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Sulphur doped graphitic carbon nitride (SGCN) was effectively prepared and comprehensively described. A straightforward synthetic process based on thermal condensation was reported for the synthesis of SGCN using thiourea as a precursor. Cyclic voltammetry (CV) and differential pulse voltammetry were used to evaluate the electrochemical performance of cortisol. SGCN sheets were used to boost the electro-catalytic activity, exhibiting very exceptional electrochemical behaviour towards cortisol. As a result, we obtained a broad linear response range of 0.1–100 μM, as well as a comparatively low detection limit (15.8 × 10−8 M). Furthermore, the fabricated SGCN/CFP electrode shows excellent selectivity in the presence of a large number of possible interfering species. SGCN comprises (C with N and S) heteroatoms, which most likely would have led to a better current response towards cortisol detection. Furthermore, the structural defects that generate additional active sites on the surface of SGCN may enhance the quick electron transfer that occurs during the oxidation of cortisol. [ABSTRACT FROM AUTHOR]

The current research focuses on the efficiency of energy recovery from non-hazardous organic wastes. It entails the generation of low-chloride refuse-derived fuel (RDF) from municipal solid waste (MSW) through moderate pyrolysis of combustible components. The moderate pyrolysis settings and composition ratio of biogenic/non-biogenic content from MSW combination (food waste, plastic waste, and paper waste) had a significant impact on the thermochemical characteristics and fuel behavior of RDF. Furthermore, pyrolysis with optimal MSW composition was studied to reduce toxic elements (chlorides, sulphides, and nitrides) and enhance the energy value in RDF by utilizing potassium-rich (waste orange peels (OP); banana peels (BP); and maize cob (MC)) and calcium-rich species (waste animal bone meal (ABM); egg shells (ES); and mussel shells (MS)) as natural additives. The results showed that increasing the pyrolysis temperature maximized the carbon concentration with reduced oxygen moieties (low O/C ratio), indicating a high energy value as the oxygenates were eliminated during moderate pyrolysis. The RDF treated at 400 °C (SF4-400) with MSW composition of 55% non-biogenic carbon and 45% biogenic carbon resulted in HHV of 29.22 MJ kg−1, the lowest ash concentration (0.96%), and a densified microstructural surface. The addition of natural maize cob additive into MSW (SF4-400-MC) yielded the maximum HHV (33.07 MJ kg−1) with considerable reductions in chlorides (71.43%), sulphides (87.50%), and insignificant nitrides content, all of which meet ASTM RDF quality criteria Grade I. [ABSTRACT FROM AUTHOR]

A paper-based membrane coated by graphitic carbon nitride (g-C3N4) is prepared via a dip-coating method and used as a separator for sodium metal batteries with merits of low cost and environment-friendliness. Introduction of g-C3N4 effectively improves the ionic conductivity and the structural stability of the separator. Compared with traditional polyethylene separators and Al2O3-coated separators, the g-C3N4-coated separators show better electrolyte wettability, thermal stability, and electrochemical stability. Therefore, Na||Na3V2(PO4)3 battery using the g-C3N4-coated separator exhibits better cycling stability and higher rate capability. These results prove that the g-C3N4-coated paper-based separator is expected to become the next generation of low-cost and high-safety separator in sodium metal batteries. [ABSTRACT FROM AUTHOR]

Highlights: The superior conductivity and unique porous electrode structure in the TiN paper enable fast charging by simultaneously providing efficient ion diffusion and electron transport. The TiN paper-based supercapacitors exhibit charging/discharging at an ultrahigh scan rate of 100 V s−1 in a wide voltage window of 1.5 V in Na2SO4 neutral electrolyte and show zero capacitance loss after 200,000 cycles. Ultrafast-charging energy storage devices are attractive for powering personal electronics and electric vehicles. Most ultrafast-charging devices are made of carbonaceous materials such as chemically converted graphene and carbon nanotubes. Yet, their relatively low electrical conductivity may restrict their performance at ultrahigh charging rate. Here, we report the fabrication of a porous titanium nitride (TiN) paper as an alternative electrode material for ultrafast-charging devices. The TiN paper shows an excellent conductivity of 3.67 × 104 S m−1, which is considerably higher than most carbon-based electrodes. The paper-like structure also contains a combination of large pores between interconnected nanobelts and mesopores within the nanobelts. This unique electrode enables fast charging by simultaneously providing efficient ion diffusion and electron transport. The supercapacitors (SCs) made of TiN paper enable charging/discharging at an ultrahigh scan rate of 100 V s−1 in a wide voltage window of 1.5 V in Na2SO4 neutral electrolyte. It has an outstanding response time with a characteristic time constant of 4 ms. Significantly, the TiN paper-based SCs also show zero capacitance loss after 200,000 cycles, which is much better than the stability performance reported for other metal nitride SCs. Furthermore, the device shows great promise in scalability. The filtration method enables good control of the thickness and mass loading of TiN electrodes and devices. [ABSTRACT FROM AUTHOR]

A simple and effective ratiometric fluorescence sensor of CdTe QDs/GCNNs for on‐site and rapid analysis of Cu2+ has been established by mixing physically CdTe QDs and graphite carbon nitride (GCNNs). Two emissions peaks of CdTe QDs at 572 nm and GCNNs at 436 nm are both excitated at 340 nm. Under a UV lamp, fluorescent of traffic yellow CdTe QDs is linearly quenched by Cu2+ (as the detection signal), while blue GCNNs remains unchanged (as the reference), resulting in a distinguishable color change gradually from pink yellow to blue. The limit of detection (LOD) of this new sensor for Cu2+ is as low as 0.47 ng mL−1 with 1.4 % RSD. The established method has been successfully applied to detection of Cu2+ in various drinks with satisfactory results. Moreover, a paper‐based sensor, which has been prepared by soaking cellulose acetate membrane in CdTe QDs/GCNNs sensor solution, has a wide semiquantitative detection range for Cu2+ (0.01 ~ 5.0 μg mL−1). It has realized successfully on‐site and rapid determination of Cu2+ in red wine without any pretreatment procedure and is of great promotion and application value in determination of Cu2+ in liquid samples. [ABSTRACT FROM AUTHOR]

An adaptable stimuli responsive system is proposed based on defective graphitic carbon nitride (d‐GCN)/polyvinyl alcohol (PVA) composite attached to different substrates. Nitrogen vacancies, introduced during synthesis via potassium doping, act as internal electron donors to enhance the photoreduction of redox dyes for quick reversible photochromism. This system can be applied as visible light responsive rewritable paper that offers high resolution for printed text, rapid activation/recoloration, multicolor functionality, and high cyclability. The defects also inhibit the d‐GCN particle growth resulting in smaller particle sizes over bulk samples, which enable the formation of transparent mechanochromic films. By altering the PVA/d‐GCN ratio in the composites, two mechanical stimuli responses are introduced by taking advantage of wrinkle and crack formation on the film surface. With a low d‐GCN concentration, mechanical scratching of the film causes the formation of surface wrinkles that alter the film transparency without damaging the film, allowing for text to be written on the surface that can be erased by moisture. With a high d‐GCN concentration, cracks developed on the surface scatter light when stretched, enabling the development of a strain dependent smart window. Both these mechanochromisms can be combined with the photochromism to develop multifunctional smart materials with widespread application. [ABSTRACT FROM AUTHOR]

