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Standard thermoreflectance-based measurements have been routinely taken on thin metal transducer (Au or Al) deposited samples. This is based on the fundamental hypothesis that the reflectance change (ΔR/R) of the metal surface is directly and linearly related to the temperature change (ΔT), within a wide but finite temperature range (Trange). The quantitative study on Trange has been ignored for a long time, which would possibly cause severe measurement issues and impede the possible new applications that the thermoreflectance measurements are taken on new metals or even directly on non-metals. Here, we present an approach that combines multiple probe wavelengths' nanosecond transient thermoreflectance technique with a transient temperature rise model to study the linear relation. This method enables fast and accurate determination of the Trange and the proportional coefficient (commonly called the thermoreflectance coefficient, Cth). We studied the commonly used metal transducers (Au and Al) and found that Au illuminated at 532 nm has a considerably larger Trange (from room T to at least 225 °C), with respect to Al illuminated at 785 nm (room T to 150 °C). The linear relationships of uncommon Ni and Ti metals are valid from room temperature to ∼115 °C, illuminated at 785 and 660 nm, respectively. Non-linearity was observed for Al, Ni, and Ti metals when the temperature was elevated above the quantified Trange. This method enables a facile and reliable platform to characterize thermoreflectance properties and better understand the mechanism of thermoreflectance linear relationship. [ABSTRACT FROM AUTHOR]

Co‐free O3‐type NaNi0.5Mn0.5O2 cathode material for sodium‐ion batteries has shown great promise due to its high theoretical capacity and plentiful Na reservoir. However, the rapid capacity recession caused by harmful phase transition and large volume strain severely restricts their practical application. Herein, the obstacle is well addressed by constructing a P2&O3 biphasic structure via a customized boron‐doping strategy. The light‐weight boron doping in the interstitial position reduces the energy gap of the formation energy of P2 and O3 structure, which induces the formation of P2&O3 biphase in high Na state. In addition, the biphasic structure exhibits near zero volume strain due to the lattice interlocking effect of P2&O3, as identified by in situ X‐ray diffraction measurement. As a result, it presents a remarkable cyclability with a capacity retention of 85.2% over 1000 cycles at a high rate of 5 C. More importantly, a pouch‐type full‐cell device can exhibit a long cycling life with 70.8% capacity retention over 150 cycles at 0.1 C. This work can offer a new inspiration for designing advanced high sodium electrode materials via light element doping for future energy storage devices. [ABSTRACT FROM AUTHOR]

[Display omitted] • The surface modification can significantly raise the limiting potential with −1.24 V (Ti 2 NF 2) to −0.21 V (Ti 2 BSe 2). • hybridization of the σ 2 p and π* 2 p with Ti 3 d orbitals leads to the evident splitting and downshifting of the σ and π* orbitals. • The work function plays a crucial role to predict the NRR performance by the Gibbs free energy change of the rate-determining step, which can be regulated through the surface termination of MXenes. The electrochemical conversion of nitrogen to ammonia provides an encouraging method to substitute the traditional Haber-Bosch process, owing to its high efficiency and mild reaction conditions. The search for high-performance catalysts and comprehension of catalytic mechanisms remains significant challenges. Herein, we conduct a systematic theoretical calculation of the NRR performance and mechanism of 24 Ti 2 XT 2 (X = B, C, N; T = F, Cl, Br, I, O, S, Se, Te) MXenes with a T -vacancy to explore the influence of surface functional terminations and non-metallic center elements. Our findings demonstrate that surface functionalization significantly reduces the limiting potential by altering the rate-determining step. This change ranges from −1.24 V (Ti 2 NF 2) to −0.21 V (Ti 2 BSe 2), signifying the remarkable efficacy of modification of the surrounding environment of the exposed transition metal active center in promoting electrocatalytic performance. Detailed investigation of the charge density difference and orbital interaction reveals that the different NRR performance originates from the surface termination and non-metallic atoms regulate the electronic properties of the active Ti atoms. We also introduce the free energy change of *NNH 2 (Δ G *NNH2) as a descriptor to predict the performance of NRR, which exhibits satisfactory linear relationship with free energy change of different intermediates and displays favourable volcano plot with limiting potential. Moreover, we highlight the pivotal role of work function in tuning the energy barrier of the rate-determining step, which can be regulated through the surface modification of MXenes. Our study not only offers a comprehensive understanding of the crucial impact of surface modification on the catalytic activities of defective MXenes, but also provides a rational perspective for designing efficient NRR catalysts. [ABSTRACT FROM AUTHOR]

The recycling approach for waste printed circuit boards (WPCBs) has evolved from stabilization to value-added processes. However, the variability in the value of their components hinders the development of comprehensive WPCB recycling strategies as a whole. This paper reviews advanced recovery strategies for various fractions including base metals, precious metals, rare earth metals, hazardous metals, and nonmetals. The focal points were to elucidate the complex WPCB structure and composition, and the associated recycling challenges, and to evaluate the advanced technologies for the recovery of various fractions. From a forward-looking recycling perspective, the different fractions should be treated separately to minimize environmental impact, recycle product usage, and maximize economic benefits. A comprehensive framework for resource recovery from WPCBs is proposed to guide future research and promote a green, circular economy in electronics waste management. [ABSTRACT FROM AUTHOR]

The insertion of unsaturated organic molecules into a P−P bond of oligophosphorus compounds has the potential to expand the organophosphorus and organometallic chemistry and to make it more variable with the selective formation of desirable products. This article reviews the insertion reaction for oligophosphorus compounds and focuses in particular on non‐metals, unsaturated organic substrates, carbenes and carbene analogues as starting reagents. [ABSTRACT FROM AUTHOR]

This review summarizes the structural and synthetic aspects of heterocyclic molecules incorporating an atom of a hypervalent main-group element. The term "hypervalent" has been suggested for derivatives of main-group elements with more than eight valence electrons, and the concept of hypervalency is commonly used despite some criticism from theoretical chemists. The significantly higher thermal stability of hypervalent heterocycles compared to their acyclic analogs adds special features to their chemistry, particularly for bromine and iodine. Heterocyclic compounds of elements with double bonds are not categorized as hypervalent molecules owing to the zwitterionic nature of these bonds, resulting in the conventional 8-electron species. This review is focused on hypervalent heterocyclic derivatives of nonmetal main-group elements, such as boron, silicon, nitrogen, carbon, phosphorus, sulfur, selenium, bromine, chlorine, iodine(III) and iodine(V). [ABSTRACT FROM AUTHOR]

Recently, there has been a significant interest in the study of highly active and stable transition metalbased electrocatalysts for the oxygen evolution reaction (OER). Non-noble metal nanocatalysts with excellent inherent activity, many exposed active centers, rapid electron transfer, and excellent structural stability are especially promising for the displacement of precious-metal catalysts for the production of sustainable and "clean" hydrogen gas through water-splitting. Herein, efficient electrocatalyst N-doped nickel molybdate nanorods were synthesized on Ni foam by a hydrothermal process and effortless chemical vapor deposition. The heterostructure interface of N-NiMoO4/NiO2 led to strong electronic interactions, which were beneficial for enhancing the OER activity of the catalyst. Excellent OER catalytic activity in 1.0 M KOH was shown, which offered a small overpotential of 185.6 mV to acquire a current density of 10 mA cm-2 (superior to the commercial benchmark material RuO2 under the same condition). This excellent electrocatalyst was stable for 90 h at a constant current density of 10 mA cm-2. We created an extremely reliable and effective OER electrocatalyst without the use of noble metals by doping a nonmetal element with nanostructured heterojunctions of various active components. [ABSTRACT FROM AUTHOR]

