Showing papers on "Diamond published in 2021"
TL;DR: In this article, a review of the types, synthesis, characterization method, properties, applications, and toxic effect of carbon nanotubes (CNTs) is presented, and the purification and sorting process of CNTs for applications are also presented in summarized form.
Abstract: A foremost and inimitable invention in the part of nanotechnology is carbon nanotubes (CNT). Crystal structures are nearly analogous to the nuclear atomic arrangement of graphite and diamond. While graphite belongs to sp2 – bonded carbon whereas diamond is owned by sp3– hybridized carbon. The evolution of CNTs began in 1991. CNTs contain some important traits such as lightweight, small in size, good strength, and high conductivity. CNT make useful in various materials like polymers, ceramics, and metallic surfaces. From an application perspective of CNTs, it can use in the nanotechnology field, nanomedicine, transistor, vacuum electronic devices, biosensors, membranes, and capacitors. Various types of synthesis techniques for CNTs are the arc-discharge method, laser ablation method; chemical vapor deposition method, vapor-phase growth, flame synthesis method, and plasma-assisted growth of CNTs. CNTs have inimitable kind of properties like mechanical, electrical, and optical. These properties can even be measured on single nanotubes. For commercial application, large quantities of purified nanotubes are needed. This present review covers the types, synthesis, characterization method, properties, applications, and toxic effect. The purification and sorting process of CNTs for applications are also presented in a summarized form.
174 citations
TL;DR: Diamond with an ultra-wide bandgap shows intrinsic performance that is extraordinarily superior to those of the currently available wide-bandgap semiconductors for deep-ultraviolet (DUV) photoelectronic applications as discussed by the authors.
Abstract: Diamond with an ultra-wide bandgap shows intrinsic performance that is extraordinarily superior to those of the currently available wide-bandgap semiconductors for deep-ultraviolet (DUV) photoelect...
103 citations
TL;DR: In this paper, the use of silicon carbide (SiC) for direct detection of sub-GeV dark matter was proposed, which has properties similar to both silicon and diamond but has two key advantages: (i) it is a polar semiconductor which allows sensitivity to a broader range of dark matter candidates; and (ii) it exists in many stable polymorphs with varying physical properties and hence has tunable sensitivity to various dark matter models.
Abstract: We propose the use of silicon carbide (SiC) for direct detection of sub-GeV dark matter. SiC has properties similar to both silicon and diamond but has two key advantages: (i) it is a polar semiconductor which allows sensitivity to a broader range of dark matter candidates; and (ii) it exists in many stable polymorphs with varying physical properties and hence has tunable sensitivity to various dark matter models. We show that SiC is an excellent target to search for electron, nuclear and phonon excitations from scattering of dark matter down to 10 keV in mass, as well as for absorption processes of dark matter down to 10 meV in mass. Combined with its widespread use as an alternative to silicon in other detector technologies and its availability compared to diamond, our results demonstrate that SiC holds much promise as a novel dark matter detector.
70 citations
TL;DR: In this paper, a single-crystalline diamond bridge structure with 1 micrometer length by 100 nanometer width and uniform elastic strains under uniaxial tensile loading along the [100, [101, and [111] directions at room temperature was constructed.
Abstract: Diamond is not only the hardest material in nature, but is also an extreme electronic material with an ultrawide bandgap, exceptional carrier mobilities, and thermal conductivity. Straining diamond can push such extreme figures of merit for device applications. We microfabricated single-crystalline diamond bridge structures with ~1 micrometer length by ~100 nanometer width and achieved sample-wide uniform elastic strains under uniaxial tensile loading along the [100], [101], and [111] directions at room temperature. We also demonstrated deep elastic straining of diamond microbridge arrays. The ultralarge, highly controllable elastic strains can fundamentally change the bulk band structures of diamond, including a substantial calculated bandgap reduction as much as ~2 electron volts. Our demonstration highlights the immense application potential of deep elastic strain engineering for photonics, electronics, and quantum information technologies.
63 citations
TL;DR: A review of surface transfer doping of diamond can be found in this paper, where the authors present a history and current outlook of this highly exploitable attribute, as well as a review of the current state-of-the-art.
