Pillar effect induced by ultrahigh phosphorous/nitrogen doping enables graphene/MXene film with excellent cycling stability for alkali metal ion storage

Graphene's large theoretical surface area and high conductivity make it an attractive anode material for potassium-ion batteries(PIBs).However,its practical application is hindered by small interlayer distance and long ion transfer distance.Herein,this paper aims to address the issue by introducing MXene through a simple and scalable method for assembling graphene and realizing ultrahigh P doping content.The findings reveal that MXene and P-C bonds have a "pillar effect" on the structure of graphene,and the P-C bond plays a primary role.In addition,N/P co-doping introduces abundant defects,providing more active sites for K^(+) storage and facilitating K^(+) adsorption.As expected,the developed ultrahigh phosphorous/nitrogen co-doped flexible reduced graphene oxide/MXene(NPrGM) electrode exhibits remarkable reversible discharge capacity(554 mA hg^(-1) at 0.05 A g^(-1)),impressive rate capability(178 mA h g^(-1) at 2 A g^(-1)),and robust cyclic stability(0.0005% decay per cycle after 10,000 cycles at 2 A g^(-1)).Furthermore,the assembled activated carbon‖NPrGM potassium-ion hybrid capacitor(PIHC) can deliver an impressive energy density of 131 W h kg^(-1) and stable cycling performance with 98.1% capacitance retention after5000 cycles at 1 A g^(-1).Such a new strategy will effectively promote the practical application of graphene materials in PIBs/PIHCs and open new avenues for the scalable development of flexible films based on two-dimensional materials for potential applications in energy storage,thermal interface,and electromagnetic shielding.

Research on the Low-carbon Cementitious Materials:Effect of Triisopropanolamine on the Hydration of Phosphorous Slag and Steel Slag

Cement,phosphorous slag(PS),and steel slag(SS)were used to prepare low-carbon cementitious materials,and triisopropanolamine(TIPA)was used to improve the mechanical properties by controlling the hydration process.The experimental results show that,by using 0.06%TIPA,the compressive strength of cement containing 60%PS or 60%SS could be enhanced by 12%or 18%at 28 d.The presence of TIPA significantly affected the hydration process of PS and SS in cement.In the early stage,TIPA accelerated the dissolution of Al in PS,and the formation of carboaluminate hydrate was facilitated,which could induce the hydration;TIPA promoted the dissolution of Fe in SS,and the formation of Fe-monocarbonate,which was precipitated on the surface of SS,resulting in the postponement of hydration,especially for the high SS content.In the later stage,under the continuous solubilization effect of TIPA,the hydration of PS and SS could refine the pore structure.It was noted that compared with portland cement,the carbon emissions of cement-PS-TIPA and cement-SS-TIPA was reduced by 52%and 49%,respectively.

Direct observation of the distribution of impurity in phosphorous/boron co-doped Si nanocrystals

Doping in Si nanocrystals is an interesting topic and directly studying the distribution of dopants in phosphorous/boron co-doping is an important issue facing the scientific community.In this study,atom probe tomography is performed to study the structures and distribution of impurity in phosphorous/boron co-doped Si nanocrystals/SiO_(2) multilayers.Compared with phosphorous singly doped Si nanocrystals,it is interesting to find that the concentration of phosphorous in co-doped samples can be significantly improved.Theoretical simulation suggests that phosphorous-boron pairs are formed in co-doped Si nanocrystals with the lowest formation energy,which also reduces the formation energy of phosphorous in Si nanocrystals.The results indicate that co-doping can promote the entry of phosphorous impurities into the near-surface and inner sites of Si nanocrystals,which provides an interesting way to regulate the electronic and optical properties of Si nanocrystals such as the observed enhancement of conductivity and sub-band light emission.