Objectives—Metallic elements and fibrin clot properties have been linked to stroke. We examined metallic and nonmetallic elements, fibrin clot lysis time (CLT), and maximum absorbance (Absmax) in relation to ischemic stroke. Design—A case–control study of ischemic stroke patients vs. healthy individuals. Subjects and Methods—Plasma and serum were collected from 260 ischemic stroke patients (45.0% women; age, 68 ± 12 years) and 291 healthy controls (59.7% women; age, 50 ± 17 years). Fibrin CLT and Absmax were measured using a validated turbidimetric assay. Serum elements were quantified by inductively coupled plasma mass spectrometry (ICP-MS) and optical emission spectrometry (ICP-OES). Data were analyzed by bivariate correlations and multiple or logistic regression. Results—In female stroke patients, copper, lithium, and aluminum were significantly lower compared with controls; in male stroke patients, potassium was lower, and beryllium was elevated. In female and male stroke patients, iron, zinc, nickel, calcium, magnesium, sodium, and silicon were significantly lower, while strontium was elevated. Positive correlations between fibrin clot properties and metals, observed in healthy controls, were lost in ischemic stroke patients. In multivariate regression analysis, fibrin CLT and/or Absmax was associated with zinc, calcium, potassium, beryllium, and silicon in stroke patients and with sodium, potassium, beryllium, and aluminum in controls. In logistic regression analysis, stroke was independently associated with lithium, nickel, beryllium, strontium, boron, and silicon and with sodium, potassium, calcium, and aluminum but not with fibrin CLT/Absmax. Conclusions—Various elements were associated with fibrin clot properties and the risk of ischemic stroke. Lithium, sodium, calcium, and aluminum abrogated the association of fibrin clot properties with ischemic stroke. [ABSTRACT FROM AUTHOR]

Schematic diagram representation the introduction of selenium and iron synergistically modulate the d-band center of Ni 3 S 2 to enhance oxygen evolution reaction (OER) and urea oxidation reaction (UOR). [Display omitted] • The introduction of selenium and iron synergistically modulated the d-band center of Ni 3 S 2 , resulting in the enhanced catalytic activity for the oxygen evolution reaction (OER) and urea oxidation reaction (UOR). • By adjusting the position of the d-band center, it is possible to optimize the adsorption and desorption energies of SeFe-Ni 3 S 2 towards urea molecules, as well as the overpotential for OER (η OER) and the limiting potential for UOR (U L). • The synthesized SeFe-Ni 3 S 2 presents as 3.9 nm lamellar structure with a larger specific surface area leading to the exposure of more active sites. Efficient production of green hydrogen energy is crucial in addressing the energy crisis and environmental concerns. The oxygen evolution reaction (OER) poses a challenge in conventional overall water electrolysis due to its slow thermodynamically process. Urea oxidation reaction (UOR) offers an alternative anodic oxidation method that is highly efficient and cost-effective, with favorable thermodynamics and sustainability. Recently, there has been limited research on bifunctional catalysts that exhibit excellent activity for both OER and UOR reactions. In this study, we developed a selenium and iron co-doped nickel sulfide (SeFe-Ni 3 S 2) catalyst that demonstrated excellent Tafel slopes of 53.9 mV dec−1 and 16.4 mV dec−1 for OER and UOR, respectively. Density Functional Theory (DFT) calculations revealed that the introduction of metal (iron) and nonmetallic elements (selenium) was found to coordinate the d-band center, resulting in improved adsorption/desorption energies of the catalysts and reduced the overpotentials and limiting potentials for OER and UOR, respectively. This activity enhancement can be attributed to the altered electronic coordination structure after the introduction of selenium (Se) and iron (Fe), leading to an increase in the intrinsic activity of the catalyst. This work offers a new strategy for bifunctional catalysts for OER and UOR, presenting new possibilities for the future development of hydrogen production and novel energy conversion technologies. It contributes towards the urgent search for technologies that efficiently produce green hydrogen energy, providing potential solutions to mitigate the energy crisis and protect the environment. [ABSTRACT FROM AUTHOR]

Special structures and good characteristics make 2D iodine structures more appealing and valuable at high pressures. The electrical transport of such 2D iodine structures is theoretically studied here, taking the doping of nonmetal elements into account. Most doped devices show considerably greater equilibrium conductance than the original device. Devices with the dopants in lower atomic numbers show higher conductance. The transmission spectrum all around E F can be improved by the doping of nonmetal elements. Essentially, DDOS can well explain the variations in electron transmission probability caused by the doping of nonmetal atom for most doped devices, serving as one main inherent factor in electron transport. The influence of nonmetal dopants on transmission eigenstates varies according to the main group, essentially depending on the number of transferring channels and the strength of transmission eigenstates. Influenced by the bias, the conductance of such innovative devices fluctuates but with varied amplitudes. Every doping mode can enhance the conductance by applying the bias and such biases for all doping modes must cover lower biases. Unlike the dopants in larger atomic numbers, the devices with the dopants in smaller atomic numbers show much difference in size between the voltage interval that enhances and the voltage interval that weakens. The current grows linearly with bias. Nonmetal doping enables the current to increase at low voltages and decrease at high voltages, compared with the undoped device. The improved and attenuated effect on the current is good for doped devices with nonmetal elements in smaller atomic numbers, but poor in higher atomic numbers. These discoveries contribute significantly to our understanding of the effects of defects and elemental adsorption on electrical characteristics and give strong evidence for the use of new-type 2D iodine materials in controlled electronics and sensors. [ABSTRACT FROM AUTHOR]

We have simulated the configuration of perovskite CsPbBr 3 quantum dot (QD), sodium borosilicate (SBS) glass matrix, and the combination of these two, namely CsPbBr 3 QDs embedded SBS glass. We delineate a microscope porthole containing ∼100,000 atoms and with a dimension of ∼30 nm × 30 nm × 1 nm, using the classical molecular dynamics (CMD) benefiting from graphics processing unit (GPU) acceleration. We quantify the structural properties of glass matrix and determined the crystallization of QDs, in excellent agreement with experimental observations. Based on analysis the of boron coordination, structural undulation influenced by the K value (K SiO 2 /B 2 O 3), we demonstrate the significant compositional repulsion in the combination derived from electronegative nonmetal elements, namely oxygen (O) and bromine (Br). As the K value decreases, indicating an increase in the proportion of B 2 O 3 and a decrease in the proportion of SiO 2 , the [BO 3 ]/[BO 4 ] ratio increases, resulting in a glass matrix with a stronger repulsive 'anionic sea' and a more relaxed encapsulated environment for CsPbBr 3 QD. This creates greater repulsion for the allocation of oxide and bromide, and a more suitable space for the crystallization of CsPbBr 3 clusters, which in turn regulates the formation of CsPbBr 3 QDs. These results constructively extend our understanding of the microstructure of CsPbBr 3 QDs embedded SBS glasses, and provide valuable insights for the engineering of CsPbBr 3 QDs in SBS glasses on high luminescent CsPbBr 3 QDs embedded glasses. [ABSTRACT FROM AUTHOR]

The mixed protonic--electronic conductor of BaCe0.5Fe0.5O3-δ can be automatically decomposed into a dual-phase material of the cerium-rich oxide BaCe0.85Fe0.15O3-δ (BCFe8515) and the iron-rich oxide BaCe0.15Fe0.85O3-δ (BCFe1585). The BaCe0.5Fe0.5O3-δ membrane possessed an extremely high hydrogen (H2) permeation flux, but poor stability. Therefore, in this work, for the first time, the nonmetal P is doped to increase the proportion of the BaCe0.85Fe0.15O3-δ (P-doped Ce-rich) phase to improve the stability of the dual-phase membrane. The developed dual-phasic ceramic membranes of BaCe0.5Fe0.5-xPxO3-δ (BCFePx) (x = 0, 0.025, 0.05, 0.1) exhibit enhanced stability compared to their parent oxides. Under the condition of 950°C, feed gas with dry 50% H2-50% He and sweep gas with wet Ar, the H2 permeation flux of BCFeP0.05 membrane stabilized at 1.56 mL min-1 cm-2 after the long-term stability test for 480 h. The enhanced stability resulted from the increase of the P-doped Ce-rich phase content and the inhibition of Fe2O3 phase precipitation from the BaCe0.15Fe0.85O3-δ (P-doped Fe-rich) phase in the reducing atmosphere by doping non-metal P element. [ABSTRACT FROM AUTHOR]