59 citations
TL;DR: In this article, the authors successfully synthesized millimetre-sized samples of transparent, nearly pure sp3 amorphous carbon by heating fullerenes at pressures close to the cage collapse boundary.
Abstract: Amorphous materials inherit short- and medium-range order from the corresponding crystal and thus preserve some of its properties while still exhibiting novel properties1,2. Due to its important applications in technology, amorphous carbon with sp2 or mixed sp2–sp3 hybridization has been explored and prepared3,4, but synthesis of bulk amorphous carbon with sp3 concentration close to 100% remains a challenge. Such materials inherit the short-/medium-range order of diamond and should also inherit its superior properties5. Here, we successfully synthesized millimetre-sized samples—with volumes 103–104 times as large as produced in earlier studies—of transparent, nearly pure sp3 amorphous carbon by heating fullerenes at pressures close to the cage collapse boundary. The material synthesized consists of many randomly oriented clusters with diamond-like short-/medium-range order and possesses the highest hardness (101.9 ± 2.3 GPa), elastic modulus (1,182 ± 40 GPa) and thermal conductivity (26.0 ± 1.3 W m−1 K−1) observed in any known amorphous material. It also exhibits optical bandgaps tunable from 1.85 eV to 2.79 eV. These discoveries contribute to our knowledge about advanced amorphous materials and the synthesis of bulk amorphous materials by high-pressure and high-temperature techniques and may enable new applications for amorphous solids. Preparing amorphous phases of carbon with mostly sp3 bonding in bulk is challenging, but macroscopic samples that are nearly pure sp3 are synthesized here by heating fullerenes at high pressure.
59 citations
TL;DR: In this article, the authors used ramp-shaped laser pulses and simultaneously measured nanosecond-duration time-resolved X-ray diffraction to find that solid carbon retains the diamond structure far beyond its regime of predicted stability.
Abstract: Carbon is the fourth-most prevalent element in the Universe and essential for all known life. In the elemental form it is found in multiple allotropes, including graphite, diamond and fullerenes, and it has long been predicted that even more structures can exist at pressures greater than those at Earth’s core1–3. Several phases have been predicted to exist in the multi-terapascal regime, which is important for accurate modelling of the interiors of carbon-rich exoplanets4,5. By compressing solid carbon to 2 terapascals (20 million atmospheres; more than five times the pressure at Earth’s core) using ramp-shaped laser pulses and simultaneously measuring nanosecond-duration time-resolved X-ray diffraction, we found that solid carbon retains the diamond structure far beyond its regime of predicted stability. The results confirm predictions that the strength of the tetrahedral molecular orbital bonds in diamond persists under enormous pressure, resulting in large energy barriers that hinder conversion to more-stable high-pressure allotropes1,2, just as graphite formation from metastable diamond is kinetically hindered at atmospheric pressure. This work nearly doubles the highest pressure at which X-ray diffraction has been recorded on any material. X-ray diffraction measurements of solid carbon compressed to pressures of about two terapascals (approximately twenty million atmospheres) find that carbon retains a diamond structure even under these extreme conditions.
58 citations
TL;DR: In this paper, the authors proposed a novel modification technique to immobilize nanoparticles by the nanopores on a boron-doped diamond surface and improved the stability of nanoparticles layer by the anchoring effect.
56 citations
TL;DR: In this article, physical properties and structural transformations observed in high pressure experiments, at and above room temperature, are reviewed for a large number of solid carbon allotropes including bulk carbon such as graphite, diamond, glass-like and amorphous carbon, two-dimensional graphene, and molecular carbon in the form of one-dimensional carbon nanotubes and zero-dimensional fullerenes.
55 citations
TL;DR: A review of diamane research can be found in this paper, where the authors discuss the progress made so far and outline the prospects for this field, at the crossroads of the timeless diamond and decade-old graphene.