The document is a contents list for the New Journal of Chemistry, a publication by The Royal Society of Chemistry and the Centre National de la Recherche Scientifique. It features a variety of articles and papers covering topics such as anti-counterfeiting printing, monitoring platinum(IV) complexes, and the removal of uranium from the kidneys. The journal also provides information on training courses and resources for professional development in chemistry. The papers offer valuable insights and advancements in the field, making it a valuable resource for researchers and professionals in chemistry. [Extracted from the article]

Abstract: A dual‐emission ratiometric fluorescent sensing film for metal ion detection is designed. This dual‐emission film is successfully prepared from chitosan, graphitic carbon nitride (g‐C3N4), and gold nanoclusters (Au NCs). Here, it is shown that the g‐C3N4 not only serves as the fluorescence emission source, but also enhances the mechanical and thermal stability of the film. Meanwhile, the Au NCs are adsorbed on the surface of chitosan film by the electrostatic interaction. The as‐prepared dual‐emission film can selectively detect Cu2+, leading to the quench of red fluorescence of Au NCs, whereas the blue fluorescence from g‐C3N4 persists. The ratio of the two fluorescence intensities depends on the Cu2+ concentration and the fluorescence color changes from orange red to yellow, cyan, and finally to blue with increasing Cu2+ concentration. Thus, the as‐prepared dual‐emission film can be worked as ratiometric sensing paper for Cu2+ detection. Furthermore, the film shows high sensitivity and selectivity, with low limit of detection (LOD) (10 ppb). It is observed that this novel gold‐cluster‐based dual‐emission ratiometric fluorescent sensing paper is an easy and convenient way for detecting metal ions. It is believed that this research work have created another avenue for the detection of metal ions in the environment. [ABSTRACT FROM AUTHOR]

Escherichia coli O157:H7 (E. coli O157:H7) is a typical foodborne pathogen that contaminates food and water, leading to lots of infectious diseases. In this study, a near-infrared-responsive photoelectrochemical (PEC) sensing platform for the ultrasensitive detection of E. coli O157:H7 was established by assembling a flexible conductive paper electrode with core-shell-structured upconversion nanophosphors (UCNPs) @SiO 2 @Ag and carbon self-doped graphitic carbon nitride (C-g-C 3 N 4). In this design, UCNPs act as a self-powered that change near infrared (NIR) excitation into visible emission, while the semiconductor material C-g-C 3 N 4 acts as the energy-conversion center to convert visible illumination to photocurrent. Importantly, silver nanoparticles (AgNPs) significantly enhance the upconversion luminescence of UCNPs and facilitate the separation and transportation of photoelectrons by the localized surface plasmon resonance effect. Using the antimicrobial peptide Magainin I as the recognition element, E. coli O157:H7 was specifically captured and determined directly for its steric hindrance effect on the photoelectrode. As a result, the photocurrent decreased linearly with the increase in E. coli O157:H7 in a wide range from 5 to 5 × 106 colony-forming units per mL (CFU/mL), and the detection limit was as low as 2 CFU/mL. Finally, the proposed NIR PEC sensor was successfully utilized for the determination of E. coli O157:H7 in contaminated pork, cabbage, and milk samples without enrichment of the bacteria in 50 min. ◆ A paper-supported NIR (980 nm) - responsive PEC sensing platform was developed ◆ AgNPs dramatically improved the UCL of UCNPs and the PEC performance of C-g-C 3 N 4 ◆ E. coli O157:H7 was concentrated and determined using the proposed NIR PEC platform ◆ A relatively low LOD of 2 CFU/mL was achieved for E. coli O157:H7 detection ◆ Due to the high sensitivity, there is no need to enrich bacteria before detection ◆ The proposed method could be used for rapid detection of E. coli O157:H7 in food [ABSTRACT FROM AUTHOR]

Flexible non-metal oxygen electrodes fabricated from phosphorus-doped graphitic carbon nitride nano-flowers directly grown on carbon-fiber paper exhibit high activity and stability in reversibly catalyzing oxygen reduction and evolution reactions, which is a result of N, P dual action, enhanced mass/charge transfer, and high active surface area. The performance is comparable to that of the state-of-the-art transition-metal, noble-metal, and non-metal catalysts. Remarkably, the flexible nature of these oxygen electrodes allows their use in folded and rolled-up forms, and directly as cathodes in Zn-air batteries, featuring low charge/discharge overpotential and long lifetime. [ABSTRACT FROM AUTHOR]

• Carbon nitride nanoparticles were synthesized from Ginkgo leaves without using surfactant. • Colorimetric assay for tetracycline using paper-based device based on fluorescent quenching. • Image of paper-based device was captured by a smartphone. • Tetracycline concentration was determined from color change of images. A novel colorimetric assay for tetracycline (TC) using a paper-based analytical device (PAD) coupled with fluorescent carbon nitride nanoparticles (CNNPs) is proposed. The fluorescent intensity of CNNPs which were prepared from Ginkgo leaves using a one-step hydrothermal approach without any surfactant was quenched in the presence of TC. The color change of the TC colorimetric PAD, which is visually observable, was captured by a smartphone. A smartphone application was then used to assess the color images by extracting the red, green, and blue (RGB) values. The TC-PAD was confirmed to exhibit a good linearity (R2 = 0.9963) in the range of 0.8–400 µM and the detection limit was calculated to be 120 nM. Additionally, the TC-PAD exhibits acceptable repeatability (RSD < 2.9%) on real samples to give a potential for practical applications. The developed CNNPs were characterized by X-ray diffraction, UV–vis spectrometry, spectrofluorometry, X-ray photoelectron spectroscopy, and elemental analysis. [ABSTRACT FROM AUTHOR]

Mesoporous carbon nitrides (MCN) were prepared by a nano-casting method using mesoporous silica as a template with different carbon and nitrogen sources like melamine only (MS-MCN), urea-formaldehyde (UF-MCN) and melamine-glyoxal (MG-MCN). These mesoporous carbon nitride materials possess nitrogen moieties which behave like a CO2-philic surface facilitating oxidation of cyclic olefins by molecular oxygen in the co-presence of CO2below supercritical conditions. The co-presence of CO2augmented the conversions of cyclic olefins at low pressures of CO2, depicting a promotional effect. Approaches towards quantification of promotional effects and insights into the promotional aspects have been studied. [ABSTRACT FROM AUTHOR]

