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[Display omitted] Lithium metal is deemed a promising anode material for the next-generation batteries with high specific energy. Unfortunately, the growth of Li dendrites and infinite volume change during cycling, caused by the "hostless" feature of metallic Li, have posed a great challenge to the commercialization of Li metal anode. The introduction of appropriate host materials for Li metal is highly desirable. In this work, a N, P dual-doped 3D carbon derived from low-cost quantitative filter paper (NPCQP) is designed and fabricated for direct using as a host for Li metal anode. The resulting NPCQP host achieves a high deposition/stripping Coulombic efficiency of above 97.5 % with a low nucleation overpotential. Moreover, the NPCQP@Li symmetric cells enable an excellent long-term cycling performance (1000 h) with an ultralow voltage hysteresis (12 mV) and stable interface behavior. When paired with the commercial LiFePO 4 cathode, the full cell with NPCQP@Li anode displays impressive long-term cyclic stability and rate capability, outperforming the counter cell with bare Li anode. This contribution sheds light on the rational design of viable host for practical lithium metal anodes. [ABSTRACT FROM AUTHOR]

We propose two techniques to improve the power generating performance of the “thermoelectric power generating paper” based on carbon nanotube (CNT) that we reported in our previous study. First, we remove the excess amount of dispersant (sodium dodecyl sulfate; SDS) in the sample by immersing the sample in nitric acid under a suitable condition (e.g., only SDS is expected to be decomposed and removed, but CNT and pulp are retained), thus improving the conductivity of the paper. Second, we dope the contained CNT in the composite paper by adsorbing KOH and 18-Crown-6 molecule physically so that it exhibits an n-type characteristic. In thermoelectric power generation, a large electromotive force can generally be obtained by combining p-type and n-type semiconductors. The semiconducting CNT is known to exhibit a p-type property normally because of O2 adsorption in the air, so we tried to make an n-type semiconducting paper. As a result, we succeeded in obtaining the n-type semiconducting paper, and the paper maintained the property for at least 45 days. Finally, we multi-staged the modified paper for a demonstration of power generation and measured the performance. The results showed that the multi-staged thermoelectric power generating paper had up to 10.0 mV of electromotive force and 0.31 mA of short-circuit current. This unique thermoelectric power generating paper has great potential for use in daily life by combining it with existing products made from paper.

Along with the developing of flexible electronics, there is a strong interest in high performance flexible energy storage materials. As natural carbohydrate polymer, cellulose fibers have potential applications in the area due to their biodegradability and flexibility. However, their conductive and electrochemical properties are impossible to meet the demands of practical applications. In this study, cellulose fibers were combined with polyaniline to develop novel paper-based supercapacitor electrode material. Cellulose fibers were firstly coordinated to Cu(II) and subsequently involved in polymerization of polyaniline. Not only the mass loading of polyaniline was significantly increased, but also an impressive area specific capacitance (2767 mF/cm2 at 1 mA/cm2) was achieved. The developed strategy is efficient, environmentally friendly, and has implications for the development of cellulosic paper-based advanced functional materials. [Display omitted] [ABSTRACT FROM AUTHOR]

Development and application of a new, simple, inexpensive, and eco-friendly method is presented for the quantification of bumetanide in human urine samples for the detection of doping in sports. The method involves the use of a paper platform and digital image detection and is based on the reaction between bumetanide, p -dimethylaminocinnamaldehyde (p -DAC), and HCl in a methanolic medium, yielding a colored compound in a delimited area on a qualitative filter paper. The concentrations of p- DAC and HCl were optimized by a chemometric experimental design. After the addition of the reagents to the paper, digital images were obtained by scanning in a multifunctional printer and analyzed using the RGB pattern. The linear bumetanide concentration range was 6.90 × 10−5–1.37 × 10−3 mol L−1 with R 2 = 0.993 and the limits of detection (LOD) and quantification (LOQ) were 3.60 × 10−4 and 1.09 × 10−4 mol L−1, respectively. A SPE clean-up step for the samples were required to eliminate the interference of urinary urea. The recoveries obtained varied from 94% to 105%, indicating the absence of significant matrix effects or interferences in urine samples after clean-up step. The proposed method was successfully applied to the analysis of bumetanide in human urine samples. • Spot test employing a paper platform delimited with hydrophobic barriers • μPAD associated with digital image detection for bumetanide determination • Determination of bumetanide in urine samples for doping sports • The method represents an advantageous alternative to most of the reported methods. [ABSTRACT FROM AUTHOR]