Abstract: Two-dimensional diamond, or diamane, is an ultrathin film with unique physical properties that combine the record values of the bulk crystal with the exciting features caused by the nanoscale nature. At the current stage of research, the diamane properties are mostly studied theoretically, and the main experimental efforts are directed at its synthesis. The latter is the trickiest problem since traditional methods involving the application of high pressure are not fully suitable due to the influence of surface effects. For diamane research, this poses a number of challenges, whose description is the main purpose and scope of this review. The paper also discusses the progress made so far and outlines the prospects for this field, at the crossroads of the timeless diamond and decade-old graphene.
52 citations
TL;DR: In this article, the authors summarized the latest developments of nitrogen-vacancy (NV) based quantum sensing with a focus on biomedical applications, including measurements of magnetic biomaterials, intracellular temperature, localized physiological species, action potentials, and electronic and nuclear spins.
Abstract: The long-dreamed-of capability of monitoring the molecular machinery in living systems has not been realized yet, mainly due to the technical limitations of current sensing technologies. However, recently emerging quantum sensors are showing great promise for molecular detection and imaging. One of such sensing qubits is the nitrogen-vacancy (NV) center, a photoluminescent impurity in a diamond lattice with unique room-temperature optical and spin properties. This atomic-sized quantum emitter has the ability to quantitatively measure nanoscale electromagnetic fields via optical means at ambient conditions. Moreover, the unlimited photostability of NV centers, combined with the excellent diamond biocompatibility and the possibility of diamond nanoparticles internalization into the living cells, makes NV-based sensors one of the most promising and versatile platforms for various life-science applications. In this review, we will summarize the latest developments of NV-based quantum sensing with a focus on biomedical applications, including measurements of magnetic biomaterials, intracellular temperature, localized physiological species, action potentials, and electronic and nuclear spins. We will also outline the main unresolved challenges and provide future perspectives of many promising aspects of NV-based bio-sensing.
TL;DR: In this article, the difficulty of diamond film development and production, introduction of important stepping stones for thin diamond synthesis, and summarization of the main nucleation procedures for diamond film synthesis are elucidated.
Abstract: Diamond is a highly attractive material for ample applications in material science, engineering, chemistry, and biology because of its favorable properties. The advent of conductive diamond coatings and the steady demand for miniaturization in a plethora of economic and scientific fields resulted in the impetus for interdisciplinary research to develop intricate deposition techniques for thin (≤1000 nm) and ultra-thin (≤100 nm) diamond films on non-diamond substrates. By virtue of the lowered thickness, diamond coatings feature high optical transparency in UV-IR range. Combined with their semi-conductivity and mechanical robustness, they are promising candidates for solar cells, optical devices, transparent electrodes, and photochemical applications. In this review, the difficulty of (ultra-thin) diamond film development and production, introduction of important stepping stones for thin diamond synthesis, and summarization of the main nucleation procedures for diamond film synthesis are elucidated. Thereafter, applications of thin diamond coatings are highlighted with a focus on applications relying on ultrathin diamond coatings, and the excellent properties of the diamond exploited in said applications are discussed, thus guiding the reader and enabling the reader to quickly get acquainted with the research field of ultrathin diamond coatings.
TL;DR: In this article, the physical properties of a carbon orthorhombic allotrope (namely, the oP8 carbon) were studied by means of density functional theory, and its structural properties, mechanical anisotropy properties, electronic properties and mechanical properties were also predicted.
05 Jan 2021
TL;DR: In this paper, the same authors investigated the effect of parasitic defects on the achievable concentration of nitrogen-vacancy (NV) in nitrogen-doped diamond and found that the concentration of NV- ([NV-]) is influenced by the as-grown properties.
Abstract: Ensembles of nitrogen-vacancy (NV) centres in diamond are a leading platform for practical quantum sensors. Reproducible and scalable fabrication of NV-ensembles with desired properties is crucial, as is an understanding of how those properties influence performance. This work addresses these issues by characterising nitrogen-doped diamond produced by the chemical vapour deposition (CVD) method across a range of synthesis conditions. This is shown to produce material with widely differing absorption characteristics, which is linked to the level of parasitic defects other than substitutional nitrogen (NS) and NV. In such material, the achievable concentration of NV- ([NV-]) is found to be influenced by the as-grown properties. At the 10-20 ppm level for [NS], the production of CVD-grown material with strain levels sufficient not to limit achievable device sensitivity is demonstrated and a favourable product of [NV-] and T2* is obtained. Additionally, reproducible properties over a batch of 23 samples from a single synthesis run are achieved, which appears promising for the scalability efforts underway in this area of research.
