet chemical seed mediated growth method (SMGM) directly on the substrate surface. Prior to the synthesis process, poly-l-lysine (PLL) as a cation polymer was used to enhance the yield of grown Au nanoplates. The electrostatic interaction of positive charged by PLL with negative charges from citrate-capped gold nanoseeds contributes to the yield increment. The percentage of PLL was varied from 0% to 10% to study the morphology of Au nanoplates in term of shape, size and surface density. 5% PLL with single layer treatment produce a variety of plate shapes such as hexagonal, flat rod and triangular obtained over the whole substrate surface with the estimated maximum yield up to ca. 48%. The high yield of Au nanoplates exhibit dual plasmonic peaks response that are associated with transverse and longitudinal localized surface plasmon resonance (TSPR and LSPR). Then, the PLL treatment process was repeated twice resulting the increment of Au nanoplates products to ca. 60%. The thin film Au nanoplates was further used as sensing materials in plasmonic sensor for detection of boric acid. The anisotropic Au nanoplates have four sensing parameters being monitored when the medium changes, which are peak position (wavelength shift), intensity of TSPR and LSPR, and the changes on sensing responses. The sensor responses are based on the interaction of light with dielectric properties from surrounding medium. The resonance effect produces by a collection of electron vibration on the Au nanoparticles surface after hit by light are captured as the responses. As a conclusion, it was found that the PLL treatment is capable to promote high yield of Au nanoplates. Moreover, the high yield of the Au nanoplates is an indication as excellent candidate for sensing material in plasmonic sensor.

Optimization of Nanostructured Copper Sulfide to Achieve Enhanced Enzyme-Mimic Activities for Improving Anti-Infection Performance

Advanced antibacterial methods are urgently needed to deal with possible infectious diseases. As promising alternatives to antibiotics, enzyme-mimic nanocatalysts face bottlenecks of low activities and indistinct catalytic mechanisms, which seriously restrict their development for anti-infection treatment. Herein, metastable copper sulfide (Cu2-xS) nanozymes with diversiform sizes and compositions were selected to adjust the electronic structure for enhancing enzyme-mimic activities. The as-synthesized large and thin nanoplates (L/TN nanoplates), with the stoichiometric ratio of Cu1.25S, were proven to possess the optimal peroxidase (POD)-mimic activity. Using quantum mechanics, it was theoretically revealed that the sulfur vacancies could alter the electronic structure of copper active sites and thus reduce the reaction energy barrier of H2O2 to·OH to promote the POD-mimic performance. Moreover, through enhanced enzyme-mimic activities, L/TN nanoplates achieved efficient depletion of glutathione and ascorbic acid for improving antibacterial performances. Further, synergizing with the NIR irradiation, the satisfactory destruction capability for bacteria and biofilm was achieved for L/TN nanoplates under an inflammatory level of hydrogen peroxide (50 μM). Altogether, this work provides a deeper understanding of geometrical and electronic properties-dependent antibacterial performance, and paves the way toward precise compositions and structures engineering of nanozymes.

Weak Localization and Weak Anti-Localization in Ultra Thin Sb2Te3 Nanoplates

Weak Localization and Weak Anti-Localization in Ultra Thin Sb2Te3 Nanoplates

Structural Evolution of MOF-Derived RuCo, A General Catalyst for the Guerbet Reaction.

Guerbet alcohols, a class of β-branched terminal alcohols, find widespread application because of their low melting points and excellent fluidity. Because of the limitations in the activity and selectivity of existing Guerbet catalysts, Guerbet alcohols are not currently produced via the Guerbet reaction but via hydroformylation of oil-derived alkenes followed by aldol condensation. In pursuit of a one-step synthesis of Guerbet alcohols from simple linear alcohol precursors, we show that MOF-derived RuCo alloys achieve over a million turnovers in the Guerbet reaction of 1-propanol, 1-butanol, and 1-pentanol. The active catalyst is formed in situ from ruthenium-impregnated metal-organic framework MFU-1. XPS and XAS studies indicate that the precatalyst is composed of Ru precursor trapped inside the MOF pores with no change in the oxidation state or coordination environment of Ru upon MOF incorporation. The significantly higher reactivity of Ru-impregnated MOF versus a physical mixture of Ru precursor and MOF suggests that the MOF plays an important role in templating the formation of the active catalyst and/or its stabilization. XPS reveals partial reduction of both ruthenium and MOF-derived cobalt under the Guerbet reaction conditions, and TEM/EDX imaging shows that Ru is decorated on the edges of dense nanoparticles, as well as thin nanoplates of CoOx. The use of ethanol rather than higher alcohols as a substrate results in lower turnover frequencies, and RuCo recovered from ethanol upgrading lacks nanostructures with plate-like morphology and does not exhibit Ru-enrichment on the surface and edge sites. Notably, 1H and 31P NMR studies show that through use of K3PO4 as a base promoter in the RuCo-catalyzed alcohol upgrading, the formation of carboxylate salts, a common side product in the Guerbet reaction, was effectively eliminated.

Ag nanoparticles modified crumpled borophene supported Co3O4 catalyst showing superior oxygen evolution reaction (OER) performance

Herein, we report borophene decorated with Ag nanoparticles (Ag@B) as a support, which shows greatly enhanced oxygen-evolution-reaction (OER) performance for Co3O4 catalysts. The excellent OER performance of Co3O4-Ag@B is attributed into two main reasons. First, the conductive Ag-nanoparticles on borophene facilitate the growth of thin Co3O4 nanoplates based on an epitaxy model that greatly enhances the population of Co3O4 catalyst sites on the surface. In the meantime, Ag nanoparticles increase the electrical conductivity of the support, facilitating electrons-transfer from CoⅢ atoms to form catalytically-active CoⅣ sites. Second, the B atoms strongly interact with Co and O atoms on the Co3O4 nanoplates, greatly reducing the energy barrier of OER rate-determining procedure and increasing their stability on borophene supports. The Co3O4-Ag@B requires an overpotential of 270 mV and exhibits a Tafel-slope of 62 mV dec−1 to deliver an oxygen-evolving current-density of 10 mA cm−2, indicating 60 mV lower overpotential and 27 mV dec−1 lower Tafel-slop value than the Co3O4-Ag@rGO catalysts.

Correction to: Selective ethanol gas sensing performance of flower-shaped CuO composed of thin nanoplates

Correction to: Selective ethanol gas sensing performance of flower-shaped CuO composed of thin nanoplates