Heteroatom-doping of carbonaceous materials and (nano)structures permits alteration of their fundamental physicochemical properties and thus amplifies the range of their potential applications. While nitrogen-doping dominated this research area, doping and co-doping with other non-metal and metal elements proved to be equally efficient strategies to tune carbonaceous materials' characteristics. Heavier chalcogens are considered atypical carbon dopants due to their large atomic radii, high polarizability, and electronegativity comparable to that of carbon. Se-doped carbons are much less common than their S-doped counterparts, yet recently, they appeared as attractive functional materials for a range of sustainable technologies. This review depicts progress in Se-doped and co-doped carbonaceous materials from 2012 to the present. The report is divided into three major parts: first, the versatile chemistry of selenium and the significance of Se-doping is presented, followed by a variety of preparation methods, and finally, prominent examples of advanced applications in the fields of heterogeneous (electro)catalysis, energy conversion/storage, and pollutant neutralization. [ABSTRACT FROM AUTHOR]

Catalysts involving post‐transition metals have shown almost invincible performance on generating formate in electrochemical CO2 reduction reaction (CO2RR). Conversely, Cu without post‐transition metals has struggled to achieve comparable activity. In this study, a sulfur (S)‐doped‐copper (Cu)‐based catalyst is developed, exhibiting excellent performance in formate generation with a maximum Faradaic efficiency of 92 % and a partial current density of 321 mA cm−2. Ex situ structural elucidations reveal the presence of abundant grain boundaries and high retention of S−S bonds from the covellite phase during CO2RR. Furthermore, thermodynamic calculations demonstrate that S−S bonds can moderate the binding energies with various intermediates, further improving the activity of the formate pathway. This work is significant in modifying a low‐cost catalyst (Cu) with a non‐metallic element (S) to achieve comparable performance to mainstream catalysts for formate generation in industrial grade. [ABSTRACT FROM AUTHOR]

Catalysts involving post‐transition metals have shown almost invincible performance on generating formate in electrochemical CO2 reduction reaction (CO2RR). Conversely, Cu without post‐transition metals has struggled to achieve comparable activity. In this study, a sulfur (S)‐doped‐copper (Cu)‐based catalyst is developed, exhibiting excellent performance in formate generation with a maximum Faradaic efficiency of 92 % and a partial current density of 321 mA cm−2. Ex situ structural elucidations reveal the presence of abundant grain boundaries and high retention of S−S bonds from the covellite phase during CO2RR. Furthermore, thermodynamic calculations demonstrate that S−S bonds can moderate the binding energies with various intermediates, further improving the activity of the formate pathway. This work is significant in modifying a low‐cost catalyst (Cu) with a non‐metallic element (S) to achieve comparable performance to mainstream catalysts for formate generation in industrial grade. [ABSTRACT FROM AUTHOR]

Green Hydrogen emerges as a promising energy solution in the quest for achieving Net Zero goals. The application of particulate semiconductors in photocatalytic water splitting introduces a potentially scalable and economically viable technology for converting solar energy into hydrogen. Overcoming the challenge of efficiently transferring photoelectrons and photoholes for both reduction and oxidation on the same catalyst is a significant hurdle in photocatalysis. In this context, we introduce highly efficient crystalline elemental boron nanostructures as photocatalysts, employing a straightforward and scalable synthesis method yield green hydrogen production without the need for additional co-catalysts or sacrificial agents. The resulting photocatalyst demonstrates stability and high activity in H 2 production, achieving over 1 % solar-to-hydrogen energy conversion efficiency (>15,000 μmol. g−1.h−1) during continuous 12-h illumination. This efficiency is credited to broad optical absorption and the crystalline nature of boron nanostructures, paving the way for potential scale-up of reactors using crystalline boron photocatalysts. [Display omitted] • Inexpensive, scalable, and novel synthesis process for Non-metallic single element catalysts. • Wide range optical absorption (UV–Vis–NIR). The H 2 production was achieved by only illuminating visible and NIR regions of light. • The H 2 production efficiency is more than 15,000 μM/gm/hr. • The high yield of H 2 production was achieved without the aid of co-catalysts and sacrificial reagents. • Long term stable performance H 2 production over 72 h is reported. [ABSTRACT FROM AUTHOR]

Seeded growth has been widely accepted as a vital synthetic strategy to achieve noble metal NCs with high quality (i.e., high uniformity in size/shape) and versatile control over the morphology and structure. To realize such a goal in controlled synthesis, the change in the chemical state of the particle surface during the growth stage is of great importance, and has gradually attracted research attention. Typically, the capping agents that are used to suspend nanoparticles in a solvent, such as surfactant molecules, polymers, or inorganic anions, can easily adsorb and desorb on the surface during the growth procedure, and would not significantly affect the interfacial strain between the seed metal and deposited metal. In contrast, if the nanoparticle surface is modified with metallic or non-metallic elements in distinct forms, the surface lattice parameters would be varied to a great extent, thus causing notable change to the interfacial strain and the following growth pattern. In this review article, we will introduce the fundamental aspects and general principles of the doping strategy towards versatile manipulation of the seeded growth of noble metal NCs. Then, case studies of recent progress in this field will be provided and analyzed. Finally, the challenges and opportunities will be summarized. [ABSTRACT FROM AUTHOR]

Designing and developing photocatalysts with excellent performance in order to achieve efficient hydrogen production is an important strategy for addressing future energy and environmental challenges. Traditional single-phase photocatalytic materials either have a large bandgap and low visible light response or experience rapid recombination of the photogenerated carriers with low quantum efficiency, seriously hindering their photocatalytic applications. To solve these issues, an important solution is to construct wellmatched heterojunctions with highly efficient charge separation capabilities. To this end, an in situ sulfurization reaction was adopted after the deposition of Bi3+ supramolecular complex on a layered supramolecular precursor of tubular carbon nitride (TCN). X-ray diffraction (XRD) patterns confirmed that the asprepared sample has a good crystalline structure without any other impurities, while high-resolution transmission electron microscopy (HR-TEM) revealed that the heterojunction possesses a 2D structure with a layer of nano-array on its surface. Combined Fourier-transform infrared (FT-IR) spectra and energydispersive X-ray spectroscopy (EDX) revealed the interfacial interactions. Owing to the formation of the Z-scheme heterojunction, the visible light adsorption and the separation efficiency of the photo-generated carriers are both obviously enhanced, leaving the high energy electrons and high oxidative holes to participate in the photocatalytic reactions. As a result, the photocatalytic hydrogen evolution rate of Bi2S3-TCN achieves 65.2 µmol g-1]⋅h-1. This proposed green and environmentally benign route can also be applied to construct other sulfides with 2D TCN, providing some important information for the design and optimization of novel carbon-nitride-based semiconductors. [ABSTRACT FROM AUTHOR]

