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Nickel‐rich cathode materials have gained popularity in the development of lithium‐ion batteries (LIBs) due to their high energy density, which exceeds 250 Wh kg−1. However, the instability of bulk and surface structures has significantly limited their industrial application. In this study, a three‐in‐one approach to synergistically modulate the structure of LiNi0.83Co0.06Mn0.11O2 (NCM83) from surface to bulk by a phytic acid (PA) coating is proposed. This surface treatment leads to the spontaneous formation of an amorphous lithium phosphates coating layer on the outermost surface, a reconstructed NiO layer at the subsurface, and a gradient P doping in the NCM83 bulk. The resulting hierarchical and multifunctional structure provides a facilitated surface Li‐ion conduction, a NiO‐stabilized subsurface with strong resistance toward side reactions between the electrode and electrolyte, a fast Li ion bulk diffusion endowed by the enlarged LiO6 slab due to the P doping, and an enhanced H2−H3 phase transition reversibility. As a result, the PA‐NCM83 sample exhibits excellent capacity retention with 72.4% after 300 cycles at 1 C within 2.8–4.45 V, and 69.8% after 200 cycles at an elevated temperature of 45 °C. This approach provides a facile and efficient method to stabilize Ni‐rich cathode materials for next‐generation high‐energy LIBs. [ABSTRACT FROM AUTHOR]

As a candidate for a new generation of inexpensive and high‐performance energy storage systems, lithium–sulfur (Li–S) batteries have attracted widespread research. However, the development and application of Li–S batteries are limited by severe polysulfide dissolution and slow reaction kinetics. Herein, a type of ordered mesoporous P‐TiO2−x microsphere with a waxberry‐like shape as the sulfur host material for Li–S batteries is put forward, which combines the radially arranged mesoporous structure with oxygen defects in the mesoporous framework. In addition, the introduction of phosphorus impurities greatly improves the conductivity of the sulfur electrode, enhances electron mobility, and promotes the interaction between the sulfur species and P‐TiO2−x microspheres. Finally, S/P‐TiO2−x cathodes have achieved a high capacity of 1174.9 mAh g−1 at 0.2C and stable cycling (the average capacity attenuation is only 0.086% per cycle at 1C after 600 cycles). [ABSTRACT FROM AUTHOR]

The effect of phosphorus doping in the transition metal germanide Mo5Ge3, which is predicted to be a nodal line semimetal and exhibits superconductivity below Tc = 0.75 K, is studied. It is found that Mo5Ge3−x$_{3-x}$Px retains the tetragonal W5Si3‐type structure up to x = 1.0, and the incorporation of phosphorus leads to a shrinkage of the unit cell volume. Remarkably, Tc of Mo5Ge3−x$_{3-x}$Px is enhanced by more than one order of magnitude with increasing x, reaching 8.24 K at x = 1.0. This enhancement is attributed to the increases in both the density of states at the Fermi level and electron–phonon coupling strength. Theoretical calculations show that the phosphorus doping leads to a nearly rigid‐band shift of the Fermi level into a local maximum of the density of states. This study unveils that transition metal germanides offer an emerging platform to study the interplay between superconductivity and nontrivial band topology. [ABSTRACT FROM AUTHOR]

Improved chloride binding stability for calcium aluminate cements is proposed by the doping of phosphorus. Phosphorus‐modified aluminates clinker has an improved chloride binding stability compared to pristine aluminates, ordinary Portland cement and sulfur‐modified calcium aluminates, as verified by experimental observation. The existence of the newly found phosphorus‐modified Friedel's salt (PFS) accounts for the excellent chloride binding stability, which was understood by density functional theory calculations. Local density of states of the valence band minimum is predominantly localized around P atoms in the PFS, but evenly distributed in the Friedel's salt (FS). The frontier band energy of the partial density of states on Cl and O elements in the PFS is lower than that in the FS by 0.21 and 0.05 eV, respectively. This makes the PFS more stable than the FS salt to ionic attack. [ABSTRACT FROM AUTHOR]