Properties of Self-recoverable Mechanoluminescence Phosphor Ca_(5)Ga_(6)O_(14)∶Eu^(3+) and Its Information Encryption Application

A novel self-recoverable mechanoluminescent phosphor Ca_(5)Ga_(6)O_(14)∶Eu^(3+) was developed by the high-tem-perature solid-state reaction method,and its luminescence properties were investigated.Ca_(5)Ga_(6)O_(14)∶Eu^(3+)can produce red mechanoluminescence,and importantly,it shows good repeatability.The mechanoluminescence of Ca_(5)Ga_(6)O_(14)∶Eu^(3+) results from the piezoelectric field generated inside the material under stress,rather than the charge carriers stored in the traps,which can be confirmed by the multiple cycles of mechanoluminescence tests and heat treatment tests.The mechanoluminescence color can be turned from red to green by co-doping varied concentrations of Tb^(3+),which may be meaningful for encrypted letter writing.The encryption scheme for secure communication was devised by harnessing mechanoluminescence patterns in diverse shapes and ASCII codes,which shows good encryption performance.The results suggest that the mechanoluminescence phosphor Ca_(5)Ga_(6)O_(14)∶Eu^(3+),Tb^(3+)may be applied to the optical information encryption.

Structural and Luminescent Properties of Mg_(0.25-x)Al_(2.57)O_(3.79)N_(0.21):xMn^(2+)Green-Emitting Transparent Ceramic Phosphor

A series of spinel-type Mg_(0.25-x)Al_(2.57)O_(3.79)N_(0.21):xMn^(2+)(MgAlON:xMn^(2+))phosphors were synthesized by the solid-state reaction route.The transparent ceramic phosphors were fabricated by pressureless sintering followed by hot-isostatic pressing(HIP).The crystal structure,luminescence and mechanical properties of the samples were systematically investigated.The transparent ceramic phosphors with tetrahedrally coordinated Mn^(2+)show strong green emission centered around 515 nm under blue light excitation.As the Mn^(2+)concentration increases,the crystal lattice expands slightly,resulting in a variation of crystal field and a slight red-shift of green emission peak.Six weak absorption peaks in the transmittance spectra originate from the spin-forbidden ^(4)T_(1)(^(4)G)→^(6)A_(1) transition of Mn^(2+).The decay time was found to decrease from 5.66 to 5.16 ms with the Mn^(2+)concentration.The present study contributes to the systematic understanding of crystal structure and properties of MgAlON:xMn^(2+)green-emitting transparent ceramic phosphor which has a potential application in high-power light-emitting diodes.

Achieving Narrowed Bandgaps and Blue-Light Excitability in Zero-Dimensional Hybrid Metal Halide Phosphors via Introducing Cation-Cation Bonding

Zero-dimensional(0D)hybrid metal halides,which consist of organic cations and isolated inorganic metal halide anions,have emerged as phosphors with efficient broadband emissions.However,these materials generally have too wide bandgaps and thus cannot be excited by blue light,which hinders their applications for efficient white light-emitting diodes(WLEDs).The key to achieving a blue-light-excitable 0D hybrid metal halide phosphor is to reduce the fundamental bandgap by rational chemical design.In this work,we report two designed hybrid copper(I)iodides,(Ph_(3)MeP)_(2)Cu_(4)I_(6)and(Cy_(3)MeP)_(2)Cu_(4)I_(6),as blue-light-excitable yellow phosphors with ultrabroadband emission.In these compounds,the[Cu_(4)I_(6)]^(2-)anion forms an I6 octahedron centered on a cationic Cu_(4)tetrahedron.The strong cation-cation bonding within the unique cationic Cu_(4)tetrahedra enables significantly lowered conduction band minimums and thus narrowed bandgaps,as compared to other reported hybrid copper(I)iodides.The ultrabroadband emission is attributed to the coexistence of free and self-trapped excitons.The WLED using the[Cu_(4)I_(6)]^(2-)anion-based single phosphor shows warm white light emission,with a high luminous efficiency of 65 Im W^(-1)and a high color rendering index of 88.This work provides strategies to design narrow-bandgap 0D hybrid metal halides and presents two first examples of blue-light-excitable 0D hybrid metal halide phosphors for efficient WLEDs.