Background: Environmental factors play an important role in developing mental disorders. This study aimed to investigate the associations of metal and nonmetal elements in drinking water with the risk of depression and anxiety and to assess whether diets modulate these associations. Methods: We conducted a prospective cohort study including 24,285 participants free from depression and anxiety from the Yinzhou Cohort study in the 2016–2021 period. The exposures were measured by multiplying metal and nonmetal element concentrations in local pipeline terminal tap water samples and total daily drinking water intakes. Cox regression models adjusted for multi-level covariates were used to estimate adjusted hazard ratios (aHRs) and 95% confidence intervals (95%CIs). Results: During an average follow-up period of 4.72 and 4.68 years, 773 and 1334 cases of depression and anxiety were identified, respectively. A 1 standard deviation (SD) increase in manganese exposure reduced the incidence of depression by 8% (HR 0.92, 95%CI 0.88 to 0.97). In contrast, with a 1 SD increase in copper and cadmium exposure, the incidence of depression increased by 6% (HR 1.06, 95%CI 1.01 to 1.11) and 8% (HR 1.08, 95%CI 1.00 to 1.17), respectively. The incidence of anxiety increased by 39% (HR 1.39, 95%CI 1.20 to 1.62), 33% (HR 1.33, 95%CI 1.03 to 1.71), and 14% (HR 1.14, 95%CI 1.03 to 1.25) respectively for a 1 SD increase in manganese, iron, and selenium exposure. Diets have a moderating effect on the associations of metal and nonmetal elements with the risk of anxiety. Stronger associations were observed in older, low-income groups and low-education groups. Conclusions: We found significant associations between exposure to metal and nonmetal elements and depression and anxiety. Diets regulated the associations to some extent. [ABSTRACT FROM AUTHOR]

Given the elevated expense and constrained accessibility of platinum, the primary catalyst employed in electrocatalytic hydrogen evolution, it becomes essential to pinpoint an alternative catalyst demonstrating exceptional catalytic efficacy and broader scalability potential. In this study, we undertook an exhaustive inquiry into the electrocatalytic activity concerning hydrogen evolution of the monolayer Janus MoXTe (where X represents S and Se) utilizing first-principle calculation. Furthermore, an evaluation of the performance of defective MoXTe structures was conducted. Our findings illuminate that the incorporation of non-metallic elements like B, C, N, and P into MoXTe can be employed to finely adjust the Gibbs free energy (ΔG H) to approximately 0 eV. Particularly, the doping of B and P into the 1T phase of MoSTe (1T-MoSTe-B@ represents 1T phase of MoSTe-B@ and 1T-MoSTe-P@ represents 1T phase of MoSTe-P@), the doping of P into the 1T′ phase of MoSTe (1T′ phase of MoSTe-P@), and the doping of P into the 1T′ phase of MoSeTe (1T′ phase of MoSeTe-P@) exhibit ΔG H values that are in close proximity to zero (ΔG H = 0.02, −0.03, 0.06, and −0.14 eV, respectively). Through further analysis, we found that the pristine and defective structures all exhibit metallic properties. And the doping of P improved HER performance more effectively among four nonmetallic dopants. In details, H get 0.21, 0.29, 0.43 and 0.28 e on doping of B and P into 1T phase MoSTe (1T phase of MoSTe-B@ and 1T phase of MoSTe-P@) and the doping of P into 1T′ phase MoSeTe (1T' phase of MoSeTe-P@). This study provides strategies for the design of MoXTe monolayer electrocatalysts, and it is expected to be applied to HER catalysts in affordable and efficient manner. • Screening of Catalytic Activity of 1T, and 1T′ phases Janus MoXTe (X = S, Se) monolayers. • Nonmetallic atom doping can affect the interaction between H and the material surface. • The doping of B and P into the 1T phase of MoSTe, P into the 1T′ phase of MoSTe and MoSeTe can improve the conductivity. [ABSTRACT FROM AUTHOR]

Searching for active and low‐cost electrocatalysts for the hydrogen evolution reaction (HER) is crucial to develop sustainable energy, yet it remains a significant challenge. Based on the density functional theory calculations, a new kind of double atom catalysts (HDACs) with hybrid metal and nonmetal center embedded in g‐CN is reported for the HER. It is demonstrated that the introduction of the nonmetal atoms (B, C, Si, P, and S) near the metal sites enables unique charge communication between them, which offers diatomic center a very different catalytic activity than the single atom counterparts. Out of 130 HDACs, Pd‐B, Ti‐C, Ir‐C, Cr‐Si, Mn‐Si, Co‐Si, Rh‐Si, Au‐Si, Ir‐P, Fe‐S, and Ni‐S pairs are identified as the high‐performance electrocatalysts with nearly ideal adsorption strength for proton. Machine learning analysis allows to directly identify the key characteristics that affect the catalytic activity and establish a predictable framework for a fast screen of the unknown chemical space of HDACs. This work paves a new avenue for designing and developing potential HER catalysts. [ABSTRACT FROM AUTHOR]

Adsorption and advanced oxidation technology are important means to remove organic pollutants, and the combination of adsorption and catalytic degradation to construct a multi-field coupled system can realize valid adsorption and degradation of organic contaminants. In this paper, CuBi 2 O 4 supported by a nonmetallic element-modified graphene hydrogel composite structure CuBi 2 O 4 /X-rGH (X = N, P, S, B) was synthesized and applied to the efficient removal of organic pollutants. We found that the doping of nonmetallic elements enhances the graphene conjugated large π-bond system, which not only improves the adsorption performance of pollutants but also increases the graphene conductivity and builds more carrier transport channels, which is beneficial to the photocatalytic Fenton synergistic degradation activity. Among them, CuBi 2 O 4 /P-rGH could achieve 90 % degradation of phenol (50 ppm) after 20 min of turning on the light, which was nearly 2 times more than the degradation activity of CuBi 2 O 4 /rGH. Electron paramagnetic resonance (EPR) and quenching experiments proved that ·OH was the main active species in the synergistic degradation process, and the mechanism of adsorption of nonmetallic modified graphene hydrogel hybrid catalysts and in situ photocatalytic Fenton degradation of pollutants was proposed. [ABSTRACT FROM AUTHOR]

Molecular iodine is found in many organic synthetic methodologies, both as reagent and as catalyst. Naturally, many groups have carried out computational studies involving this element. However, the choice of computational method proves to be more challenging than for other non‐metals. We quantify herein the errors that some common theory levels can introduce in terms of both structural and energetic deviations. We also evaluate multiple post hoc corrections, namely, vibrational entropy, dispersion, and counter‐poise corrections. Our results indicate the triple‐ζ basis sets are essential to obtain quality results and that post hoc corrections are overall detrimental. [ABSTRACT FROM AUTHOR]

Adsorption and advanced oxidation technology are important means to remove organic pollutants, and the combination of adsorption and catalytic degradation to construct a multi-field coupled system can realize valid adsorption and degradation of organic contaminants. In this paper, CuBi 2 O 4 supported by a nonmetallic element-modified graphene hydrogel composite structure CuBi 2 O 4 /X-rGH (X = N, P, S, B) was synthesized and applied to the efficient removal of organic pollutants. We found that the doping of nonmetallic elements enhances the graphene conjugated large π-bond system, which not only improves the adsorption performance of pollutants but also increases the graphene conductivity and builds more carrier transport channels, which is beneficial to the photocatalytic Fenton synergistic degradation activity. Among them, CuBi 2 O 4 /P-rGH could achieve 90 % degradation of phenol (50 ppm) after 20 min of turning on the light, which was nearly 2 times more than the degradation activity of CuBi 2 O 4 /rGH. Electron paramagnetic resonance (EPR) and quenching experiments proved that ·OH was the main active species in the synergistic degradation process, and the mechanism of adsorption of nonmetallic modified graphene hydrogel hybrid catalysts and in situ photocatalytic Fenton degradation of pollutants was proposed. [ABSTRACT FROM AUTHOR]