In the long-term operation of power transformer, the traditional cellulose insulation paper undergoes aging phenomena, making it difficult for this type of paper to meet severe insulation requirements. In this study, cellulose is modified by doping with melamine-grafted nano-SiO2, and cellulose/water (C-H2O), nano-SiO2-modified cellulose/water (CN-H2O) and melamine-grafted nano-SiO2-modified cellulose/water (CAN-H2O) models are developed. The results show that the mechanical properties of CN-H2O and CAN-H2O are improved relative to those of C-H2O and that CAN-H2O exhibits the best mechanical properties. Furthermore, the glass transition temperatures of CN-H2O and CAN-H2O are, respectively, 39 and 69 K, higher than that of C-H2O. Near the glass transition temperature, the mean square displacement of the water molecules changes considerably. Therefore, increasing the glass transition temperature and thus the thermal stability of cellulose can be achieved by modifying cellulose with melamine-grafted SiO2 nanoparticles. Experimental studies show that with an increase in the aging time, the moisture content in the modified insulation paper will be less than that in the unmodified insulation paper, while the tensile strength, degree of polymerization (DP) and breakdown strength were greater than that in the unmodified insulation paper. In particular, the melamine-grafted nano-SiO2-modified insulation paper has the lowest moisture content and highest tensile strength DP and breakdown strength during the entire aging time. Thus, this study shows that the thermal stability and electrical characteristics of the melamine-grafted nano-SiO2-modified insulation paper is the highest at both the microscopic and macroscopic levels, indicating that this insulation paper could meet the insulation performance requirements of large transformers under high-temperature and high-pressure conditions. [ABSTRACT FROM AUTHOR]

Self‐standing two‐dimensional P‐doped molybdenum diselenide (MoSe2) nanosheets were synthesized on carbon fiber paper (CFP) (P‐doped MoSe2/CFP) using a hydrothermal reaction followed by phosphorization and were subsequently used as a high‐efficiency hydrogen evolution reaction (HER) electrocatalyst. Nanosheet aggregation was remarkably inhibited, and numerous active sites were exposed. The H adsorption and desorption capacities of MoSe2 were optimized by doping P atoms in the MoSe2 lattice. Electrochemical testing indicated that the overpotential (η50) required by P‐doped MoSe2/CFP was only 186 mV, which was much lower than that of the as‐prepared MoSe2/CFP (237 mV). The Tafel slope of P‐doped MoSe2/CFP was 54.3 mV ⋅ dec−1, which was remarkably lower than that of the as‐prepared MoSe2/CFP (79.8 mV ⋅ dec−1). The Gibbs energy of the H atoms adsorbed on P‐doped MoSe2 (ΔGH*) reached the lowest value (0.202 eV) when the hydrogen coverage (θH) was 75 %. For MoSe2, the lowest ΔGH* value was 0.296 eV when θH was 25 %. The adsorption and desorption of H atoms at the active sites of P‐doped MoSe2 occurred easier than at the active sites of MoSe2. Moreover, the P doping effect facilitated the formation of more Hads species during the Volmer reaction and substantially accelerated the kinetics of the HER. [ABSTRACT FROM AUTHOR]