This work investigates the electrooxidation of glycerol in an alkaline environment at non‐doped and P‐doped Pt‐αNi(OH)2 nanoparticles supported on oxidized Vulcan XC‐72R carbon. Pt‐αNi(OH)2 and PtP‐αNi(OH)2 particles with sizes in the range of 3–5 nm were obtained via a one‐step chemical reduction approach. The physicochemical characteristics of the as‐prepared catalysts were studied by inductively coupled plasma‐optical emission spectrometry (ICP‐OES), energy dispersive X‐ray (EDX), X‐ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and x‐ray diffraction (XRD) techniques. It was determined that the incorporation of phosphorus lead to the formation of amorphous PtP‐αNi(OH)2 deposits. TEM analysis showed that the incorporation of phosphorus into the bimetallic Pt‐αNi(OH)2 catalyst origins a remarkable reduction in the average size of the nanoparticles with a narrow size distribution. A substantial improvement in the electrocatalytic properties of the Pt‐αNi(OH)2 system toward the oxidation of glycerol was observed through P doping. The P‐doped electrocatalysts developed a mass current density of 60.3 mA mgPt−1 at 765 mV vs. RHE, which is about 5 and 45 times higher than those of commercial PtRu/C (12.3 mA mgPt−1) and as‐synthesized Pt‐αNi(OH)2/C (1.5 mA mgPt−1), respectively. The temperature‐dependent experiments displayed that the apparent activation energy for the reaction is halved upon the addition of phosphorus. [ABSTRACT FROM AUTHOR]

Requirements for improved catalytic formulations is continuously driving research in hydrotreating (HDT) catalysis for biomass upgrading and heteroatom removal for cleaner fuels. The present work proposes a surface‐science approach for the understanding of the genesis of the active (sulfide) phase in model P‐doped MoS2 hydrotreating catalysts supported on α‐Al2O3 single crystals. This approach allows one to obtain a surface‐dependent insight by varying the crystal orientations of the support. Model phosphorus‐doped catalysts are prepared via spin‐coating of Mo–P precursor solutions onto four α‐Al2O3 crystal orientations, C(0001), A(112‾ 0), M(101‾ 0) and R(11‾ 02) that exhibit different speciations of surface ‐OH. 31P and 95Mo liquid‐state NMR are used to give a comprehensive description of the Mo and P speciation of the phospho‐molybdic precursor solution. The speciation of the deposition solution is then correlated with the genesis of the active MoS2 phase. XPS quantification of the surface P/Mo ratio reveal a surface‐dependent phosphate aggregation driven by the amount of free phosphates in solution. Phosphates aggregation decreases in the following order C(0001)≫M(101‾ 0)>A(112‾ 0), R(11‾ 02). This evolution can be rationalized by an increasing strength of phosphate/surface interactions on the different α‐Al2O3 surface orientations from the C(0001) to the R(11‾ 02) plane. Retardation of the sulfidation with temperature is observed for model catalysts with the highest phosphate dispersion on the surface (A(112‾ 0), R(11‾ 02)), suggesting that phosphorus strongly intervene in the genesis of the active phase through a close intimacy between phosphates and molybdates. The surface P/Mo ratio appears as a key descriptor to quantify this retarding effect. It is proposed that retardation of sulfidation is driven by two effects: i) a chemical inhibition through formation of hardly reducible mixed molybdo‐phosphate structures and ii) a physical inhibition with phosphate clusters inhibiting the growth of MoS2. The surface‐dependent phosphorus doping on model α‐Al2O3 supports can be used as a guide for the rational design of more efficient HDT catalysts on industrial γ‐Al2O3 carrier. [ABSTRACT FROM AUTHOR]

Photoelectrochemical water oxidation by polymeric carbon nitride (PCN) has recently received increasing scientific interest. Herein, phosphorus (P) is doped into PCN (p‐PCN) films through in situ polymerization. p‐PCN sheets are formed and vertically aligned on a conductive substrate, which is used as a photoanode. The optimal photocurrent density of the photoanode is ≈120 μA cm−2, which is more than two times that of the undoped one. The improved performance is accounted as the introduction of P in PCN. On the one hand, P doping increases the valence potential of PCN and improves the ability of water oxidation. On the other hand, charge transfer is improved by extra charges from P. [ABSTRACT FROM AUTHOR]