Highlights in the field of air analysis included: a new focus on measuring tyre-wear particle emissions; an interest in using unmanned aerial vehicles for sampling purposes and an increased use of ICP-MS for measuring halogenated volatile organics, metals sampled directly from air and single particles. Workers have explored further the full capabilities of ICP-MS/MS, which continued to dominate water analysis, including the speciation analysis of non-metallic elements in environmental samples. By far the largest number of papers on water analysis involved preconcentration. The growing interest in reagents for green chemistry was evidenced by the publication of several reviews. Novelties included the direct introduction of magnetic nanoparticles into FAAS to boost sensitivity, and the simultaneous dual-drop preconcentration of oxidation state species that avoided the need for a sequence of elution steps by preconcentrating the analytes into specific reagents contained in the drops. Although the total reflection XRFS and LIBS techniques are close to achieving the detection limits needed to screen contaminated waters, users of these instruments often neglect to validate their methods adequately through the use of reference materials. In methods for the analysis of soils, plants and related materials, sustainable digestion, extraction and preconcentration methods featured strongly. The development of AAS, AES and AFS methods for the direct analysis of solid samples and for increasing sensitivity through analyte enrichment continued to be of considerable interest. The nitrogen-microwave inductively coupled atmospheric-pressure plasma showed promise for ICP-MS analyses. Applications of LIBS have increased dramatically in number with noteworthy developments including single-chamber laser-ablation LIBS and the analysis of plant leaves without the need for grinding and pelleting. However, many published studies lacked validation through e.g. analysis of CRMs or comparison with results obtained by other techniques. Efforts have continued on the characterisation of natural and synthetic materials that are sufficiently homogeneous to act as reference materials (RMs) in the analysis of geological materials. In particular, application of microanalytical techniques, such as LA-ICP-MS and SIMS, led to the availability of a variety of new RMs for in situ isotope ratio determinations. The application of portable LIBS instrumentation to mineral prospecting and ore processing has received much attention, with the development of new chemometric models to improve data quality. The enormous amount of analytical data produced by modern instrumentation prompted the development of software, most of which has been made freely available, for facilitating the processing and reduction of isotopic data. [ABSTRACT FROM AUTHOR]

The large band gap of La2Ti2O7 has hindered its potential application in photocatalytic water splitting under visible-light irradiation. In this study, we have utilized a passivated approach to tailor the band edges of La2Ti2O7 by combining nonmetals X (X = N and C) with metals M (M = V, Nb, Ta, Mo and W) as dopants to substitute surface O and Ti sites, respectively. The formation energies show that the synthesis of co-doped systems might be easier under O-rich conditions than Ti-rich conditions. The calculated band edges of all the passivated co-doped systems well match with visible light absorption and the oxidation or reduction potential of water. Among them, Mo and W as dopants have more remarkable influence on the narrowing of the band gap and the enhancement of the optical absorption in the visible light region. The hydrogen evolution reaction (HER) on each studied La2Ti2O7 surface is endothermic, and tends to occur on the surface O site far away from the metal dopant. The values of ΔGH suggest that (N+V)-, (2N+Mo)- and (2N+W)-doped systems exhibit higher catalytic activities toward the HER than the pure surface. The active site of the oxygen evolution reaction (OER) is the O site binding to the metal dopant. The difference in the active sites of HER and OER on the co-doped La2Ti2O7 surface is in favor of the separation of photoinduced electrons and holes. Co-doping combinations of (N+Ta), (C+Mo), and (2N+Mo) have comparable and even lower overpotential of OER than the pristine surface. Through the design, we find that (2N+Mo)-doped La2Ti2O7 may become a visible-light-responsive photocatalyst for overall water splitting based on its superior electronic, optical and photocatalytic properties. [ABSTRACT FROM AUTHOR]

The most important structure types of nonmetals belonging to the VIII–IV groups and their importance for the development of the ideas about the composition and structure of the deep shells of the Earth and terrestrial-group planets are analyzed. The structural features of gas hydrates and their possible role in geological processes are considered. The structures of inert gases, hydrogen, and astrophysical ices in the Earth and other planets of the Solar system are presented in the light of new data. The modern concepts of the crystal chemistry of carbon polymorphs, genetic types of diamond, the indicator role of inclusions in its crystals, and conditions of its formation in nature and in model experiments are reviewed. [ABSTRACT FROM AUTHOR]

Agricultural non-point source pollution is increasingly an important issue affecting surface water quality. Currently, the majority of the studies on nitrogen loss have focused on the agricultural field scale, however, the response of surface water quality at the watershed scale into the nitrogen loss at the field scale is poorly understood. The present study systematically reviewed the critical processes and major factors that nitrogen transport from farm fields to surface water bodies. The critical processes of farmland nitrogen entering surface water bodies involve the processes of nitrogen transport from farmland to ditches and the transformation processes of nitrogen during migration in ditches/rivers. Nitrogen transport from farmland to ditches is one of the prerequisites and critical processes for farmland nitrogen transport to surface water bodies. The transformation of nitrogen forms in ditches/rivers is an intermediate process in the migration of nitrogen from farmland to surface water bodies. Nitrogen loss from farmland is related to soil storage and exogenous inputs. Therefore, nitrogen input management should not only consider the current input, but also the contribution of soil storage due to the historical surpluses. Ditches/rivers have a strong retention capacity for nitrogen, which will significantly affect the process of farmland nitrogen entering surface water bodies. The factors affecting nitrogen transformation in river/ditches can be placed in four categories: (1) factors affecting hydraulic retention time, (2) factors affecting contact area, (3) factors affecting biological activity, and (4) forms and amount of nitrogen loading to river/ditches. Ditch systems are more biologically (including plants and microbes) active than rivers with biological factors having a greater influence on nitrogen transformation. When developing pollution prevention and control strategies, ecological ditches can be constructed to increase biological activity and reduce the amount of surplus nitrogen entering the water body. The present research should be valuable for the evaluation of environment impacts of nitrogen loss and the non-point source pollution control. [ABSTRACT FROM AUTHOR]

Disordered rock‐salt (DRS) type active materials are highly significant because of their large reversible capacities, which are due to their unique Li+ diffusion pathway and the redox capabilities of cationic transition metals (TMs) and anionic O ions. Loosely crystalline DRS materials have weak covalent bonds between TMs and O, increasing the O redox contribution and thereby enhancing their capacities. In this study, Mn‐based positive electrode materials with DRS structures are activated and stabilized by mechanochemical doping of nonmetallic elements P and B into interstitial sites. Synthesized Li0.90Mn0.84P0.04O2 (LMPO5) exhibits an initial discharge capacity of 346 mAh g−1 (1050 Wh kg−1) during charging/discharging. Li0.91Mn0.83B0.10O2 (LMBO5) has a moderately expanded lattice size, which facilitates high‐capacity retention during cycling (≈284 mAh g−1 at the 30th cycle). The structural properties of the synthesized active materials are extensively characterized. By introducing nonmetallic elements into the interstitial sites of Mn‐based materials, inexpensive, high‐capacity, and long‐cycling/calendar‐life Co/Ni‐free monometallic positive electrode materials may be further developed. [ABSTRACT FROM AUTHOR]

Electrochemical corrosion has four elements (anode, cathode, a metallic path, and electrolyte). For non-metals, the first three elements are absent. Thus, corrosion is exclusive used for metals and deterioration for non-metals. Microbiologically influenced corrosion (MIC) applies to metals and microbiologically influenced deterioration (MID) applies to non-metals such as polymers and composites. In this article, a four-step algorithm/guide to prepare root cause analysis reports for MIC/MID cases is presented. By applying this algorithm, making syntax errors in such analyses will become as low as possible. [ABSTRACT FROM AUTHOR]

Currently, one of the priority tasks is the development of intelligent materials that are sensitive to stimuli and can be used in catalytic applications for efficient decomposition of organic pollutants. Particularly relevant in this regard is the development of inexpensive non‐metallic hybrid polymer photocatalysts, and the explanation of the mechanism of using light energy in such systems is still the subject of open discussions. In this work, hybrid polymer fiber membranes based on polyvinylidene fluoride (PVDF) with graphite flakes were obtained by electrospinning. The morphology of the obtained samples was investigated using SEM microscopy methods, and their crystalline structure was analysed using XRD, Raman, and FTIR methods. Using RFE spectroscopy, it was shown that the addition of graphite leads to ion‐dipole interaction between the carbon surface and the polymer dipoles, changing the ratio of covalent and semi‐ionic bonds on the surface. The catalytic properties investigated during the decomposition of the organic dye methylene blue (MB) demonstrated high piezocatalytic activity of doped membranes and high photocatalytic activity of PVDF/C0.5. It was established that the photocatalytic activity is due to excitonic excitation. [ABSTRACT FROM AUTHOR]