Alkenylsuccinic Anhydride (ASA) is commonly applied as oil-in-water emulsions in papermaking industry. Herein, a particle stabilized ASA emulsion was developed for avoiding the adverse effect of surfactant, further improving the sizing performance and reducing the hydrolysis of ASA Pickering emulsions, where Laponite nanoparticles were employed as a stabilizer of the ASA Pickering emulsions after being modified with carbon nitride quantum dots. It was found that the hydrophilic Laponite particles became partially hydrophobic after being modified with CNQDs in dosage of 20–40 wt%, and thus promoted the formation of emulsions with fine and uniform droplets that resisted creaming/coalescence formation. The adsorption of the Laponite/CNQDs particles on the ASA droplet surface improved the emulsion stability, which was verified by fluorescent confocal laser scanning microscopy. Meanwhile, by using Laponite/CNQDs nanoparticles, the storage stability of ASA Pickering emulsion and its sizing performance on paper was also improved. Unlabelled Image • CNQD adsorption improved the Laponite hydrophobic property and the adsorption efficacy at the ASA-water interfaces. • The Pickering emulsion's stabilization mechanism was adequately illustrated using Laponite/CNQDs as fluorescent probes. • Different concentrations of Laponite do not induce CNQD fluorescence quenching. • Laponite/CNQDs can maintain ASA emulsion stability over extended aging periods and sustain high sizing performance [ABSTRACT FROM AUTHOR]

Norovirus is one of the leading causes of gastroenteritis, acute vomiting, intense diarrhoea, acute pain in the stomach, high fever, headaches, and body pain. Conventional methods of detection gave us very promising results but had disadvantages such as low sensitivity, cost ineffectiveness, reduced specificity and selectivity, etc. Therefore, biosensors can be a viable alternative device which can overcome all setbacks associated with the conventional method. An electrochemical sensor based on oxidized graphitic carbon nitride (Ox-g-C3N4) modified electrochemical paper-based analytical device (ePAD) was fabricated for the detection of norovirus DNA. The synthesized Ox-g-C3N4 nanosheets were characterized by field emission scanning electron microscopy (FESEM), X-ray Diffraction (XRD), UV-Vis spectroscopy and X-Ray Photoelectron Spectroscopy. The capture probe DNA (PDNA) modified electrodes were characterized by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). These two characterization techniques were also employed to find the optimal scan rate, response time and temperature of the fabricated sensor. The fabricated biosensor showed a limit of detection (LOD) of 100 fM. Furthermore, the specificity of the reported biosensor was affirmed by testing the response of capture probe DNA with oxidized graphitic carbon nitride (PDNA/Ox-g-C3N4) modified ePAD on the introduction of a non-complimentary DNA. The fabricated ePAD sensor is easy to fabricate, cost effective and specific, and requires a minimum analysis time of 5 s. [ABSTRACT FROM AUTHOR]

Graphitic carbon nitride (gCN) has shown great potential in photocatalysis. Developing suitable cocatalysts is a critical way to enhance gCN's photocatalytic performance. In this paper cobalt–nickel bimetallic phosphide (CoNiP) was used as a cocatalyst to modify gCN. A gCN/CoNiP composite was successfully prepared by a simple hydrothermal method. XRD, XPS, SEM, UV-vis DRS, and PL characterization studies showed that a Schottky junction-like structure was constructed between gCN and CoNiP, which intensified the visible light response, enhanced the charge transfer rate and prohibited the recombination of photogenerated carriers, thus significantly improving gCN photocatalytic activity. Under simulated sunlight, the removal efficiency of methylene blue (10 mg L−1) was 97.8% by 120 min of irradiation, 44.6% higher than that of gCN. The quenching experiment showed that ˙O2−, ˙OH and h+ were the main active species. Based on the above points, the possible mechanism of photocatalysis was deduced. [ABSTRACT FROM AUTHOR]

Nickel-based alloys that contain chromium are widely used in corrosion-resistant applications in industry, but they are sensitive to the environment when the passive chromium oxide layer is damaged. In Ni600 and Ni625 alloys, precipitates can deplete the surface layer of chromium oxide. To better characterize and analyze the nickel alloy surfaces and their chromium carbides, chemical etching with different etchants and electrolytic etching were applied to sample surfaces. This paper revealed their efficacy in etching various carbides within the nickel alloys, and orange phases ranging from 2 to 20 μm in optical micrographs were identified as titanium-containing compounds. Carbides located on the grain boundaries were determined to be Cr23C6 and were surrounded by chromium-depleted zones. The findings and figures in this paper provide a more intuitive reference for future analysis of carbides and titanium nitrides, enhancing the understanding of their impact on the corrosion resistance of these alloys, which will not only contribute to the material science field but also aid in developing the Ni-based alloys for industrial applications. [ABSTRACT FROM AUTHOR]

This paper reports on the photodegradation of the Rh 6G dye using a g-C3N4 (g-CN) nanosheet photocatalyst under UV light irradiation. The g-C3N4 nanosheets were synthesized using a simple pyrolysis method at 450 °C for 3 h at a heating rate of 2 °C min−1. Their structural phase, functional groups, surface area, optical properties, elemental composition, and morphology were investigated via XRD, BET, UV-vis, photoluminescence spectroscopy, X-ray photoelectron spectroscopy, energy dispersive spectroscopy, and SEM microscopy. The tri-s-triazine structure of g-C3N4 was confirmed and the crystal size was calculated to be 5 nm. g-C3N4 displayed a nanosheet morphology with a BET surface area of 8 m2 g−1. C–N stretching and s-triazine units were observed in the FTIR spectrum. The photoluminescence (PL) emission maximum at 432 nm provided band edge emission related to a band gap of 2.9 eV, and the PL lifetime was 7.6 ns, which is reasonably high for photocatalytic application. Through the C1s XPS spectrum, sp2-hybridized carbon linkages of N–C＝N in the aromatic skeleton rings, such as triazine or heptazine rings, of g-C3N4 were found. The photocatalytic characteristics of g-C3N4 were studied with the Rh-6G dye using UV light illumination. Initially, the Rh-6G dye concentration and catalyst (g-C3N4) loading were optimized for the best dye degradation at 0.01 mmol and 50 mg, respectively. The maximum efficiency of g-C3N4 was 99.6% degradation of the Rh-6G dye in 300 minutes. Lower charge-transfer resistance was found to be the reason for the enhanced photodegradation activity. The most dominant reactive species that participated in the light-activated reaction were superoxide radicals. The influence of pH on photodegradation was studied and the photocatalyst was found to perform better in an acidic pH range. In addition, g-C3N4 was structurally stable, highly recyclable, and, therefore, could be reused in many cycles of photocatalysis. [ABSTRACT FROM AUTHOR]