Fabrication of YAG:Ce^(3+) and YAG:Ce^(3+),Sc^(3+) Phosphors by Spark Plasma Sintering Technique

In this study,a single-doped phosphors yttrium aluminum garnet(Y_(3)Al_(5)O_(12),YAG):Ce^(3+),single-doped YAG:Sc^(3+),and double-doped phosphors YAG:Ce^(3+),Sc^(3+) were prepared by spark plasma sintering(SPS)(lower than 1 200℃).The characteristics of synthesized phosphors were determined using scanning electron microscopy(SEM),X-ray diffraction(XRD),and fluorescence spectroscopy.During SPS,the lattice structure of YAG was maintained by the added Ce^(3+) and Sc^(3+).The emission wavelength of YAG:Ce^(3+) prepared from SPS(425-700 nm) was wider compared to that of YAG:Ce^(3+) prepared from high-temperature solid-state reaction(HSSR)(500-700 nm).The incorporation of low-dose Sc^(3+) in YAG:Ce^(3+) moved the emission peak towards the short wavelength.

Durable hierarchical phosphorus‐doped biphase MoS_(2)electrocatalysts with enhanced H^(*)adsorption

Phase engineering is an efficient strategy for enhancing the kinetics of electrocatalytic reactions.Herein,phase engineering was employed to prepare high‐performance phosphorous‐doped biphase(1T/2H)MoS_(2)(P‐BMS)nanoflakes for hydrogen evolution reaction(HER).The doping of MoS_(2)with P atoms modifies its electronic structure and optimizes its electrocatalytic reaction kinetics,which significantly enhances its electrical conductivity and structural stability,which are verified by various characterization tools,including X‐ray photoelectron spectroscopy,high‐resolution transmission electron microscopy,X‐ray absorption near‐edge spectroscopy,and extended X‐ray absorption fine structure.Moreover,the hierarchically formed flakes of P‐BMS provide numerous catalytic surface‐active sites,which remarkably enhance its HER activity.The optimized P‐BMS electrocatalysts exhibit low overpotentials(60 and 72 mV at 10 mA cm^(−2))in H_(2)SO_(4)(0.5 M)and KOH(1.0 M),respectively.The mechanism of improving the HER activity of the material was systematically studied using density functional theory calculations and various electrochemical characterization techniques.This study has shown that phase engineering is a promising strategy for enhancing the H*adsorption of metal sulfides.

The KEu(WO_(4))_(2)Red Phosphor Co-doped with Li^(+)and SO_(4)^(2-)for Synergistic Enhancement of High Efficiency and Thermal Stability

A series of tungstate red phosphors K_(1-x)Li_(x)Eu(WO_(4))_(2-y)(SO_(4))_(y)were successfully prepared by sol-gel method,and the effects of the introduction of Li~+and SO_(4)^(2-)on the fluorescence intensity and thermal quenching properties of the prepared K_(1-x)Li_(x)Eu(WO_(4))_(2-y)(SO_(4))_(y)phosphors were investigated.The X-ray diffraction data show that the prepared(Li^(+)and SO_(4)^(2-))-doped KEu(WO_(4))_(2)phosphors have a monoclinic tetragonal structure.In addition,the emission intensities of all the observed emission peaks change significantly with the increase of Li~+doping concentration,especially the intensity of the emission peaks at 615 nm fluctuated significantly and reached the maximum at x=0.3 and y=0.2.The K_(1-x)Li_(x)Eu(WO_(4))_(2-y)(SO_(4))_(y)phosphors are found to have the highest fluorescence intensity at x=0.3 and y=0.2.Moreover,the K_(0.7)Li_(0.3)Eu(WO_(4))_(1.8)(SO_(4))_(0.2)phosphor has better thermal quenching properties and luminescence efficiency,and the experimental results indicates that the fluorescence intensity and thermal burst performance of KEu(WO_(4))_(2)red phosphor could be effectively improved by using low-cost bionic doping of Li^(+)and SO_(4)^(2-).

Synthesis and Luminescence Improvement of CaAlSiN_(3) Phosphors Doped with Eu^(2+) and Mn^(2+) for White LEDs