A difference in encaged non-metallic element (i.e., C2versus O) leads to a clear change of intramolecular interactions and shifts in redox potentials of Lu2C2@C2(13333)-C74 and Lu2O@C2(13333)-C74, as a result of their distinct molecular orbital energy levels. Different from these two endoherals whose HOMOs are located on the cage, experimentally absent Lu2@C2(13333)-C74 possesses a HOMO predominantly delocalized on the internal Lu–Lu bond, accompanied by a much smaller HOMO–LUMO gap, suggesting that the presence of a non-metallic unit broadens the electrochemical gaps and consequently improves the kinetic stability. These findings shed light on the role of non-metallic moieties in clusterfullerenes, providing valuable insights into the stability and properties of metallofullerenes. [ABSTRACT FROM AUTHOR]

In order to make 3D crossbar memory architectures viable, selector elements with highly non-linear current–voltage characteristics are required. Ovonic Threshold Switching (OTS) is a highly non-linear phenomenon observed in amorphous chalcogenides, such as GeSe, that shows promise for application in selectors. In this paper, the impact of alloying with metallic (Zr), metalloid (B, Sb), and non-metallic (C, N) elements as a function of their concentration on the thermal stability and switching properties of alloyed GeSe layers is studied. In the case of the thermal stability analysis, the key parameter that is tracked is the crystallization temperature ( T c) of the as-deposited amorphous films since OTS only occurs in amorphous materials. Using a simple metal–insulator–metal type test structure where the bottom electrode is scaled to 6 μ m, the OTS properties of the alloyed layers are also compared. The pristine leakage current ( I p r i s ), the first fire voltage ( V F F ), and the threshold voltage ( V t h ) were determined using DC and pulsed (AC) measurements. Results indicate that C alloying in combination with sufficiently high nitrogen incorporation can extend the thermal stability above 600 ° C with only low dependence on the C content. Among the metallic and metalloid elements, crystallization temperature is strongly dependent on alloying concentration. In general, larger concentrations are needed to obtain a T c above 400 ° C as compared to CN alloying. Electrical characterization indicates strong dependence of the first fire voltage and the leakage current on the metallicity of the alloying element with only small to moderate concentrations required to influence electrical properties. [ABSTRACT FROM AUTHOR]

The construction of a surface-frustrated Lewis pairs (SFLPs) structure is expected to break the single electronic state restriction of catalytic centers of P-region element materials, due to the existence of acid-base and basic active canters without mutual quenching in the SFLPs system. Herein, we have constructed eight possible SFLPS structures on the In2O3 (110) surface by doping non-metallic elements and investigated their performance as electrocatalytic nitrogen reduction catalysts using density functional theory (DFT) calculations. The results show that P atom doping (P@In2O3) can effectively construct the structure of SFLPs, and the doped P atom and In atom near the vacancy act as Lewis base and acid, respectively. The P@In2O3 catalyst can effectively activate N2 molecules through the enzymatic mechanism with a limiting potential of −0.28 eV and can effectively suppress the hydrogen evolution reaction (HER). Electronic structure analysis also confirmed that the SFLPs site can efficiently capture N2 molecules and activate N≡N bonds through a unique "donation-acceptance" mechanism. [ABSTRACT FROM AUTHOR]

Developing durable and efficient catalysts for the hydrogen evolution reaction (HER) is of great importance for hydrogen production. By judiciously doping nonmetallic elements into transition metal electrocatalysts, the respective electronic configurations of the catalysts can be effectively adjusted, and their activity levels can be improved. Herein, B-doped CoP/nitrogen-doped carbon (B-CoP/NC) was constructed by subjecting B-doped Co-Prussian blue analogue to a phosphidation process. Benefiting from an enhanced electrochemical active area, improved conductivity, and suitable electron distribution caused by the introduction of B, the defective nanocubes of the B-CoP/NC catalyst needed overpotentials of only 158 and 234 mV to achieve current densities of, respectively, 10 and 100 mA cm−2 and showed a low Tafel slope of 67 mV dec−1. This work has supplied a general route involving NaBH4 pretreatment for introducing B into transition metal phosphide and has offered a method for designing HER catalysts. [ABSTRACT FROM AUTHOR]

Ti–6Al–5V titanium alloy was subjected to surface saturation with carbon, nitrogen, and oxygen in order to study the effect of surface modification on its wear resistance and biocompatibility. The alloy was saturated with carbon and nitrogen in low-pressure atmospheres. Oxygenation was carried out by heating the alloy in a solid carburizing agent. The structure and phase state of the grown layers were studied by optical microscopy and X-ray diffraction. General trends in the saturation of the titanium alloy with nonmetals are the formation of a diffusion layer and an increase in the amount of phases based on the α-Ti solid solution, followed by the formation of intermediate phases, such as carbides, nitrides, and oxides differing in stoichiometry, on the surface of the continuous layer. After saturation, the alloy was covered with thin carbide, nitride, and oxide surface layers and had diffusion layers under them. The hardness of the nitrogenated and oxygenated surfaces was 950–1000 HV, and that of the surfaces saturated with carbon was 570 HV. The wear resistance of the alloy was lowest in the as-prepared state and highest after oxygenation. Biocompatibility was assessed from the proliferation of osteoblast-like cells of the MG-63 line. The best biocompatibility was demonstrated by the oxygenated samples, and the biocompatibility of the nitrogenated samples was better than that of the carburized samples. The untreated alloy showed the lowest biocompatibility. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Pd 7 IrP x /NG was fabricated by a facile co-reduction strategy. • The electron-rich interface of Pd 7 IrP x /NG are induced by P-incorporating. • The Pd 7 IrP x /NG reveals prominent electrochemical MOR performance. Incorporating less expensive nonmetal phosphorus (P) into noble metal-based catalysts has become a developing strategy to enhance the catalytic performance of electrocatalysts for methanol electrooxidation reaction (MOR), attributing to the electronic and synergistic structure alteration mechanism. In the work, three-dimensional nitrogen-doped graphene anchoring ternary Pd-Ir-P nanoalloy catalyst (Pd 7 IrP x /NG) was prepared by co-reduction strategy. As a multi-electron system, elemental P adjusts the outer electron structure of Pd and diminishes the particle size of nanocomposites, which heightens the electrocatalytic activity effectively and accelerate MOR kinetics in alkaline medium. The study reveals that the electron effect and ligand effect induced by P atoms on the hydrophilic and electron-rich surface of Pd 7 Ir/NG and Pd 7 IrP x /NG samples can reduce the initial oxidation potential and peak potential of CO ads , showing significantly enhanced the anti-poisoning ability compared with commercial Pd/C as the benchmark. Meanwhile, the stability of Pd 7 IrP x /NG is significantly higher than that of commercial Pd/C. The facile synthetic approach provides an economic option and a new vision for the development of electrocatalysts in MOR. [ABSTRACT FROM AUTHOR]