TL;DR: A paracrystalline diamond was reported in this article, consisting of sub-nanometre-sized diamond structures that possess a well-defined crystalline medium-range order up to a few atomic shells.
Abstract: Solids in nature can be generally classified into crystalline and non-crystalline states1–7, depending on whether long-range lattice periodicity is present in the material. The differentiation of the two states, however, could face fundamental challenges if the degree of long-range order in crystals is significantly reduced. Here we report a paracrystalline state of diamond that is distinct from either crystalline or amorphous diamond8–10. The paracrystalline diamond reported in this work, consisting of sub-nanometre-sized paracrystallites that possess a well-defined crystalline medium-range order up to a few atomic shells4,5,11–13, was synthesized in high-pressure high-temperature conditions (for example, 30 GPa and 1,600 K) employing face-centred cubic C60 as a precursor. The structural characteristics of the paracrystalline diamond were identified through a combination of X-ray diffraction, high-resolution transmission microscopy and advanced molecular dynamics simulation. The formation of paracrystalline diamond is a result of densely distributed nucleation sites developed in compressed C60 as well as pronounced second-nearest-neighbour short-range order in amorphous diamond due to strong sp3 bonding. The discovery of paracrystalline diamond adds an unusual diamond form to the enriched carbon family14–16, which exhibits distinguishing physical properties and can be furthered exploited to develop new materials. Furthermore, this work reveals the missing link in the length scale between amorphous and crystalline states across the structural landscape, having profound implications for recognizing complex structures arising from amorphous materials. A study describes the synthesis, structural characterization and formation mechanism of a paracrystalline state of diamond, adding an unusual form of diamond to the family of carbon-based materials.
TL;DR: In this article, a method to make liquid metal composites by vigorously mixing gallium (Ga) with non-metallic particles of graphene oxide (G-O), graphite, diamond, and silicon carbide that display either paste or putty-like behavior depending on the volume fraction is described.
Abstract: We report a versatile method to make liquid metal composites by vigorously mixing gallium (Ga) with non-metallic particles of graphene oxide (G-O), graphite, diamond, and silicon carbide that display either paste or putty-like behavior depending on the volume fraction. Unlike Ga, the putty-like mixtures can be kneaded and rolled on any surface without leaving residue. By changing temperature, these materials can be stiffened, softened, and, for the G-O-containing composite, even made porous. The gallium putty (GalP) containing reduced G-O (rG-O) has excellent electromagnetic interference shielding effectiveness. GalP with diamond filler has excellent thermal conductivity and heat transfer superior to a commercial liquid metal-based thermal paste. Composites can also be formed from eutectic alloys of Ga including Ga-In (EGaIn), Ga-Sn (EGaSn), and Ga-In-Sn (EGaInSn or Galinstan). The versatility of our approach allows a variety of fillers to be incorporated in liquid metals, potentially allowing filler-specific "fit for purpose" materials.
TL;DR: A review of the diamond nucleation/seeding techniques can be found in this article, where the authors discuss the advantages and disadvantages of individual techniques and compare them with other techniques.
Abstract: Diamond thin films are known to have properties similar to bulk diamond and have applications in both industry and fundamental studies in academia. The high surface energy of diamond makes it extremely difficult to grow diamond films on foreign substrates. Hence, to grow diamond films on non-diamond substrates, a nucleation step is needed. In this review various techniques used for diamond nucleation/seeding will be discussed. At present electrostatic seeding by diamond nanoparticles is the most commonly used seeding technique for nanocrystalline growth. In this technique the substrate is dipped in a nanodiamond solution to form a mono layer of diamond seeds. These seeds when exposed to appropriate conditions grow to form diamond layers. This technique is suitable for most substrates. For heteroepitaxial growth, bias enhanced nucleation is the primary technique. In this technique the substrate is biased to form diamond nuclei in the initial stages of growth. This technique can be used for any conducting flat surface. For growth on ceramics, polishing by diamond grit or electrostatic seeding can be used. Polishing the ceramics with diamond powder leaves small diamond particles embedded in the substrate. These small particles then act as seeds for subsequent diamond growth. Apart from these techniques, chemical nucleation, interlayer driven nucleation and mixed techniques have been discussed. The advantages and disadvantages of individual techniques have also been discussed.