Molybdenum diselenide (MoSe2), as a member of transitional metal chalcogenides (TMDs), is regarded as a promising electrocatalyst for hydrogen evolution reaction (HER). However, its intrinsic performance is still hampered by insufficient exposure of active sites and inferior electric conductivity. The phase‐engineered synthesis of stable metallic 1T‐MoSe2 with abundant active sites is thus highly desirable for further boosting HER performance. Herein, a phosphorus (P)‐doped MoSe2 with controlled 2H/1T heterophases is synthesized through a facile way. Combining calculations and experiments, it is demonstrated that the doping of P (≈0.83 wt%) not only induces a phase change from 2H to 1T, but activates the Se atoms in the basal plane, thereby significantly enhancing its intrinsic HER performance. An overpotential of 174 mV is achieved at the benchmark of 10 mA cm−2 with a Tafel slope of 51 mV dec−1. More importantly, after the long‐term run at 180 mV for 10 h, the P‐1T/2H‐MoSe2 still displays a high current density of 10.43 mA cm−2 and keeps its original 2H/1T heterostructures, showing superior electrochemical stability and structural robustness. This work provides a facile method for improving the intrinsic HER activity of MoSe2 through nonmetal doping, which helps to understand the activity origin of MoSe2. [ABSTRACT FROM AUTHOR]

Perovskite oxides are promising electrocatalysts for the oxygen evolution reaction (OER). However, the activity and stability of perovskite oxides still needs to be improved to efficiently utilize renewable and clean energy resources. Herein, we selectively introduced phosphorus (P) into SrCo0.8Fe0.2O3‐δ (SCF) to form modified perovskite oxides, i. e., SrCo0.8Fe0.15P0.05O3‐δ, SrCo0.75Fe0.2P0.05O3‐δ and Sr(Co0.8Fe0.2)0.95P0.05O3‐δ. An improved OER activity and stability compared to un‐doped SCF was clearly observed. Meanwhile, the specific surface area, oxygen vacancy content and electronic conductivity increased due to the P doping. Moreover, a lower valence state of B‐site cations induced by the high‐valence P5+ was detected, which may contribute to the better activity and stability. Among them, the dual‐site substitution to form Sr(Co0.8Fe0.2)0.95P0.05O3‐δ stands out when evaluating the activity and stability in alkaline solution. The results suggest that the P doping could be an effective strategy to develop perovskite electrocatalysts with high electrocatalytic activity and stability. A non‐metal element (i. e. phosphorus) has been successfully substituted in perovskite oxides, and the corresponding electrocatalytic activity and stability are greatly enhanced. Among un‐doped SrCo0.8Fe0.2O3‐δ, SrCo0.8Fe0.15P0.05O3‐δ, SrCo0.75Fe0.2P0.05O3‐δ and Sr(Co0.8Fe0.2)0.95P0.05O3‐δ, the dual‐site substituted Sr(Co0.8Fe0.2)0.95P0.05O3‐δ stands out when evaluating the activity and stability of the oxygen evolution reaction in alkaline solution. Via mainly affecting B‐site cations, the high‐valence state of phosphorus (P5+) contributes to the improvement of the electrochemical performance. [ABSTRACT FROM AUTHOR]

Constructing isotype g‐C3N4/g‐C3N4 heterojunction is an approach to improve the efficiency of g‐C3N4 towards solar‐assisted oxidation of water. Such functional configuration can effectively overcome the intrinsic drawback of rapid charge recombination of g‐C3N4. Here, a modified g‐C3N4, with homogeneous phosphorus doping, is prepared in this work through a phosphide‐involved gas phase reaction. The resulting P‐g‐C3N4 displays altered electronic structure, including upshifted band edge potential, narrowed band gap and improved electronic conductivity. These features allow P‐g‐C3N4 as an outstanding candidate to form isotype junction with pristine g‐C3N4. As expected, the accelerated charge separation and migration in target junction is validated by various measurements. The optimized isotype g‐C3N4/P‐g‐C3N4 heterojunction achieves a photocurrent as high as 0.3 mA cm−2 at 1.23 V vs RHE (AM 1.5G, 100 mW cm−2), representing 8‐fold's enhancement compared with pristine g‐C3N4. The present strategy for constructing g‐C3N4‐based isotype heterojunction networks is found effective for large‐scale manufacturing. Isotype photoanode: A phosphorus‐doped g‐C3N4 with suitable electronic structure was explored to construct metal‐free isotype photojunction in large‐scale manufacturing. The percolated networks exhibit largely increased photocurrent than its single component as a result of efficient charge transfer being qualitatively identified. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, phosphorus doped (P doped) multi‐walled carbon nanotubes (CNTs) were prepared and investigated as catalyst for VO2+/VO2+ redox reaction for vanadium redox flow batteries (VRFB). X‐ray photoelectron spectroscopy (XPS) confirms the equable incorporation of P atoms into carbon layers of the CNTs, and that P doping has no obvious effect on the morphologies of the CNTs. The results of cyclic voltammetry and electrochemical impedance spectroscopy indicate that the electrocatalytic properties of the CNTs are significantly enhanced for the VO2+/VO2+ redox couple by P doping. The sample treated at 800 °C (CNTs‐P8) exhibits the highest electrocatalytic activity, with two times higher peak currents for the redox reaction catalyzed by CNTs‐P8 deposited on glassy carbon than for pristine CNTs. A dynamic cell using the CNTs‐P8 catalyst for VO2+/VO2+ redox couple was assembled and the cell performance was evaluated. This cell exhibits better electrochemical properties including higher discharge capacity and energy efficiency, especially at high current density. The average energy efficiency of the cell for 50 cycles increases by 4.2 % at 50 mA cm−2 by using CNTs‐P8. This study demonstrates that the P doped CNTs are an efficient and promising catalyst material for VO2+/VO2+ redox reaction in VRFB systems. [ABSTRACT FROM AUTHOR]