Abstract Exploring new materials and methods to achieve high utilization of sulfur with lean electrolyte is still a common concern in lithium‐sulfur batteries. Here, high‐density oxygen doping chemistry is introduced for making highly conducting, chemically stable sulfides with a much higher affinity to lithium polysulfides. It is found that doping large amounts of oxygen into NiCo2S4 is feasible and can make it outperform the pristine oxides and natively oxidized sulfides. Taking the advantages of high conductivity, chemical stability, the introduced large Li–O interactions, and activated Co (Ni) facets for catalyzing Sn2–, the NiCo2(O–S)4 is able to accelerate the Li2S‐S8 redox kinetics. Specifically, lithium‐sulfur batteries using free‐standing NiCo2(O–S)4 paper and interlayer exhibit the highest capacity of 8.68 mAh cm–2 at 1.0 mA cm–2 even with a sulfur loading of 8.75 mg cm–2 and lean electrolyte of 3.8 µL g–1. The high‐density oxygen doping chemistry can be also applied to other metal compounds, suggesting a potential way for developing more powerful catalysts towards high performance of Li–S batteries.

M-doped TiO2 and mixed oxides M xO y-TiO2 (M = V, Bi, W) were synthesized by the reactive mineralization of ash-free filter paper under anhydrous conditions. Mixtures of metal chlorides (TiCl4 with VOCl3, WCl6, or BiCl3) were reacted directly with cellulose, and three different Ti/M atomic ratios were used (99, 19, and 9). The resulting materials consist of original nanoflower assemblies of needle-shaped primary particles. Their physicochemical characteristics were investigated by various techniques (X-ray diffraction, diffuse-reflectance UV/Vis spectroscopy, electron microscopy, and elemental analysis). The incorporation of the doping metal or the formation of mixture of oxides with TiO2 (WO3, Bi2O3) depends on the metal and the proportions used. The photocatalytic activities of the materials were tested for the degradation of phenol. The vanadium-doped materials exhibit true solid-solution formation and their band gaps shift into the visible range. [ABSTRACT FROM AUTHOR]

Promising approaches to improve electrical characteristics, chemical resistance, and thermal stability of the resistivity of ZnO‐based TCO thin films are investigated. The following ways were tested: a) gradient doping of ZnO grains into the synthesized TCO films by indium in order to create passivating coatings on the surface of the grains; b) preventing the oxygen diffusion into the films by suppressing the columnar structures formation; c) methods combining the above ones. It was found that in the ZnO‐based TCO films deposited by magnetron sputtering at temperature above 150°C under the presence of excess zinc in the reagent flow, a decrease in the porosity of the columnar ZnO films is observed after subsequent heat treatments in air. The introducing of In, Ga, Sn metals to the composition of the ZnO films contributes to the formation of thin surface oxide sub‐layers with passivation properties on the surface of the ZnO grains. The results of research clearly show that preventing the formation of a columnar structure in combination with the passivation of grain surfaces creates real prospects for expanding the areas of application of ZnO‐based transparent electrodes. [ABSTRACT FROM AUTHOR]

Promising approaches to improve electrical characteristics, chemical resistance, and thermal stability of the resistivity of ZnO‐based TCO thin films are investigated. The following ways were tested: a) gradient doping of ZnO grains into the synthesized TCO films by indium in order to create passivating coatings on the surface of the grains; b) preventing the oxygen diffusion into the films by suppressing the columnar structures formation; c) methods combining the above ones. It was found that in the ZnO‐based TCO films deposited by magnetron sputtering at temperature above 150°C under the presence of excess zinc in the reagent flow, a decrease in the porosity of the columnar ZnO films is observed after subsequent heat treatments in air. The introducing of In, Ga, Sn metals to the composition of the ZnO films contributes to the formation of thin surface oxide sub‐layers with passivation properties on the surface of the ZnO grains. The results of research clearly show that preventing the formation of a columnar structure in combination with the passivation of grain surfaces creates real prospects for expanding the areas of application of ZnO‐based transparent electrodes. [ABSTRACT FROM AUTHOR]