TL;DR: In this article, a novel carbon phase with a purely sp3-bonded network and an orthorhombic unit cell of 24 atoms, called Pmma C24, was established and the structural characteristics, elastic properties, and mechanical and electronic properties of this novel carbon structure at different pressures.
TL;DR: In this article, the first measurements of magnetic sensing from mammalian tissue with a diamond sensor using mouse muscle optogenetically activated with blue light were presented in an ordinary, unshielded lab environment and the signal can be easily recovered by digital signal processing techniques.
Abstract: The ability to perform noninvasive and non-contact measurements of electric signals produced by action potentials is essential in biomedicine. A key method to do this is to remotely sense signals by the magnetic field they induce. Existing methods for magnetic field sensing of mammalian tissue, used in techniques such as magnetoencephalography of the brain, require cryogenically cooled superconducting detectors. These have many disadvantages in terms of high cost, flexibility and limited portability as well as poor spatial and temporal resolution. In this work we demonstrate an alternative technique for detecting magnetic fields generated by the current from action potentials in living tissue using nitrogen vacancy centres in diamond. With 50 pT/
$$\sqrt{\text {Hz}}$$
sensitivity, we show the first measurements of magnetic sensing from mammalian tissue with a diamond sensor using mouse muscle optogenetically activated with blue light. We show these proof of principle measurements can be performed in an ordinary, unshielded lab environment and that the signal can be easily recovered by digital signal processing techniques. Although as yet uncompetitive with probe electrophysiology in terms of sensitivity, we demonstrate the feasibility of sensing action potentials via magnetic field in mammals using a diamond quantum sensor, as a step towards microscopic imaging of electrical activity in a biological sample using nitrogen vacancy centres in diamond.
TL;DR: In this article, the authors demonstrate high-sensitivity N-$V$-ensemble-based magnetic field measurements with low-intensity optical excitation using a diamond magnetometer, achieving a minimum detectable field of 0.3-0.7 pT in a 73-s measurement when a flux guide with a sensing dimension of 2 mm is applied.
Abstract: Nitrogen-vacancy (N-$V$) centers in diamond have developed into a powerful solid-state platform for compact quantum sensors. However, high-sensitivity measurements usually come with additional constraints on the pumping intensity of the laser and the pulse control applied. Here, we demonstrate high-sensitivity N-$V$-ensemble-based magnetic field measurements with low-intensity optical excitation. Direct current magnetometry methods such as continuous-wave optically detected magnetic resonance and continuously excited Ramsey measurements combined with lock-in detection are compared to achieve an optimization. Gradiometry is also investigated as a step towards unshielded measurements of unknown gradients. The magnetometer demonstrates a minimum detectable field of 0.3--0.7 pT in a 73-s measurement when a flux guide with a sensing dimension of 2 mm is applied, corresponding to a magnetic field sensitivity of 2.6--6 $\mathrm{pT}/\sqrt{\mathrm{Hz}}$. Combined with our previous efforts on diamond ac magnetometry, the diamond magnetometer is promising for performing wide-bandwidth magnetometry with picotesla sensitivity and a cubic-millimeter sensing volume under ambient conditions.
TL;DR: In this article, a series of filler metals and brazing methods for diamond tools are reviewed systematically, and the fracture modes and stress distribution issues are considered as the major reliability concern.
TL;DR: In this article, the authors reviewed the recent research works carried out on this topic, and this primarily includes evaluating the commonly acknowledged principles for acquiring high thermal conductivity of copper/diamond composites that are produced by different processing methods; and elaborating the interface thermal conductance problem to increase the understanding of thermal transferring mechanisms in the boundary area and provide necessary guidance for future designing composite interface structure.