Graphitic carbon nitride (g‐C3N4) is a highly recognized two‐dimensional semiconductor material known for its exceptional chemical and physical stability, environmental friendliness, and pollution‐free advantages. These remarkable properties have sparked extensive research in the field of energy storage. This review paper presents the latest advances in the utilization of g‐C3N4 in various energy storage technologies, including lithium‐ion batteries, lithium‐sulfur batteries, sodium‐ion batteries, potassium‐ion batteries, and supercapacitors. One of the key strengths of g‐C3N4 lies in its simple preparation process along with the ease of optimizing its material structure. It possesses abundant amino and Lewis basic groups, as well as a high density of nitrogen, enabling efficient charge transfer and electrolyte solution penetration. Moreover, the graphite‐like layered structure and the presence of large π bonds in g‐C3N4 contribute to its versatility in preparing multifunctional materials with different dimensions, element and group doping, and conjugated systems. These characteristics open up possibilities for expanding its application in energy storage devices. This article comprehensively reviews the research progress on g‐C3N4 in energy storage and highlights its potential for future applications in this field. By exploring the advantages and unique features of g‐C3N4, this paper provides valuable insights into harnessing the full potential of this material for energy storage applications. [ABSTRACT FROM AUTHOR]

Within the framework of the macroscopic dielectric continuum model, the dispersive spectra of polar optical phonon modes of III-nitride based nanostructures with different inner and outer dielectric media are investigated in this paper. The dielectric and quantum size effects on the dispersive frequencies of phonon modes are focused and emphasized. In the case of GaN quantum rings (QRs), we found that the dielectric constant of the inner/outer medium could significantly influence the dispersive spectra of the surface optical (SO) phonon mode as the high/low-frequency SO phonon modes are mainly localized at the inner/outer surface of QRs, respectively. Moreover, such effects associated with different crystallographic structures of GaN, i.e., the wurtzite (WZ) and zinc blende (ZB) crystal structures, are also studied in detail, showing the different degenerating behavior and electron–phonon coupling strength. The results obtained in this study provide a beneficial opportunity to independently adjust dispersive spectra of the two branches of SO modes in GaN nanostructures; thus, it could be used to design and develop phonon-based detectors and sensors. [ABSTRACT FROM AUTHOR]

Three dimensional Not-And (3D NAND) flash memory devices are scaling in the vertical direction to more than 200 oxide/sacrificial wordline nitride layers to further increase storage capacity and enhance energy efficiency. The accurate measurement of the thicknesses of these layers is critical to controlling stress-induced wafer warping and pattern distortion. While traditional optical metrology in the UV-vis-NIR range offers a non-destructive inline solution for high volume manufacturing, we demonstrate in this paper, that mid-IR metrology has advantages in de-correlating oxide and nitride thicknesses owing to their unique absorption signatures. Furthermore, because of the depths sensitivity of oxide and nitride absorptions, the simulated measurement results show the ability to differentiate thickness variations in the vertical zones. Good blind test results were obtained with a machine learning model trained on pseudo-references and pseudo spectra with added skew. [ABSTRACT FROM AUTHOR]

Group-III nitrides have transformed solid-state lighting and are strategically positioned to revolutionize high-power and high-frequency electronics. To drive this development forward, a deep understanding of fundamental material properties, such as charge carrier behavior, is essential and can also unveil new and unforeseen applications. This underscores the necessity for novel characterization tools to study group-III nitride materials and devices. The optical Hall effect (OHE) emerges as a contactless method for exploring the transport and electronic properties of semiconductor materials, simultaneously offering insights into their dielectric function. This non-destructive technique employs spectroscopic ellipsometry at long wavelengths in the presence of a magnetic field and provides quantitative information on the charge carrier density, sign, mobility, and effective mass of individual layers in multilayer structures and bulk materials. In this paper, we explore the use of terahertz (THz) OHE to study the charge carrier properties in group-III nitride heterostructures and bulk material. Examples include graded AlGaN channel high-electron-mobility transistor (HEMT) structures for high-linearity devices, highlighting the different grading profiles and their impact on the two-dimensional electron gas (2DEG) properties. Next, we demonstrate the sensitivity of the THz OHE to distinguish the 2DEG anisotropic mobility parameters in N-polar GaN/AlGaN HEMTs and show that this anisotropy is induced by the step-like surface morphology. Finally, we present the temperature-dependent results on the charge carrier properties of 2DEG and bulk electrons in GaN with a focus on the effective mass parameter and review the effective mass parameters reported in the literature. These studies showcase the capabilities of the THz OHE for advancing the understanding and development of group-III materials and devices. [ABSTRACT FROM AUTHOR]

The binary nitride coatings corresponding to Ti, Zr, Nb, Mo, and Ta have good thermal stability, hardening wear resistance, and high-temperature oxidation resistance. Therefore, the high-entropy alloy nitride coating composed of these five elements is expected to show excellent mechanical properties, and it is suitable for extending tool life in dry-cutting environments. In this paper, (TiZrNbMoTa)Nx high-entropy nitride films were synthesized using a multitarget nonequilibrium magnetron sputtering technique. The paper aimed at investigating the effects of different nitrogen flow rates (FN) on the microstructure and mechanical properties of the films. The results show that, with the increase in FN, the deposition rate gradually decreased, the films exhibited a face-centered cubic structure, and the grain gradually changed from coarse columnar crystals to ultrafine grain structures. The hardness, elastic modulus, and binding force all showed a tendency to increase and then decreased with increasing FN. The hardness and elastic modulus reached their maximum values of 34.39 and 400.97 GPa, respectively, at an FN of 60 SCCM, and the formation of covalent bonds and grain refinement promoted the increase in hardness. This research provided a theoretical foundation for designing and preparing high-entropy ceramic coatings with high performance. [ABSTRACT FROM AUTHOR]