Eu^(2+) and Mn^(2+) co-activated CaAlSiN_(3) red phosphors were produced using the solid-state reaction tech⁃nique in a N2 environment.Excitation spectra,emission spectra,and diffuse reflection spectra were used to study the luminescence characteristics,energy gap,and thermal stability in detail.CaAlSiN_(3)∶Eu^(2+) exhibits an extended emission band when stimulated with 450 nm blue light,which is caused by the 4f65d to 4f7 transition of Eu^(2+).Similar⁃ly,CaAlSiN_(3)∶Mn^(2+) displays a wide emission band centered at 628 nm,which results from Mn^(2+)’s transition from 4T1(4G) to 6A1(6S).When the ions of Mn^(2+)were combined into CaAlSiN_(3)∶Eu^(2+),the photoluminescence intensity of Eu^(2+ )was greatly boosted because there was energy transfer and co-emission between Mn^(2+) and Eu^(2+).Beyond that,CaAlSiN_(3)∶Eu^(2+),Mn^(2+) emerges with splendid thermostability and high quantum efficiency,the quenching temperature surpasses 300℃,and the internal quantum efficiency is determined to be around 84.9%.The white LED was pack⁃aged with a combination of CaAlSiN_(3)∶Eu^(2+),Mn^(2+),LuAG∶Ce3+ and a blue chip.At a warm white-light corresponding color temperature(3009 K) with CIE coordinates(0.4223,0.3748),the color rendering index Ra has reached 93.2.CaAlSiN_(3)∶Eu^(2+),Mn^(2+) would have great application potential as a red-emitting phosphor for white LEDs.

Mechanism of phosphorus removal in beneficiation of high phosphorous oolitic hematite by direct reduction roasting with dephosphorization agent

High phosphorous oolitic hematite ore is one of typical intractable iron ores in China, and the conventional beneficiation methods are found to be impracticable to , remove phosphorus from the ore effectively. Better beneficiation index were gotten by direct reduction roasting with dephosphorization agent followed by two stages of grinding and magnetic separation. P content decreases from 0.82% in the raw ore to 0.06% in the magnetic concentrate, and the total iron grade increases from 43.65% to 90.23%, the recovery of iron can reach 87%. Mechanisms of phosphorus removal in the beneficiation of high phosphorous oolitic hematite ore by direct reduction roasting with dephosphorization agent were studied using XRD, SEM and EPMA. The results showed that about 20% of the apatite in the raw ore transferred into phosphorus and volatilized with the gas in the process of reduction roasting, while the rest 80% apatite was not involved in the reaction of generation of phosphorus, and remained as apatite in the roasted products, which was removed to tailings by grinding and magnetic separation. A small amount of phosphorus existed in the magnetic concentrate as apatite. The oolitic texture of raw ore was partly changed during roasting, resulting in the formation of nepheline in the reaction between the dephosphorization agent, SiO2 and Al2O3 in the raw ore, which greatly improved the liberation degree of minerals in the roasted products, and it was beneficial to the subsequent grinding and magnetic separation.

Denitrifying phosphorous removal in anaerobic/anoxic SBR system with different startup operation mode

To achieve stable and efficient nitrogen and phosphorus removal and to investigate the characteristics of the A/A SBR enriched with denitrifying phosphorus removal bacteria(DPB),the whole course of startup was studied with two reactors operated in different mode.The reactor I was operated under anaerobic/settling/anoxic/settling mode,and the reactor II was operated under anaerobic/anoxic/settling mode.Differences between the two reactors in removal efficiency of COD,nitrogen and phosphorus were examined.The results indicated that efficient performance could be achieved in both reactors with different startup operation mode,while the phosphorus removal efficiency was improved sooner in reactor I than in reactor II,which suggested that reactor I would supply a more favorable condition for DPB proliferation.Meanwhile,it was observed that the amount of organic substrates consumption had a linear correlation to that of phosphorus release in anaerobic phase when DPB was accumulated in the A/A SBR denitrifying phosphorus removal system.

Researches on the Treatment of Phosphorous Wastewater with Oyster Shells

Based on the analysis of adsorptive features of oyster shells,the researches on the treatment of phosphorous wastewater with oyster shells and the effect of temperature on phosphorus removal were carried out.XRD was used to characterize the crystalline phases,and the main component of oyster shells was shown to be CaCO3.When the pretreatment temperature reached 800 ℃,some CaCO3 decomposed into CaO.As the temperature was further raised,CaO increased gradually.Via SEM testing,the oyster shell was a kind of natural porous materials.The pore wall partially collapsed from 550 to 900 ℃.No obvious porous structure was found at 900 ℃.However,without preheating,the oyster shell phosphorous removal material can not adsorb the phosphorus.Pretreatment made calcium activate,thus greatly increasing the absorption of phosphorus.