Ultrasonic spray pyrolysis (USP), as an industrially‐scalable synthetic technique used to prepare mesoporous products, has rarely been developed for accessing porous metal carbide hybrids for electrochemical hydrogen evolution reaction (HER). Herein, we report a mesoporous hybrid consisting of tungsten (W)‐doped molybdenum oxide/molybdenum carbide (MoO2/MoC) nanoparticles encapsulated by phosphorus (P)‐doped carbon shells (W‐MoO2/MoC@PC) as an efficient electrocatalyst using this technique. The utilization of SiO2 as a hard template endows W‐MoO2/MoC@PC with a mesoporous structure, and the effective W‐doping further enhances the HER electrocatalytic performance of W‐MoO2/MoC@PC catalyst. As expected, W‐MoO2/MoC@PC shows a low overpotential (η20=208 mV in 0.5 m H2SO4 and 209 mV in 1.0 m KOH for reaching a current density of 20 mA cm−2), and good stability in both acidic and basic electrolyte, which is a promising noble‐metal‐free HER catalyst. Moreover, this facile synthesis strategy is also suitable for preparing other metal‐doped Mo‐based nanocomposites, which can be used in the fields of electrocatalytic water splitting and energy conversion. We report a mesoporous hybrid consisting of W‐doped MoO2/MoC nanoparticles encapsulated by P‐doped carbon shells (W‐MoO2/MoC@PC) as an efficient electrocatalyst. We demonstrate that the mesoporous structure contributes to the superior performance of the hybrid, and the effective W‐doping further enhances the HER performance of W‐MoO2/MoC@PC. [ABSTRACT FROM AUTHOR]

Passivated Emitter and Rear Cells (PERC) are currently being introduced into mass production. The conversion efficiency of industrial p-type PERC cells is limited by the emitter saturation current density of around 90 fA/cm2 of conventional homogeneously POCl3 diffused emitters. In this paper we investigate two alternative emitter formation technologies. The first approach named in-situ oxidation inserts a short thermal oxidation in-between the phosphorus silicate glass deposition and the drive-in of a conventional homogeneous POCl3 diffusion thereby reducing the phosphorus surface concentration. The second approach named Gas Phase Etch Back (GEB) selectively removes around 40 nm of the highly doped surface of the POCl3 diffused emitter by the reactive gas phase of the wet chemical rear polishing bath. Whereas the conventional POCl3 emitter exhibits a phosphorus surface doping concentration of 3 × 1020 cm−3, the in-situ oxidation and the GEB process reduce the doping concentration to 7 × 1019 cm−3 and 4 × 1019 cm−3, respectively. Accordingly, the emitter saturation current density is reduced to excellent values of 22 fA/cm2 ( in-situ oxidation) and 28 fA/cm2 (GEB) compared with 89 fA/cm2 for the reference POCl3 diffusion. Whereas the reference POCl3 emitter limits the PERC conversion efficiency η to 21.1% and the open circuit voltage Voc to 655 mV, the in-situ oxidation improves the PERC current-voltage parameters up to 21.3% and 663 mV. The highest efficiency of 21.6% is obtained with the selective GEB emitter. When solving series resistance issues with the most advanced GEB emitter, the measured Voc and Jsc values would support PERC conversion efficiencies up to 21.9%. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The lattice dynamics and thermoelectric properties of sintered phosphorus-doped nanostructured silicon-germanium alloys obtained by gas-phase synthesis were studied. Measurements of the density of phonon states by inelastic neutron scattering were combined with measurements of the elastic constants and the low-temperature heat capacity. A strong influence of nanostructuring and alloying on the lattice dynamics was observed. The thermoelectric transport properties of samples with different doping as well as samples sintered at different temperature were characterized between room temperature and [ABSTRACT FROM AUTHOR]