Stories pervade sport. In elite spectator sport, stories play out in packed stadiums while being broadcast simultaneously to immense TV audiences. These stories, which present controversial goals, great comebacks, underdog victories, or clever instances of cheating among other incidents, can foster moral reflection. This paper explores the relationship between sport, stories, and morality. It discusses Richard Rorty's insistence on narrative as a powerful vehicle to moral change and progress, as one way to understand this relationship. Stories about Justin Gatlin and Therese Johaug – two world-class athletes who tested positive for prohibited substances and served doping bans – are discussed as exemplars of redescriptive narratives: stories that can foster our moral imagination, broaden our conversations and help us to enhance our descriptions and practices of solidarity. In this Rortyan approach, moral progress can occur when the work of narrative redescription joins forces with philosophy's rational struggle for coherence. Building on this conception of progress, the paper concludes with a reflection on narrative redescription as a method in sport ethics. [ABSTRACT FROM AUTHOR]

Exploring new materials and methods to achieve high utilization of sulfur with lean electrolyte is still a common concern in lithium‐sulfur batteries. Here, high‐density oxygen doping chemistry is introduced for making highly conducting, chemically stable sulfides with a much higher affinity to lithium polysulfides. It is found that doping large amounts of oxygen into NiCo2S4 is feasible and can make it outperform the pristine oxides and natively oxidized sulfides. Taking the advantages of high conductivity, chemical stability, the introduced large Li–O interactions, and activated Co (Ni) facets for catalyzing Sn2–, the NiCo2(O–S)4 is able to accelerate the Li2S‐S8 redox kinetics. Specifically, lithium‐sulfur batteries using free‐standing NiCo2(O–S)4 paper and interlayer exhibit the highest capacity of 8.68 mAh cm–2 at 1.0 mA cm–2 even with a sulfur loading of 8.75 mg cm–2 and lean electrolyte of 3.8 µL g–1. The high‐density oxygen doping chemistry can be also applied to other metal compounds, suggesting a potential way for developing more powerful catalysts towards high performance of Li–S batteries. [ABSTRACT FROM AUTHOR]

Sport doping is not a recent phenomenon. Athletes have used many forms of performance enhancements going back to antiquity. Within the sport philosophy literature, sport doping is entangled in a multitude of ethical discourses, some denouncing, and some supporting, doping in sport. Our aim is to use a systematic approach to classify ethical discourses put forward by scholars focused on doping. To take stock of these ethical discourses, and to advance the sport philosophy literature on doping, this paper provides an empirical account of the types of arguments used in the peer-reviewed sport philosophy literature. This empirical account is intended to provide a map of the ethical discourses in circulation, to highlight the most common arguments, and to show where other types of arguments are absent or less well developed. To map the ethical discourses, the authors use an ethical discourse typology from a university-based ethical reasoning program. [ABSTRACT FROM AUTHOR]

In part I of this paper, we developed physical insights into the role and impact of acceptor and donor traps—resulting from C-doping in GaN buffer—on avalanche breakdown in AlGaN/GaN HEMT devices. It was found that the donor traps are mandatory to explain the breakdown voltage improvement. In this paper, silicon doping is proposed and explored as an alternative to independently engineer donor trap concentration and profile. Keeping in mind the acceptor and donor trap relative concentration requirement for achieving higher breakdown buffer, as depicted in part I of this paper, silicon & carbon codoping of GaN buffer is proposed and explored in this paper. The proposed improvement in breakdown voltage is supported by physical insight into the avalanche phenomena and role of acceptor/donor traps. GaN buffer design parameters and their impact on breakdown voltage as well as leakage current are presented. Finally, a modified Si-doping profile in the GaN buffer is proposed to lower the C-doping concentration near GaN channel to mitigate the adverse effects of acceptor traps in GaN buffer. [ABSTRACT FROM AUTHOR]