1. Introduction: Basil (Ocimum basilicum L.), as an annual plant, belongs to the family Lamiaceae, native to Asia (Iran, India, Pakistan, Thailand, etc.) and grows in warm and semi-warm regions. Arsenic (As) is a highly dangerous heavy metal for plants and human. This quasi-metal is widely distributed in the earth's crust, and also is the twentieth most abundant element in the earth's crust. Selenium (Se) is a non-metallic chemical element and also has similarities to arsenic. Global interest in the biological effects of selenium on the environment and the food chain is growing because selenium is essential as a micronutrient for many organisms, including humans and other animals (although it is toxic in high concentrations). Given that arsenic is one of the most important factors limiting crop production in the agricultural sector, it seems necessary to conduct researches in this field to eliminate or reduce the toxic effects of these element on agricultural plants. 2. Materials and Methods: In this study, the effect of selenium on increasing the tolerance rate of basil plant against arsenic heavy metal stress was investigated as a factorial experiment based on completely randomized design under greenhouse condition. The first factor included arsenic-contaminated soil (4576 mg kg-1) and non-contaminated soil, and the second factor included different concentrations of selenium treatment (0, 5 and 10 mg L-1 selenium sodium). Foliar application of selenium was conducted at two stages. The first stage of foliar application was carried out at 4-leaf stage and the second stage of foliar application was done two weeks after the first stage. Leaf number, leaf area, stem height, fresh and dry weight of leaf and stem, chlorophyll and carotenoid content, free proline content, phenol, flavonoid and anthocyanin content, electrolyte leakage and antioxidant enzymes activity were evaluated at the end of the experiment. 3. Results and Discussion: The results showed that arsenic stress negatively affected the morphological traits such as leaf number and area, fresh and dry weight of leaf, fresh and dry weight of stem and plant height, but selenium treatment alleviated the toxicity of arsenic and increased the values of these traits, so that treated plants had higher values of morphological characteristics comparing to control plants under arsenic heavy metal stress. The highest values of morphological traits were observed in plants treated with the highest concentration of selenium (10 mg L-1). In terms of physiological traits, arsenic heavy metal stress reduced the values of some of these traits, so that the lowest amounts of chlorophyll a, chlorophyll b and total chlorophyll, anthocyanin, phenol, and flavonoids were recorded in plants grown in arsenic-contaminated soil without foliar application of selenium. On the other hand, the lowest activity rates of guaiacol peroxidase, catalase and ascorbate peroxidase were observed in plants grown in noncontaminated soil and without selenium foliar application. Also, the both arsenic stress and selenium treatment increased proline accumulation and soluble sugars content of treated plants comparing to control plants. Heavy metal stress increases the production and accumulation of reactive oxygen species (ROS) and damages the membrane structure resulting in more electrolyte leakage. Selenium application led to increasing plant resistance rate against arsenic stress, mainly by enhancing cells antioxidant capacity and osmotic potential. 4. Conclusion: Considering basil is one of the most important aromatic vegetables which has fresh consumption, crispness and wateriness of its leaves and young shoots is one of the most important commercially traits which directly affect crop marketability. Considering arsenic stress has a negative effect on leaf morphological traits (number, area, fresh weight and dry weight) and stem characteristics (fresh weight, dry weight and height), it is recommended to use selenium foliar application as an efficient technique to overcome adverse effects of arsenic stress on basil production in regions with contaminated soils. [ABSTRACT FROM AUTHOR]

In order to break the limitation of plasma nitriding technology, which can only be applied to a few non-metallic gaseous elements, the "double glow discharge phenomenon" was defined and then the "double glow plasma surface metallurgy technology" was invented. This double glow plasma surface metallurgy technology can use any element of the Periodic Table for surface alloying of metallic materials. Countless surface alloys with special physical and chemical properties have been produced on the surfaces of conductive materials. By using the double glow discharge phenomenon, a series of new double glow plasma technologies have been developed to apply to surface metallurgy, graphene technology, brazing, sintering, arc plasma surface alloying, nanotechnology, cleaning, carburizing without hydrogen, and so on. This article briefly introduces the basic principles, functions, and characteristics of each technology. The application prospects and development directions of plasma in metallic materials and the machinery manufacturing industry will also be discussed. [ABSTRACT FROM AUTHOR]

Coal quality analysis is important to promote the rational and sustainable utilization of coal resources. The traditional method of selecting characteristic lines from the coal sample spectrum is time-consuming. This work aims to use laser-induced breakdown spectroscopy (LIBS) to reconstruct principal components (PCs) by utilizing the correlation between full spectrum wave point interpretation variance and calibration values. More components related to the features of interest are obtained and the regression metrics are maximized. Subsequently, quantitative models were established using ordinary least squares (OLS) for ash content, volatile matter, and calorific value. The coefficient of determination (R2) of the training set and test set of ash content and volatile matter was improved from 0.8125 and 0.8222, 0.6502 and 0.6483 to 0.9701 and 0.9818, 0.9458 and 0.9429, respectively. The root-mean-square error of cross-validation (RMSECV) and the root-mean-square error of prediction (RMSEP) were reduced from 1.7843% and 1.7696%, 1.1797% and 1.4301% to 0.7153% and 0.7037%, 0.5678% and 0.6628%, respectively. The training set and test set of calorific value R2 were also improved from 0.7086 and 0.7157 to 0.9857 and 0.9811. RMSECV and RMSEP were reduced from 0.9525 MJ kg−1 and 1.0178 MJ kg−1 to 0.1518 MJ kg−1 and 0.1613 MJ kg−1, respectively. To evaluate the interpretability of PC recombination, the cumulative correlations between ash content, volatile matter, calorific value and the PCs of each wave point in the LIBS spectrum were analyzed, and then the characteristic spectral line locations of the elements that contributed the most to the calibration model were extracted. The results of the analysis of metal and non-metal elements in coal samples show that PC recombination chooses more significant characteristics rather than noise as independent variables. The work demonstrates the feasibility and effectiveness of employing LIBS-based quantitative analysis for rapid coal quality detection in the coal industry. [ABSTRACT FROM AUTHOR]

The current state of research on photocatalytic reforming of organic substances of natural origin using graphite-like carbon nitride, namely its various morphological forms, products of modification by chemical agents, doped with metals and non-metals, nanocomposites with metals and other semiconductors, etc., is considered. Reactions that lead to molecular hydrogen evolution from aqueous solutions of electron-donating organic compounds (lignocellulose, saccharides, alcohols, aldehydes, and acids), processes of simultaneous production of H2 and oxidation of biomass components with the formation of valuable organic substances, as well as reactions of a reduction of several aldehydes of natural origin are analyzed. Possible ways of further research in this photocatalysis branch are outlined. [ABSTRACT FROM AUTHOR]

A wide-gap semiconductor of Yttria (Y2O3) doped with nonmetal elements (B, C, and N) are investigated by using the first-principles method. We mainly discuss the exchange coupling between two dopants and find that the exchange coupling in current cases are sensitive to the B-B, C-C, and N-N distance. Unitary ferromagnetic (FM) and antiferromagnetic (AFM) states have been observed in the two-B-doped and two-N-doped Y2O3 structures, respectively. Surprisingly, as the C-C distance increases, a transformation between FM and AFM has been found, which shows an RKKY-like interaction due to the p-d hybridization between the C dopant and intrinsic Y atoms. [ABSTRACT FROM AUTHOR]

The band gap width has always been the main reason for the low photocatalytic performance of TiO 2 semiconductors. "Band gap engineering" is often used to change the band gap width of TiO 2. On this basis, the impurity band gap was induced below the TiO 2 conduction band by regulating N element. What's interesting was that N element adjusted the valence state of adjacent Ti element and caused the generation of oxygen vacancy. This is due to the extraction of neutral oxygen atoms, resulting in electron transfer to the Ti cation band structure. The 300-N-T catalyst exhibited the best photocatalytic hydrogen production performance under visible light, which was 307.65 μmol/(g·h) and was 61.53 times higher than that of anatase. And the concentration of Ti3+ defects and oxygen vacancy reduced with decreasing of N content in TiO 2. According to Kubelke Munk formula, the band gap of 300-N-T photocatalyst was narrowed to 2.73 eV, which indicated that there are impurity energy levels near the CB and VB of TiO 2 material. The Ti3+ ions as the active site of the photocatalytic reaction was confirmed by instantaneous photocurrent response and EIS characteristic. This study revealed the structure-activity relationship between the content of N element, Ti3+ ions and oxygen vacancy in TiO 2 materials, as well as the decisive process of defect induced visible light catalysis. [Display omitted] • The nonmetallic N element adjusted the valence state of the adjacent Ti element, resulting in the formation of oxygen vacancy. • The forbidden band width of TiO 2 was reduced to 2.73 eV owing to the introduction of N elements. • The structure-activity relationship between N element, Ti3+ ion and oxygen vacancy in TiO 2 material was explored. [ABSTRACT FROM AUTHOR]