Abstract: Copper/diamond composites have drawn lots of attention in the last few decades, due to its potential high thermal conductivity and promising applications in high-power electronic devices. However, the bottlenecks for their practical application are high manufacturing/machining cost and uncontrollable thermal performance affected by the interface characteristics, and the interface thermal conductance mechanisms are still unclear. In this paper, we reviewed the recent research works carried out on this topic, and this primarily includes (1) evaluating the commonly acknowledged principles for acquiring high thermal conductivity of copper/diamond composites that are produced by different processing methods; (2) addressing the factors that influence the thermal conductivity of copper/diamond composites; and (3) elaborating the interface thermal conductance problem to increase the understanding of thermal transferring mechanisms in the boundary area and provide necessary guidance for future designing the composite interface structure. The links between the composite’s interface thermal conductance and thermal conductivity, which are built quantitatively via the developed models, were also reviewed in the last part.
TL;DR: In this paper, a double-layered interface structure is formed between the copper matrix and the diamond particle in the Cu-3Cr/55Dia composite, which is composed of 160nm-thick Cr3C2 and 2.5µn-thwick Cr23C6.
TL;DR: In this paper, the authors used hard X-ray photoelectron spectroscopy (HAXPES) for the detection of deeply buried layers beyond the elastic limit, using inelastic background analysis.
TL;DR: In this paper, a comprehensive review is presented on the advances achieved in past years on fundamental and applied materials science of diamond films and engineering to integrate them into new generations of microelectromechanical system (MEMS) and nanoelectric systems (NEMS).
Abstract: A comprehensive review is presented on the advances achieved in past years on fundamental and applied materials science of diamond films and engineering to integrate them into new generations of microelectromechanical system (MEMS) and nanoelectromechanical systems (NEMS). Specifically, the review focuses on describing the fundamental science performed to develop thin film synthesis processes and the characterization of chemical, mechanical, tribological and electronic properties of microcrystalline diamond, nanocrystalline diamond and ultrananocrystalline diamond films technologies, and the research and development focused on the integration of the diamond films with other film-based materials. The review includes both theoretical and experimental work focused on optimizing the films synthesis and the resulting properties to achieve the best possible MEMS/NEMS devices performance to produce new generation of MEMS/NEMS external environmental sensors and energy generation devices, human body implantable biosensors and energy generation devices, electron field emission devices and many more MEMS/NEMS devices, to produce transformational positive impact on the way and quality of life of people worldwide.
TL;DR: In this article, the optimal conditions for fabricating a screen-printed diamond electrode for the sensitive detection of l -cysteine (Cys), a non-essential amino acid, were investigated.
TL;DR: In this paper, an overview of recent research findings on the application of femtosecond (fs) technology to micromachine diamond is discussed and detailed, with a focus on the use of fs-laser irradiation systems and their characteristics, laser interaction with various types of diamonds, processing and the subsequent post-processing of the irradiated samples and appropriate sample characterisation methods.
TL;DR: In this article, a general strategy is developed to improve the dielectric strength of thermally conductive epoxy composites using a micron-sized diamond, by preventing an interfacial charge accumulation at the inorganic fillers.
TL;DR: In this paper, high-quality heteroepitaxial diamond (Kenzan diamond®) with NO2 p-type doping and an Al2O3 passivation overlayer exhibited a high off-state breakdown voltage of −2608 V.
Abstract: Diamond metal oxide semiconductor field effect transistors (MOSFETs) on high-quality heteroepitaxial diamond (Kenzan diamond®) with NO2 p-type doping and an Al2O3 passivation overlayer exhibited a high off-state breakdown voltage of −2608 V. The 100-nm-thick Al2O3 passivation overlayer on the hole channel increased the high-voltage-handling capability of the MOSFETs by substantially suppressing the off-state drain leakage currents. The MOSFET showed a specific on-resistance of 19.74 $\text{m}\Omega \cdot $ cm2 and a maximum drain current density of −288 mA/mm, with an extremely low gate leakage current $ mA/mm. The Baliga’s Figure-Of-Merits was experimentally determined to be 344.6 MW/cm2, and the maximum DC power density was observed to be 21.0 W/mm.