In this paper, the effect of C, N and O atom doping of intrinsic MoSe2 on the adsorption capacity of Ni is investigated based on first-principle research methods. The aim is to analyze whether intrinsic MoSe2 can be doped and modified to improve its adsorption capacity of Ni so that it can be used as a new type of adsorbent material. By calculating and analyzing the energy band structure, density of states, differential charge and optical properties of each system, the conclusions are as follows: the O-doped MoSe2 system has the best adsorption capacity for Ni, and the adsorption capacities of the three systems are in the following order: O>N>C. The bandgap value of intrinsic MoSe2 adsorbed Ni-atom decreases, while the Fermi energy level of the C-doped MoSe2 adsorbed Ni-atom system is located in the valence band, which shows p-type doping. The differential charge of the system was analyzed and the charge transfer of the adsorbed system was increased by C, N and O atom doping, and the O-doped system had the strongest adsorption capacity for Ni. It was shown that the charge distribution between the system and the adsorbed Ni-atom changed considerably after atomic doping, and the bonds between the Ni-atom and the dopant atoms of the C-, N- and O-doped adsorption system were strongly ionic. Optical analysis reveals that C, N and O atom doping improves the charge binding ability of Ni-adsorbed MoSe2 material, which gives it a higher polarization rate and faster electric field response. The absorption of ultraviolet light is greatly enhanced, which can improve the efficiency of solar cells and convert solar energy into electricity more effectively. Overall, the Ni adsorption capacity of atomically doped MoSe2 is improved, indicating that doping can be an effective means to improve the adsorption of Ni-atom by intrinsic MoSe2. It is hoped that the research results in this paper can provide some theoretical guidance for the application of MoSe2 in optoelectronic devices. [ABSTRACT FROM AUTHOR]

In this paper, the effect of doping and nanostructuring on the electrostatic potential across the electrochemical interface between a transition metal oxide and a water electrolyte is investigated by means of the Poisson–Boltzmann model. For spherical nanoparticles and nanorods, compact expressions for the limiting potentials at which the space charge layer includes the whole semiconductor are reported. We provide a quantitative analysis of the distribution of the potential drop between the solid and the liquid and show that the relative importance changes with doping. It is usually assumed that high doping improves charge dynamics in the semiconductor but reduces the width of the space charge layer. However, nanostructuring counterbalances the latter negative effect; we show quantitatively that in highly doped nanoparticles the space charge layer can occupy a similar volume fraction as in low-doped microparticles. Moreover, as shown by some recent experiments, under conditions of high doping the electric fields in the Helmholtz layer can be as high as 100 mV/Å, comparable to electric fields inducing freezing in water. This work provides a systematic quantitative framework for understanding the effects of doping and nanostructuring on electrochemical interfaces, and suggests that it is necessary to better characterize the interface at the atomistic level. [ABSTRACT FROM AUTHOR]

Context: In this paper, we systematically studied the effects of non-metallic element (B, C, N, O, F) doping and biaxial stretching on the photoelectric properties of ZrS2/ZrSe2 heterostructures by using the first-principles calculation method based on density functional theory. The results show that the p-type doping is realized by B, C, and N atom doping, and the n-type doping is realized by O and F atom doping. The doping of B and C atoms produces impurity energy levels in the band gap, which affects the conductivity of the heterostructure. The band gap of N and O atom–doped heterostructures increases under tensile strain, but it is still a direct band gap. The analysis of the optical properties of the heterostructures shows that the doping of non-metallic atoms can adjust the optical absorption rate and reflectivity of the heterostructures. Under the action of tensile strain, the optical properties of the doped heterostructures have changed significantly in the low-energy region. This article provides a theoretical basis for the future application of ZrS2/ZrSe2 heterostructures. Method: This paper uses the first-principles calculation method based on density functional theory. The PBE exchange-correlation functional based on generalized gradient approximation (GGA) is selected for the specific calculation, and the crystal structure is geometrically optimized by the ultrasoft pseudopotential method. It is verified that when the cutoff energy of the ZrS2/ZrSe2 heterostructure is 500 eV, the K-point grid is selected to be 10 × 10 × 2 with the lowest energy, so the cutoff energy is selected to be 500 eV. The K-point grid is selected to be 10 × 10 × 2. The convergence limits for structural optimization are as follows: the maximum force between atoms is 0.01 eV/Å, the convergence threshold of the maximum energy change is set to 10−9 eV/atom, and the convergence threshold of the maximum displacement is 0.001 Å. In order to avoid the influence of atomic periodic motion between different atomic layers, a vacuum layer of 20 Å is added in the vertical direction. Considering the interaction of vdW between the interfaces, the DFT-D2 method is used to verify. The optical properties were calculated by the random phase approximation method, and the K-point grid was selected as 12 × 12 × 2. [ABSTRACT FROM AUTHOR]