The design and development of efficient nitride photocatalysts have attracted much attention. Herein, two-dimensional mesoporous Ta 3 N 5 is successfully synthesized through a simple sol-gel process with filter paper as a biological template and a combination of vacuum nitriding reactions. The prepared Ta 3 N 5 shows a wide light response range up to the near infrared (NIR) region due to the nitrogen vacancies generated from substitution of N3− for O2− ions during vacuum nitridation. Significantly, such a narrow bandgap (∼1.99 eV) still satisfies the redox potential of water splitting in thermodynamics. The experimental results show that the Ta 3 N 5 photocatalyst exhibits an enhanced hydrogen production rate of 34.6 μmol h−1 g−1, which is 3.9 and 2.1 times higher than that of Ta 2 O 5 and partial nitridation of Ta 2 O 5 (N–Ta 2 O 5), respectively. This enhanced photocatalytic performance could be attributed to the high specific surface area to provide reactive active sites, substitution of N3− for O2− ions to optimize the band structure, and special two-dimensional mesoporous structure to shorten the charge transfer distance. This work provides a new perspective for the preparation of two-dimensional nitride materials by a biological template method combining vacuum nitriding with enhanced photocatalytic performance. Two-dimensional mesoporous Ta 3 N 5 is synthesized by a simple sol-gel process with filter paper as a biological template and vacuum nitriding reaction, leading to an efficient photocatalytic performance. [Display omitted] • Two-dimensional mesoporous Ta 3 N 5 was prepared by a biological template. • The prepared Ta 3 N 5 shows a wide light response range up to the near infrared region. • The special two-dimensional structure shortens the charge transfer distance. • The Ta 3 N 5 photocatalyst shows a superior hydrogen production performance. [ABSTRACT FROM AUTHOR]

The massive residues of tetracycline (TC) have caused serious harm to the human body and the environment, so it is urgent to explore a portable, on-site, sensitive and selective method to detect TC. In this study, a dual response ratiometric fluorescent probe (S,O-C3N4QDs-CitNa-Eu3+) for detecting TC was constructed by mixing sodium citrate (CitNa), europium ion (Eu3+) and sulfur and oxygen co-doped graphite phase carbon nitride quantum dots (S,O-C3N4QDs) solution in a specific proportion. The S,O-C3N4QDs was initially synthesized by using citric acid and thiourea as the precursors via a hydrothermal route. The blue fluorescence of S,O-C3N4QDs (λem = 445 nm) was decreased while the red fluorescence of Eu3+ was increased (λem = 620 nm) own to the synergistic effect of internal filter effect, static quenching and antenna effect when TC was added to the mixed system containing CitNa and Eu3+. As a result, the ultra-sensitive detection of TC was realized from 0.25 to 120 μM with a detection limit of 1.3 nM. An obvious color change of the solution from blue to purple to red with continuous adding TC was observed such that the semi-quantitative detection of TC can be realized. Moreover, a smartphone APP monitoring platform based on test paper was constructed by using color scanning application, demonstrating that the ratiometric fluorescent probe constructed in this work has great potential in medical and environmental fields. [ABSTRACT FROM AUTHOR]

Nitrides are the leading semiconductor material used for the fabrication of high electron mobility transistors (HEMTs). They exhibit piezoelectric properties, which, coupled with their high mechanical stiffness, expand their versatile applications into the fabrication of piezoelectric devices. Today, due to advances in device technology that result in a reduction in the size of individual transistor elements and due to increased structural complexity (e.g., multi-gate transistors), the integration of piezoelectric materials into HEMTs leads to an interesting occurrence, namely acoustic emission from the transistor gate due to piezoelectric effects. This could affect the device's performance, reliability, and durability. However, this phenomenon has not yet been comprehensively described. This paper aims to examine this overlooked aspect of AlGaN/GaN HEMT operation, that is, the acoustic emission from the gate region of the device induced by piezoelectric effects. For this purpose, dedicated test structures were designed, consisting of two narrow 1.7 μm-wide metallization strips placed at distances ranging from 5 μm to 200 μm fabricated in AlGaN/GaN heterostructures to simulate and examine the gate behavior of the HEMT transistor. For comparison, the test device structures were also fabricated on sapphire, which is not a piezoelectric material. Measurements of acoustic and electrical interactions in the microwave range were carried out using the "on wafer" method with Picoprobe's signal–ground–signal (SGS)-type microwave probes. The dependence of reflectance |S11| and transmittance |S21| vs. frequency was investigated, and the coupling capacitance was determined. An equivalent circuit model of the test structure was developed, and finite element method simulation was performed to study the distribution of the acoustic wave in the nitride layers and substrate for different frequencies using Comsol Multiphysics software. At frequencies up to 2–3 GHz, the formation of volume waves and a surface wave, capable of propagating over long distances (in the order of tens of micrometers) was observed. At higher frequencies, the resulting distribution of displacements as a result of numerous reflections and interferences was more complicated. However, there was always the possibility of a surface wave occurrence, even at large distances from the excitation source. At small gate distances, electrical interactions dominate. Above 100 µm, electrical interactions are comparable to acoustic ones. With further increases in distance, weakly attenuated surface waves will dominate. [ABSTRACT FROM AUTHOR]

Film bulk acoustic-wave resonators (FBARs) are widely utilized in the field of radio frequency (RF) filters due to their excellent performance, such as high operation frequency and high quality. In this paper, we present the design, fabrication, and characterization of an FBAR filter for the 3.0 GHz–3.2 GHz S-band. Using a scandium-doped aluminum nitride (Sc0.2Al0.8N) film, the filter is designed through a combined acoustic–electromagnetic simulation method, and the FBAR and filter are fabricated using an eight-step lithographic process. The measured FBAR presents an effective electromechanical coupling coefficient ( k e f f 2 ) value up to 13.3%, and the measured filter demonstrates a −3 dB bandwidth of 115 MHz (from 3.013 GHz to 3.128 GHz), a low insertion loss of −2.4 dB, and good out-of-band rejection of −30 dB. The measured 1 dB compression point of the fabricated filter is 30.5 dBm, and the first series resonator burns out first as the input power increases. This work paves the way for research on high-power RF filters in mobile communication. [ABSTRACT FROM AUTHOR]

The development of environmentally friendly catalysts for organic transformations is of great importance in the field of green chemistry. Aldehyde oxidation reactions play a crucial role in various industrial processes, including the synthesis of pharmaceuticals, agrochemicals, and fine chemicals. This paper presents the synthesis and evaluation of a new metallosalen carbon nitride catalyst named Co(salen)@g-C3N4. The catalyst was prepared by doping salicylaldehyde onto carbon nitride, and subsequently, incorporating cobalt through Schiff base chemistry. The Co(salen)@g-C3N4 catalyst was characterized using various spectroscopic techniques including Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), Infrared Spectroscopy (IR), and Thermogravimetric Analysis (TGA). Furthermore, after modification with salicylaldehyde, the carbon nitride component of the catalyst exhibited remarkable yields (74–98%) in oxidizing various aldehyde derivatives (20 examples) to benzoic acid. This oxidation reaction was carried out under mild conditions and resulted in short reaction times (120–300 min). Importantly, the catalyst demonstrated recyclability, as it could be reused for five consecutive runs without any loss of activity. The reusable nature of the catalyst, coupled with its excellent yields in oxidation reactions, makes it a promising and sustainable option for future applications. [ABSTRACT FROM AUTHOR]