Phosphorus-doped hexagonal tubular carbon nitride (P-TCN) with the layered stacking structure was obtained from a hexagonal rod-like single crystal supramolecular precursor (monoclinic, C2/ m). The production process of P-TCN involves two steps: 1) the precursor was prepared by self-assembly of melamine with cyanuric acid from in situ hydrolysis of melamine under phosphorous acid-assisted hydrothermal conditions; 2) the pyrolysis was initiated at the center of precursor under heating, thus giving the hexagonal P-TCN. The tubular structure favors the enhancement of light scattering and active sites. Meanwhile, the introduction of phosphorus leads to a narrow band gap and increased electric conductivity. Thus, the P-TCN exhibited a high hydrogen evolution rate of 67 μmol h−1 (0.1 g catalyst, λ >420 nm) in the presence of sacrificial agents, and an apparent quantum efficiency of 5.68 % at 420 nm, which is better than most of bulk g-C3N4 reported. [ABSTRACT FROM AUTHOR]

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

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

This paper aims at the investigation of the effect of phosphorus doping on the electrochemical properties of ZnO nanorod films as deposited on zinc substrates. Sodium dihydrogen phosphate has been used the phosphorus source for the deposition of ZnO nanorod films with varying electronic and electrochemical properties. Electrochemical impedance spectroscopy based Mott-Schottky analysis was performed to investigate the changes of flat-band potential and donor density. For the films synthesized with the addition of sodium dihydrogen phosphate, a clear reduction in donor densities were observed, which resulted in a decrease of zinc dissolution and oxygen reduction current densities. Octadecylphosphonic acid (ODPA) monolayers could be successfully deposited on the ZnO-film, which led to extremely water repellent surfaces and even more strongly reduced exchange current densities most probably due to an effective reduction in the active electrode surface area. [ABSTRACT FROM AUTHOR]

Results of the studies of plasma–chemical processes in plasma of microwave discharge in gas mixture of hydrogen, methane, and phosphine are presented. For the first time, the dependence of emission intensity of PH radical on the parameters of plasma maintenance is studied in a wide range of variation of gas pressure, microwave power, and phosphine and methane content in gas mixture. Experiments are conducted under conditions that are used in the chemical vapor deposition (CVD) reactors for doping diamond with phosphorus. The relationship between emission intensity of PH radical and efficiency of the incorporation of phosphorus into diamond is analyzed. [ABSTRACT FROM AUTHOR]

Experimental work on phosphorus (P)‐doped cadmium sulfur (CdS) nanowires (NWs) shows unusual n‐type electrical character, its physical origin is not well understood. Here this problem has been addressed by considering possible doping sites (interstitial, anion and cation sites), the distance of the doping site to NW surface, and the influence of dangling bond of host atoms. The P atom favors either a surface cation or a surface anion site, depending on the Cd chemical potential which reflects growth condition. At a surface anion site three p‐type levels appear in the gap. On the other hand, at a surface cation site there is only one shallow n‐type level in the gap, due to the s state of the P atom extending along the surface, as verified by both GGA and rough Meta‐GGA calculations. The physical origin of the n‐type behavior for P‐doped CdS NWs is explained by assuming the P atom adopts the surface cation site, neglecting composite structure P atom forming with intrinsic defects. In this article, a physical explanation is given of why phosphorus‐doped CdS nanowires show unusual n‐type behavior. Calculations indicate that it is due to the phosphorus accumulating on the surface cation site, in this case a n‐type donor level appears in the gap. Neither anion (or interstitial) site doping, nor surface cation dangling bond can cause the n‐type behavior. [ABSTRACT FROM AUTHOR]