The thermal stability of the γ-Fe2O3@SiO2 nanocomposites and super low friction of the γ-Fe2O3@SiO2 nanocomposite coatings in ambient air at high temperature are investigated in this paper. X-ray diffraction, scanning electron microcopy, transmission scanning electron microcopy, high-temperature tribometer, thermogravimetric analysis and differential scanning calorimetry were used to investigate the microstructure, surface morphology and high-temperature tribological properties of the γ-Fe2O3@SiO2 nanocomposite coatings, respectively. The results show that the γ-Fe2O3@SiO2 nanocomposite with the core–shell structure has excellent thermal stability because the SiO2 shell inhibits the phase transition of the γ-Fe2O3 phase to the α-Fe2O3 phase in the nanocomposites. The temperature of the phase transition in γ-Fe2O3 can be increased from 460 to 829 °C. The γ-Fe2O3@SiO2 nanocomposite coatings exhibit super low friction (0.05) at 500 °C. A high-temperature super low friction mechanism is attributed to γ-Fe2O3 and the tribochemical reactions during sliding. [ABSTRACT FROM AUTHOR]

By N2O/N2/O2 doped the active layer and He/Ar/Al/SiNx doped the S/D of Top‐Gate IGZO TFT, we have summarized the effects of different doping modes on the properties of Top‐Gate IGZO TFT, including doping the active layer of Top‐Gate IGZO TFT with N2O can obviously improve the electrical uniformity of devices , and doping the S/D of Top‐Gate IGZO TFT with aluminum(Al) can significantly improve the NBTIS/ PBTIS of devices, etc. By optimizing the doping method, we have fabricated a device with both good electrical uniformity and good electrical properties, with threshold voltage shift (ΔVth) of 18 points less than 1V, Mobility=8.6 cm2/V.S,Subthreshold Swing(SS) =0.26 V/dec ,Threshold Voltage （Vth） =2.9V ,ΔVth=1.54 V (NBTIS, Bias=‐30V,T=80 ℃ ,Backlight=4500Nit,2000S,W/L=6/12), ΔVth= 5.28V(PBTIS,Bias=+30V ， T=80 ℃ ,Backlight=4500Nit, 2000S， W/L=6/12). [ABSTRACT FROM AUTHOR]

The World Anti-Doping Code (2021) includes a substance on the prohibited list if it meets at least two of the following: (1) it has the potential to enhance or enhances sport performance; (2) it represents an actual or potential health risk to the athlete; (3) it violates the spirit of sport. This paper uses a case study to illustrate points of tension between this code and enhancements that are appropriate to ban; we argue that there are banned drugs (e.g., acetazolamide and dexamethasone) the use of which we have good reason to not only permit but encourage for high-altitude sports. Drawing on lessons from this case study, we propose a reformulation of the Code that requires (1–3) be met but offers preferable ways of unpacking conditions (1) and (3) – and in a way that better preserves how the spirit of sport condition should be indexed to particular sports. Our formulation is inclusive enough to rule in drugs like acetazolamide and dexamethasone as permissible in high-altitude sports while at the same time ruling out problem cases – including many drugs already on the prohibited list. The result is an attempted alignment between the conditions specified and those drugs that should be banned. [ABSTRACT FROM AUTHOR]