Fe/N-doped carbon (Fe-NC) is an excellent base-metal catalyst for use in an electrocatalytic oxygen reduction reaction (ORR) with high activity. In this paper, graphite phase carbon nitride (g-C3N4) was first obtained from the pyrolyzing of melamine, and then different proportions of FeCl3 were separately doped into g-C3N4 to further prepare the Fe-NC catalyst. The Fe-NC catalyst was applied in an ORR reaction, and the results show that the Fe-NC catalyst doped with 0.5 mmol FeCl3 possesses exceptional electrocatalytic performance, with an onset potential of 0.96 V and a half-wave potential of 0.81 V, which approaches that of a Pt/C catalyst. Meanwhile, the Fe-NC catalyst displays high stability and methanol resistance. The results supply a new way to prepare efficient ORR electrocatalysts. [ABSTRACT FROM AUTHOR]

In this paper, an n-i-p-type GaN barrier for the final quantum well, which is closest to the p-type GaN cap layer, is proposed for nitride light-emitting diodes (LEDs) to enhance the confinement of electrons and to improve the efficiency of hole injection. The performances of GaN-based LEDs with a traditional GaN barrier and with our proposed n-i-p GaN barrier were simulated and analyzed in detail. It was observed that, with our newly designed n-i-p GaN barrier, the performances of the LEDs were improved, including a higher light output power, a lower threshold voltage, and a stronger electroluminescence emission intensity. The light output power can be remarkably boosted by 105% at an injection current density of 100 A/cm2 in comparison with a traditional LED. These improvements originated from the proposed n-i-p GaN barrier, which induces a strong reverse electrostatic field in the n-i-p GaN barrier. This field not only enhances the confinement of electrons but also improves the efficiency of hole injection. [ABSTRACT FROM AUTHOR]

In this paper, ultrathin layers of carbon nitride were obtained by dissolving urea in different amounts of water and used as a carrier to prepare catalysts for formic acid dehydrogenation. The catalytic activity of the carbon nitride supported Pd catalyst in formic acid dehydrogenation was investigated. The ratio of urea to water played a key role in the type and content of nitrogen-containing functional groups, and then enhanced the catalytic performance by regulating the electronic properties of Pd. The Pd/CN-U1W5 catalyst exhibited excellent catalytic activity for the production of hydrogen from formic acid with an initial TOF of 1058 h−1 at 348 K. It was found that the high catalytic performance of the catalyst could be attributed to the strong interaction between Pd nanoparticles and pyridinic N, small Pd nanoparticle size and highly dispersed Pd nanoparticles. [ABSTRACT FROM AUTHOR]

Transition metal nitride (TMN) films with excellent hardness and lubricating performance are versatile low dimension materials, which are widely used in various fields including industries, transportation, aerospace, and so on. This paper introduces one film design strategy and provides a review of the mechanisms for strengthening and lubricating nitride films. The design strategy refers to two aspects which determine the structures, the performance, the components, and the chemical constitutions of nitride films The strengthening mechanisms of nitride films are then illuminated in detail, including the solid solution effect, the grain size effect, the secondary phase effect, the stress or stress field effect, the template effect, and the valence electron concentration effect. Five lubricating mechanisms are next summarized, including the easy-shear nature, the tribo-chemical reactions, the lubricious fluorides, the textured contact surface, and the synergistic effect. This paper aims to give a comprehensive introduction for understanding the mechanisms of strengthening and lubrication of nitride films for students and researchers, as well as to understand the current research progress in nitride films for exploring research gaps. [ABSTRACT FROM AUTHOR]

In many photocatalytic reaction paths, the breaking of the first CO bond in a CO2 molecule is often the key step that becomes the rate‐controlled reaction step. In this paper, a graphitic carbon nitride (g‐C3N4) supported nickel single‐atom catalyst (Ni@g‐C3N4) was successfully constructed, and the mechanism of CO2 catalytic reduction was systematically studied based on density functional theory (DFT). The introduction of nickel promotes the adsorption of small molecules, especially for the CO2 activation. According to density of states (DOS) and frontier orbital analysis, the photogenerated carriers tend to jump from nitrogen atoms to carbon atoms, forming an electron transfer in real space, after g‐C3N4 is excited by light. With the appearance of nickel‐doped levels, the DOS of Ni@g‐C3N4 is no longer symmetric with respect to the spin up and down, especially around the original band gap of g‐C3N4. Single‐atom nickel has abundant frontier orbitals and high activity and is a favourable place for chemical reactions. The presence of surface hydrogen can promote the recovery of CO2, and the energy barrier of Ni@g‐C3N4 with hydrogen is only 15% of the clean g‐C3N4 surface. This paper provides a new idea for the development of efficient single‐atom catalysts for CO2 reduction. [ABSTRACT FROM AUTHOR]

Modeling and understanding properties of materials from first principles require knowledge of the underlying atomistic structure. This entails knowing the individual chemical identity and position of all atoms involved. Obtaining such information for macro-molecules, nano-particles, and clusters and for the surface, interface, and bulk phases of amorphous and solid materials represents a difficult high-dimensional global optimization problem. The rise of machine learning techniques in materials science has, however, led to many compelling developments that may speed up structure searches. The complexity of such new methods has prompted a need for an efficient way of assembling them into global optimization algorithms that can be experimented with. In this paper, we introduce the Atomistic Global Optimization X (AGOX) framework and code as a customizable approach that enables efficient building and testing of global optimization algorithms. A modular way of expressing global optimization algorithms is described, and modern programming practices are used to enable that modularity in the freely available AGOX Python package. A number of examples of global optimization approaches are implemented and analyzed. This ranges from random search and basin-hopping to machine learning aided approaches with on-the-fly learnt surrogate energy landscapes. The methods are applied to problems ranging from supported clusters over surface reconstructions to large carbon clusters and metal-nitride clusters incorporated into graphene sheets. [ABSTRACT FROM AUTHOR]

We demonstrate the use of Nitride semiconductors as the light emitting layer in a series of devices, from Visible emitting LEDs, to far‐UVC LEDs and novel light emitting devices. [ABSTRACT FROM AUTHOR]