Separation of Indium and Iron from Dilute Sulphate Solutions with a Phosphorous Mixer Extractant

The phosphorous mixer introduced could replace D2EHPA as an extractant applied in the extraction of indium. The extraction properties of the phosphorous mixer were studied. The influences of extractant concentration, organic/aqueous (O/A) phase ratio, equilibrium time, and pH value of the feed solutions on the extraction of indium, and separation of indium-iron were investigated experimentally. Under the best operating conditions, more than 98% of indium. was extracted through two-stage counter-current extraction. The optimizing condition of indium extraction is determined as follows: O/A = 1 : (9-12) in volume ratio; 30% PPD in sulphonated kerosene; pH of the feed, about 0.6; equilibrium time, 3-5 min. The extractant has good reusing and anti-aging properties.

A Blended Cement Containing Blast Furnace Slag and Phosphorous Slag

Blended cement containing blast furnace slag (BFS) and phosphorous slag( PS) is a new kind of cement. The total content of blended materials could increase if two additives were used. Using the same admixtures , the properties of the blended cement with 70% additives could reach the standard of 525-grade slag cement according to GB. The strength of cement with 80% additives could reach the standard of 425-grade slag cement. The tests of strength, pore structure, hydration products, inhibiting alkali-aggregate reaction, resistance to sulfate corrosion of BFS-PSC were performed.

Effects of Fermentation Product Containing Phytase on Productive Performance,Egg Quality,and Phosphorous Apparent Metabolism of Laying Hens Fed Different Levels of Phosphorus

This study investigated the effects of fermentation product containing phytase （FPP） that was fermented using waste vinegar residue （WVR） as substrate from Aspergillusficuum NTG-23 on productive performance, egg quality, and phosphorus apparent metabolism of laying hens. First, 375 22-wk-old Jinghong hens were allocated into 5 treatments （5 replicates of 15 hens each） in an 8-wk experiment for evaluating the parameters of productive performance, egg quality, serum, and tibia. Experimental diets contained 4% FPP and 96% corn-soybean diet. The levels of dicalciurn phosphate （DCP） were 1.34, 1.01, 0.67, 0.34 and 0%. Next, thirty 31-wk-old Jinghong hens were fed 5 types of diets for evaluating phosphorous apparent metabolism rate. Egg productive rate, egg weight, feed conversion ratio, Haugh unit, egg albumen height, serum calcium, tibia ash, tibia ash calcium and tibia breaking strength were not different significantly among 5 treatments. The significant difference of average daily feed intake was not appeared when the DCP content of corn-soybean-FPP diet was reduced to 0.67%; the eggshell hardness, eggshell thickness and serum phosphorus were not reduced significantly until the DCP content of corn-soybean-FPP diet was reduced to 0.34%. The yolk color was improved when the laying hens fed deficient DCP corn-soybean-FPP diet. A 22.14% reduction in excreta phosphorus was observed when the laying hens fed low phosphorus （0.67% DCP） corn-soybean-FPP diet. A 30% elevation of phosphorus apparent metabolism rate was obtained when the DCP content of corn-soybean-FPP diet was decreased from 1.34 to 1.01%. The reducing cost of layer diet was totalized about 120 CNY 1000 kg1 diet when the content of DCP was 0.67% in corn-soybean-FPP diet. These results indicated that FPP could be applied in laying hen as a potential, cost-effective and rational application of WVR.

Comparison of Phosphorous Absorption, Quality and Yield Between High Oil Corn and Common Corn as Influenced by Phosphorous Application

A field trial was carried out to investigate phosphorous (P) absorption, grain quality and yield between high oil corn and common corn. The results indicated that high oil corn var.Tongyou 1 obtained lower highest P absorption rate (HAR) and later occurring date of HAR, in comparison with common corn var. Simi 25. The highest HAR and the earliest occurring date of HAR was obtained by the treatments of P45 and P75 in Tongyou 1 and Simi 25 separately; while the total amount of P accumulated by maize plant was achieved by P105 treatment in both varieties. P in grain relied mainly on root uptake at maturation that accounted for 85.7-96.8% and 79.3-84.3% for Tongyou 1 and Simi 25, respectively. Tongyou 1 contained more oil and protein contents, but less starch content with lower grain yield. P application at appropriate rate enhanced contents of protein and fatty acid, but the increment of starch content was neglectable. Acknowledgements This study was financed by the National Key Tech- nologies R & D Program (2004BA520A13), P.R.China.