The growth of artificial synthesis two-dimensional (2D) materials usually demands for suitable substrate due to their rare bulk allotropies. Borophene, as a typical artificial synthetic material, has been proved its substrate-growth on metal or nonmetals and its high theoretical specific capacity (1720 mAh g−1) for next-genatration electrode material, but structural instability and transfer difficulties have hindered the development of its applications. Here, a structurally stable and freestanding AA-stacked- α ′-4H-borophene sheets have been synthesized by in situ lithium eutectic salt-assisted synthetic method to realize the application of borophene in lithium-ion battery. The atomic structure of AA- α ′-4H-borophene with interlayer VdWs was established by comparing the experimental observation with DFT optimal calculation. Different stacking configurations (AA- and AB-) of borophene was realized by a temperature-structure-photoluminescence intensity relationship, and the AA-stacked borophene exhibits higher specific capacity than AB structure. Based on electrochemical performance, the AA-borophene exhibits excellent rate capability and cycling performance due to its non-collapsible stacking configurations, which dominates great initial coulombic efficiency of 87.3% at 200 mA g−1 superior to that of black phosphorus-based and borophene/graphene. Meanwhile, it still maintains the coulombic efficiency of 99.13% after 1000 cycles. It also shows a reversible capacity of 181 mAh g−1 at 10 mA g−1 between the voltage window of 0.01 and 2 V, which improves the reported capacity (43 mAh g−1) of bulk boron anode by over 430%. This work brings fantastic new view of fabricating stable, stacking and freestanding borophene and provides a significative idea on applications of borophene in energy storage domain. [ABSTRACT FROM AUTHOR]

Transition metal-free half-metallicity recently has been the subject of intense research activity due to its potential in spintronics application. By employing density functional theory calculations, we revealed that F-intercalated GaN bilayers exhibit robust p orbital-based half-metallicity against the intercalant concentration and biaxial strain of −10% to 10%. The stable half-metallicity results from a spontaneous phase transition through Stoner instability and can be attributed to unusually high density of states near the Fermi level due to the quasi-flat bands. These findings provide a strategy to design transition-metal free half-metallic materials for futuristic spintronic applications. [ABSTRACT FROM AUTHOR]

Hydrogen energy is one of the most developing areas of clean energy due to various advantages of hydrogen compared to traditional fossil fuels. One of hydrogen energy electrochemical devices is proton-conducting solid oxide fuel cells. The obtaining of novel highly proton conductive materials is relevant. Nonmetal doping strategy to improve the protonic conductivity in perovskite-related materials is understudied. The phosphorous-doped perovskite CaZr 0.95 P 0.05 O 3.025 was obtained for the first time. The possibility for water uptake was proved by thermogravimetry and mass-spectrometry investigations. It was shown that phosphorous doping led to increase in the conductivity values up to 500 times. The composition CaZr 0.95 P 0.05 O 3.025 demonstrates nearly pure proton transport below 600 °C under wet air. The proton conductivity values are 3.3·10−6 S/cm at 670 °C and 7.6·10−7·S/cm at 500 °C. The nonmetal doping strategy is prospective way to enhance electrical conductivity of proton conductors with perovskite structure. [Display omitted] • Nonmetal doping strategy leads to increase in the protonic conductivity of CaZrO 3. • Phosphorous doping led to increase in the conductivity values up to 500 times. • Phosphorous doping is the promising method for improving protonic conductivity. [ABSTRACT FROM AUTHOR]

We describe the results of using thermal imagers of six types, i.e., having different technical characteristics (with a matrix from to and sensitivity from 25 to 110 mK) in various price segments, for active thermal testing (TT) of delaminations with sizes from to mm located at a depth of 3.1 mm in a test sample of polymethylmethacrylate. The effectiveness of thermal testing was determined with the participation of nine thermograph operators. It is demonstrated that acceptable thermal testing results are possible when using thermal imagers and thermal imaging modules of the low-budget segment. [ABSTRACT FROM AUTHOR]

Context: The property transition between metal and semiconductor is the key to improving the properties of transition metal dichalcogenides (TMDCs). The adsorption of the NbS2 compound in the defect state was adjusted for the first time. The hybrid system overwrites the original surface mechanism of NbS2 and induces indirect band gaps. This modulation mode makes NbS2 convert into a semiconductor and effectively improves the catalytic activity of the material in the system. In addition, the original local magnetic moment of the compound is concentrated in the vacancy region and is improved. The optical properties of the adsorption system indicate that NbS2 compounds can be effectively applied in visible and low-frequency ultraviolet regions. This provides a new idea for the design of the NbS2 compound as a two-dimensional photoelectric material. Methods: In the study, we assume that only one atom is adsorbed on the NbS2 supercell of the defect, and the distance between the two adjacent atoms exceeds 12.74 Å, so the interaction between atoms is ignored in the study. Adsorbed atoms include nonmetallic elements (H, B, C, N, O, F), metallic elements (Fe, Co), and noble metal elements (Pt, Au, Ag). The density functional theory (DFT) was used in the experiment. The non-conservative pseudopotential method was used in the calculation to optimize the crystal structure geometrically. The approximate functional is Heyd-Scuseria-Ernzerhof (HSE06). The calculation method includes the spin-orbit coupling (SOC) effect. The crystal relaxation optimization uses a 7 × 7 × 1 k point grid to calculate niobium disulfide's photoelectric and magnetic properties. A vacuum space of 15Å is introduced in the direction outside the plane, and the free boundary condition is adopted to avoid the interaction between atomic layers. For the convergence parameter setting, the interatomic force of all composite systems is less than 0.03 eV/Å, and the lattice stress is less than 0.05 Gpa. [ABSTRACT FROM AUTHOR]

The progress of this research is the preparation of FeNi alloy thin films by magnetron sputtering. Each step of the experimental process is based on the electrocatalytic performance of the sample, and characterized by many characterizations means such as X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), X-ray energy spectrometry (EDS) and step gauge thickness test for morphology, structure and elemental composition, etc. The analysis of the characterization results is used as a support for the experimental process. Adjustment of various preparation process parameters for material growth and subsequent processing include doping of non-metallic elements and construction of nanostructures. Doping of C elements can make FeNi based alloy films further amorphous. Zn element is used as a pore-forming agent. The two processes of doping and high-temperature vacuum dealloying can make the film obtain a nanoporous structure, which greatly increases the specific surface area. These two strategies reduce the overpotential (η10) of oxygen evolution reaction (OER) of FeNi alloy thin films to 393 mV and 314 mV, which are reduced by 47 mV and 79 mV step by step. The electrochemical properties of the finally obtained alloy film are: overpotential of 314 mV, Tafel slope of 61.8 mV/dec and the stability of only 10% decay at a current density of 10 mA/cm2 for 12 h. In this study, low-cost transition metals were used as the main materials to design OER catalysts, and the catalytic efficiency was comparable to that of commercial noble metal catalysts. The physical preparation methods made each sample have good reproducibility. It provides the experimental basis and theoretical basis for the design and synthesis of new catalytic materials at a higher level. • The electrocatalytic thin films prepared by magnetron sputtering has the characteristics of high stability. • The addition of carbon can deepen the amorphization, thus improving the catalytic efficiency. • High-vacuum dealloying is characterized by high speed and good repeatability in preparing porous structures. [ABSTRACT FROM AUTHOR]