Friction and wear are two critical tribological factors that instigate unavoidable failures of moving components in the mechanical system. Additionally, these factors have a huge impact on global energy consumption, economy, and CO 2 emissions. Minimization of friction and wear in mechanical systems is rather challenging, however, significant advancement has been achieved in the development of new techniques to mitigate these tribological issues. Surface coating is one of the most commonly used techniques to reduce/eliminate tribological failures. Though a wide range of hard and anti-wear coating materials (metallic alloys, carbon, metallic glasses, polymers, ceramics, and composites) have been developed in the last few decades, however, ceramic coatings have always been a prime interest to researchers owing to their outstanding hardness, wear resistance, corrosion resistance, and damping capacity. Specifically, nitride ceramic coatings have been passed a long journey as hard and wear-resistance protective coatings in multiple industries such as manufacturing, automobile, aerospace, etc. This article reviews the journey of the development of nitride coatings for tribological applications. These developments include first-, second-, and third-generation nitride ceramic coatings, which include binary, ternary, multi-elemental as well as multi-layered coating compositions. This review paper sheds light on the available literature, merits, demerits, and applications of all nitride ceramics coatings for tribological applications. Recently, an innovation in nitride ceramic coatings has been reported, which is the utilization of the high entropy concept in these coatings, which has been reported to improve their tribological properties tremendously. This review paper also delivers a comprehensive review of high-entropy nitride ceramic coatings (both equimolar and non-equimolar compositions) for tribological applications, which is the latest and hot topic for researchers working on ceramics coatings and tribology. At last, this review paper identifies the gaps and provides the future possibilities of research in this area. [ABSTRACT FROM AUTHOR]

This paper presents the design, fabrication, and characterization of cantilever-type resonators with a novel stacked structure. Aluminum nitride is adopted as the material for both the structural layer and the piezoelectric layer; this simplifies the fabrication process and improves the quality factor of the resonator. Both in-plane and out-of-plane flexural modes were investigated. The effect of the structural dimensions and electrode patterns on the resonator's performance were also studied. Finite-element simulations and experiments examining anchor loss and thermoelastic damping, which are the main loss mechanisms affecting the quality factor of these resonators, were carried out. The optimal structural dimensions and electrode patterns of the cantilever-type resonators are presented. A quality factor of 7922 with a motional impedance of 88.52 kΩ and a quality factor of 8851 with a motional impedance of 67.03 kΩ were achieved for the in-plane and out-of-plane flexural-mode resonators, respectively. The proposed resonator design will contribute to the development of high-performance devices such as accelerometers, gyroscopes, and pressure sensors. ARTICLE HIGHLIGHTS: HIGHLIGHTS • A novel structure for cantilever resonators with AlN structural layers is proposed, which helps to achieve higher performance. • The effect of geometric design and electrode patterns on the Q value and the optimization methods were studied. • The Q value reached up to 8000 after optimization, which is the highest among similar resonators in previous work. [ABSTRACT FROM AUTHOR]

This paper presents an analysis of non-metallic inclusions occurring in high-silicon steels containing about 3% Si of terms of their type, volume fraction and morphology. The inclusions were divided into 3 main groups: oxides, sulfides, nitrides which together can also form complex. The work was based on numerous metallographic observations in two sections (longitudinal and transverse to the rolling direction). The study was performed on three casts differing in chemical composition. The analyzed casts were characterized by a different content of non-metallic inclusions, which can be associated with slight differences in chemical composition. The analyzed results showed that the most common inclusions were oxides and nitrides. Sulfides occurred sporadically. [ABSTRACT FROM AUTHOR]

Carbon nitride MXene exhibits good metal conductivity, high photothermal conversion, carrier mobility, and high exposure of active sites, which makes it a promising co-catalyst for photothermal synergistic transformation of CO2. In this paper, Ti3CN/TiO2 heterojunction was constructed in situ using Ti3CN as TiO2 precursor to investigate the performance of Ti3CN MXene in photothermal synergistic transformation of CO2, and then the monolayer structure was utilized to enhance the interfacial charge transfer and improve the photothermal catalytic activity of Ti3CN. The catalysts were characterized by SEM, XRD, XPS, and UV-Vis DRS, and it was found the heterojunction constructed by monolayer MXene had a narrower bandgap and a higher carrier generation mobility, which, combined with the catalytic activity test, proved the single monolayer Ti3CN MXene had better photothermal synergistic conversion efficiency of CO2, and the heterojunction yield was 11.36 μmol·g−1·h−1 after layering, compared with that before layering (9.41%), which was 1.2 times higher than that before layering (9.41 μmol·g−1·h−1). [ABSTRACT FROM AUTHOR]

This paper proposes a robust to defects and short length device (RDSLD), a newly in-plane resonant tunneling diode (RTD), and its ac-modeling with the minimum length of 3 nm. The proposed structure has robust performance in the presence of defects. It also has a high degree of flexibility in tuning electronic specifications. By using bipolar doping and a special h-boron nitride barrier pattern, these unique features are obtained. The simulation results verify that the proposed structure has the potential for replacing conventional RTD diodes. Such that the peak-to-valley ratio (PVR) and the maximum current of 4500, 450 nA for perfect bowtie and 3.45, 1256 nA for rhombic barrier shape structure are obtained, respectively. Also, negative differential resistance (NDR) is observed in all of the structures with vacancy and impurity defects. The effect of the geometrical parameters on the charge transmission of the device is another issue that is addressed in this paper. Furthermore, the analytical and numerical capacitance model parameters are presented. [ABSTRACT FROM AUTHOR]

The simultaneous production of hydrogen and biomass-based chemicals from biomass-derived feedstock aqueous solutions via photocatalysis is appealing because no additional sacrificial agent is needed. However, limited success has been achieved. This paper reports efficient nori-shaped carbon nitride-based photocatalysts with potassium/oxygen co-doping and cyano group introduction for efficient conversion of biomass-derived monosaccharides to produce lactic acid and hydrogen simultaneously. The obtained photocatalyst has an adjustable bandgap, fast migration/separation rate of photo-generated carriers and displays excellent photocatalytic performance with respect to xylose conversion (∼95.0%), lactic acid selectivity (90.5%) and hydrogen generation (∼33 380 μmol g−1 h−1) in the presence of visible light. The h+, ˙OH, ˙O2− and 1O2 drive xylose conversion and lactic acid production. For biomass-derived pentoses and hexoses, the reaction system also exhibits excellent photocatalytic activity of lactic acid selectivity and hydrogen generation; the reported photocatalyst has excellent reusability. This paper provides a new perspective for hydrogen generation and biorefineries via a photocatalyst. [ABSTRACT FROM AUTHOR]

Phosphorus (P) is one of the important elements for the formation of life and plays a crucial role in several biochemical processes. Recent spectral line surveys have confirmed the existence of P-bearing molecules, especially PN and PO, in the star-formation regions, but their formation mechanisms are poorly understood. The P-bearing molecule phosphorus nitride (PN) is detected in several star-forming regions, but this molecule has been poorly studied at high gas densities (≥ 10 6 cm - 3 ) hot molecular cores. In this paper, we presented the detection of rotational emission line of PN with transition J = 3 –2 towards the hot molecular cores G10.47 + 0.03 and G31.41 + 0.31, using the Atacama Compact Array (ACA). The estimated column densities of PN for G10.47 + 0.03 and G31.41 + 0.31 using the local thermodynamic equilibrium model are (3.60 ± 0.2) × 10 13 cm - 2 and (9.10 ± 0.1) × 10 12 cm - 2 with an excitation temperature of 150 ± 25 K. The fractional abundance of PN relative to H 2 is 2.76 × 10 - 10 for G10.47 + 0.03 and 5.68 × 10 - 11 for G31.41 + 0.031. We computed the two-phase warm-up chemical model of PN to understand the chemical evolution in the environment of hot molecular cores. After chemical modeling, we claimed that PN is created in the gas phase via the neutral–neutral reaction between PO and N in the warm-up stage. Similarly, PN is destroyed via the ion–neutral reaction between H 3 O + and PN. [ABSTRACT FROM AUTHOR]