Ecological stoichiometry of nitrogen, phosphorous, and sulfur in China's forests

Much attention has been paid to the stoichiometry of carbon(C), nitrogen(N), and phosphorus(P) because of their significance for plant growth and climate change. However, other nutrients, such as sulfur(S), are often ignored. In this study, we analyzed the stoichiometry of N, P, and S in leaves of 348 plant species in China's forests. The results show higher N content and higher molar ratios of N/P and P/S in Angiospermae than in Gymnospermae. At the family level, Ulmaceae absorbed more N and P from soils than other families, and Cupressaceae absorbed more S than other families. In addition,except for bamboo and other tropical forests, leaf N and P content of China's forests generally increased from low to middle latitudes and then slightly decreased or plateaued at high latitudes. Plant ecotypes, taxonomic groups, environmental conditions, atmospheric S precipitation, and soil-available N and P significantly affected the distribution and stoichiometry of leaf N, P, and S in China's forests.Our study indicates that China's forests are likely limited by P and S deficiencies which may increase in the future.

Phosphorous Forms in Sediments and Their Distribution in the Yangtze Estuary and Coastal Areas

Based on analyses of surface and core sediments in the tidal flats of the Yangtze Estuary and coastal areas, the present study reveals phosphorous forms existing in sediments and their distributions. The results show that phosphorus in tidal flat sediments in the study area mainly consists of inorganic phosphorous forms, involving DP, Fe-P, Al-P, and Ca-P and organic phosphorous forms, in which Ca-P and OP are dominant compositions. This finding indicates that spatial distributions of various phosphorous forms are related to sedimentary environments in water and grain sizes of sediments, and are influenced by sewage discharges and effluents from aquacultivation in the coastal areas.

Effect of Organic and Inorganic Phosphorous on Growth of Roselle(Hibiscus sabdariffa L.)

To investigate the performance of organic and inorganic phosphorous on growth of Roselle （Hibiscus sabdariffa L.）, an experiment was carried out at Newly Developmental Farm （NDF）, Horticulture Section, the university of Agriculture Peshawar, Pakistan, during 2012. The experiment was laid out in a Randomized Complete Block Design （RCBD） with split plot arrangement and replicated three times. The chemical fertilizer Single Super Phosphate （SSP） was used as inorganic source of phosphorus, while Organic Phosphate （OP） from organic product produced by Niha corporation containing 20% organic mineralized P205, was used as the source of organic phosphorous. Both the sources of fertilizer were applied at the rate of 10, 20, 30 40 and 50 kg. hm2 and control. The statistical analysis of data revealed that both the sources and levels of phosphorus significantly affected most of the growth parameters of Roselle except germination percentage and survival percentage. Plant height （112.09 era）, numbers of leave plant1 （177.87）, numbers of branch plant1 （4.08）, leaf areas （126.60 cm2）, days to flowering （142.83）, fresh flower weight （2.56 g）, fresh calyx weight （1.70 g）, dry calyx weight （0.43 g）, numbers of calyces （94.10）, numbers of root plant-1 （11.03）, root length （22.67 cm） and root weight （27.50 g） were observed in plants fertilized with organic source of phosphorous. Phosphorous levels significantly affected all of the parameters except germination percentage and survival percentage. The maximum plant height （124.39 cm）, numbers of branches （5.32）, numbers of leave plantl （204.89）, leaf areas （148.14 cm2）, fresh flower weight （3.32 g）, fresh calyx weight （2.04 g）, dry calyx weight （0.51 g）, numbers of calyces （105.30）, numbers of root plant-1 （12.78）, root length （24.50 cm） and root weight （29.94 g） were observed in plants fertilized with 40 kg. hm-2 phosphorous and the maximum numbers of days to flowering （148.17） were observed in the control plants. It was concluded from the experimental results that organic phosphorous at the rate 40 kg. hm2 would be used for better production of Roselle under agro-climatic condition of Peshawar.