This paper presents an overview of studies dedicated to the atomic-discrete modeling of the growth process of film coatings that comprise mononitrides of transition and post-transition metals. The main modeling approaches are the Monte Carlo and molecular dynamics methods as well as their combinations with analytical contributions. The molecular dynamics method is more accurate compared to the Monte Carlo method but has disadvantages related to the time scale. Given this, the adoption of accelerated molecular dynamics methods is viewed as a promising approach for directly simulating the specified processes. These methods can be implemented just after the relaxation of the collision stage in the area of the deposited particle between the deposition events to simulate the realistic density of the incident beam and accompanied long-term mass transfer processes. [ABSTRACT FROM AUTHOR]

Lithium metal is considered a promising anode material for lithium secondary batteries by virtue of its ultra-high theoretical specific capacity, low redox potential, and low density, while the application of lithium is still challenging due to its high activity. Lithium metal easily reacts with the electrolyte during the cycling process, resulting in the continuous rupture and reconstruction of the formed SEI layer, which reduces the cycling reversibility. On the other hand, repeated lithium plating/stripping processes can lead to uncontrolled growth of lithium dendrites and a series of safety issues caused by short-circuiting of the battery. Currently, modification of the battery separator layer is a good strategy to inhibit lithium dendrite growth, which can improve the Coulombic efficiency in the cycle. This paper reviews the preparation, behavior, and mechanism of the modified coatings using metals, metal oxides, nitrides, and other materials on the separator to inhibit the formation of lithium dendrites and achieve better stable electrochemical cycles. Finally, further strategies to inhibit lithium dendrite growth are proposed. [ABSTRACT FROM AUTHOR]

This paper is focused on electrode design for piezoelectric tuning fork resonators. The relationship between the performance and electrode pattern of aluminum nitride piezoelectric tuning fork resonators vibrating in the in-plane flexural mode is investigated based on a set of resonators with different electrode lengths, widths, and ratios. Experimental and simulation results show that the electrode design impacts greatly the multimode effect induced from torsional modes but has little influence on other loss mechanisms. Optimizing the electrode design suppresses the torsional mode successfully, thereby increasing Rp/Rs by more than 80% and achieving a quality factor (Q) of 7753, an effective electromechanical coupling coefficient (kteff2) of 0.066%, and an impedance at series resonant frequency (Rm) of 23.6 kΩ. The proposed approach shows great potential for high-performance piezoelectric resonators, which are likely to be fundamental building blocks for sensors with high sensitivity and low noise and power consumption. HIGHLIGHTS: • A new strategy is explored for suppressing the multimode effect by tuning the electrode pattern of piezoelectric tuning fork resonators. • Comprehensive resonator performance improvement is achieved by effective multimode suppression. • Crucial parameters are improved simultaneously with Q = 7753, kteff2 = 0.066%, Rm = 23.6 kΩ, and an 86% higher Rp/Rs. [ABSTRACT FROM AUTHOR]

Chromium nitrides such as CrN and Cr2N are often used for corrosion and wear resistant applications. In order to understand the thermodynamic stability of the nitrides, Pourbaix diagrams will be extremely useful. In this paper, Pourbaix diagrams are constructed for CrN and Cr2N using thermodynamical data for species at 298 K (25 °C) and at a concentration of 10−6 M for aqueous species. These diagrams are useful indicators for the stable regions in which these compounds can be used. The diagrams show that passive Cr2O3 films form on the surfaces where chromium nitride was present. It is argued that the formation of Cr2O3 films will degrade chromium nitride and make it much less useful as a wear resistant layer. However, the presence of nitrogen in solid solution is better for the stability of passive films. [ABSTRACT FROM AUTHOR]

This paper discusses the optimization of an advanced process monitoring scheme with interdicting fault detection and classification (FDC) capabilities that improved the control over the process development of Tantalum Nitride thin film resistors (TaN TFR). Its implementation in a high-volume manufacturing environment resulted in a reduction of misprocessed wafers, shorter equipment downtime, higher throughput, enhanced process visibility, and yield improvement. Along with optimizing FDC capabilities, implementing a short loop sampling plan reduced the turnaround time for early electrical characterization by a factor of four; this allowed for timely inline adjustments within the fabrication process to tighten the statistical process control (SPC) over the distribution of the process control monitor (PCM) TaN resistor value and improve thin film uniformity. [ABSTRACT FROM AUTHOR]

Graphitized carbon nitride (g-C3N4), as a metal-free, visible-light-responsive photocatalyst, has a very broad application prospect in the fields of solar energy conversion and environmental remediation. The g-C3N4 photocatalyst owns a series of conspicuous characteristics, such as very suitable band structure, strong physicochemical stability, abundant reserves, low cost, etc. Research on the g-C3N4 or g-C3N4-based photocatalysts for real applications has become a competitive hot topic and a frontier area with thousands of publications over the past 17 years. In this paper, we carefully reviewed the recent advances in the synthesis and structural design of g-C3N4 materials for efficient photocatalysts. First, the crucial synthesis parameters of g-C3N4 were fully discussed, including the categories of g-C3N4 precursors, reaction temperature, reaction atmosphere and reaction duration. Second, the construction approaches of various nanostructures were surveyed in detail, such as hard and soft template, supramolecular preorganization and template-free approaches. Third, the characteristics of different exfoliation methods were compared and summarized. At the end, the problems of g-C3N4 materials in photocatalysis and the prospect of further development were disclosed and proposed to provide some key guidance for designing more efficient and applicable g-C3N4 or g-C3N4-based photocatalysts. [ABSTRACT FROM AUTHOR]

Nitride wide-bandgap semiconductors possess a wide tunable energy bandgap and abundant coordination anionic groups. This suggests their potential to display nonlinear optical (NLO) properties in the UV wavelength spectrum. This paper reports recent progress and material discoveries in exploring UV NLO structures using nitrides. The study emphasizes their underlying structure–property correlations in order to provide a summary of the potential performance and application value of important nitride NLO crystals. Additionally, the text underscores the benefits of nitrides in terms of optical transparency, second-harmonic-generation effects, and the birefringent phase matching output wavelength limits, while addressing current issues in terms of theoretical outlook and experimental exploration. [ABSTRACT FROM AUTHOR]