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Abstract: 5-[o-(4-Bromine amyloxy)phenyl]-10,15,20-triphenylporphrin (o-BrPETPP) was electropolymerized on a glassy carbon electrode (GCE), and the electrocatalytic properties of the prepared film electrode response to dopamine (DA) oxidation were investigated. A stable o-BrPETPP film was formed on the GCE under ultrasonic irradiation through a potentiodynamic process in 0.1M H2SO4 between −1.1V and 2.2V versus a saturated calomel electrode (SCE) at a scan rate of 0.1Vs−1. The film electrode showed high selectivity for DA in the presence of ascorbic acid (AA) and uric acid (UA), and a 6-fold greater sensitivity to DA than that of the bare GCE. In the 0.05molL−1 phosphate buffer (pH 6.0), there was a linear relationship between the oxidation current and the concentration of DA solution in the range of 5×10−7 molL−1 to 3×10−5 molL−1. The electrode had a detection limit of 6.0×10−8 molL−1(S/N=3) when the differential pulse voltammetric (DPV) method was used. In addition, the charge transfer rate constant k =0.0703cms−1, the transfer coefficient α =0.709, the electron number involved in the rate determining step n α =0.952, and the diffusion coefficient D o =3.54 10−5 cm2 s−1 were determined. The o-BrPETPP film electrode provides high stability, sensitivity, and selectivity for DA oxidation. [Copyright &y& Elsevier]

Abstract: A novel process for the recovery of metal values from a mixture of spent lithium-ion batteries (LIBs) and nickel-metal hydride (NiMH) batteries is presented. The iron shells of spent batteries were firstly dismantled using a specially designed dismantling machine. Then after the separation of aluminum substrate and electrolyte and the subsequent heating treatment, iron shells and metal-mesh substrate in the dismantled substances were effectively separated with a sieve. The powder residues including LiCoO2, copper oxides, metal nickel and hydrogen storage alloy and their oxides were dissolved using 3 mol L−1 H2SO4 +3 wt.% H2O2 at 70 °C, S/L=1:15 for 5 h. Finally, rare earths (RE) were precipitated as sodium RE double sulfate, copper was extracted as CuSO4 with 10 wt.% Acorga M5640 at pH=1.5–1.7, cobalt and nickel were extracted as their sulfates with 1 M Cyanex272 at pH=5.1–5.3 and 6.3–6.5, respectively. The experimental results showed that the recovery exceeded 94% for all metal values. [Copyright &y& Elsevier]

Abstract: The oxide films of nickel electrode formed in 30wt.% KOH solution under potentiodynamic conditions were characterized by means of electrochemical, in situ PhotoElectrochemistry Measurement (PEM) and Confocal Microprobe Raman spectroscopic techniques. The results showed that a composite oxide film was produced on nickel electrode, in which aroused cathodic or anodic photocurrent depending upon polarization potentials. The cathodic photocurrent at −0.8V was raised from the amorphous film containing nickel hydroxide and nickel monoxide, and mainly attributed to the formation of NiO through the separation of the cavity and electron when laser light irradiates nickel electrode. With the potential increasing to more positive values, Ni3O4 and high-valence nickel oxides with the structure of NiO2 were formed successively. The composite film formed in positive potential aroused anodic photocurrent from 0.33V. The anodic photocurrent was attributed the formation of oxygen through the cavity reaction with hydroxyl on solution interface. In addition, it is demonstrated that the reduction resultants of high-valence nickel oxides were amorphous, and the oxide film could not be reduced completely. A stable oxide film could be gradually formed on the surface of nickel electrode with the cycling and aging in 30wt.% KOH solution. [Copyright &y& Elsevier]

Abstract: A novel process to reclaim spent zinc manganese dioxide batteries (SDBs) through synthesizing Zn–Mn ferrite magnetic materials is present. Firstly, the dismantling, watering, magnetism, baking and griddling steps were consecutively carried out to obtain iron battery shells, zinc grains and manganese compounds using the collected SDBs, and then these separated substances were dissolved with 4molL−1 H2SO4 to prepare FeSO4, ZnSO4 and MnSO4 reactant solutions. Secondly, Zn–Mn ferrites with stoichiometric ratio of Mn0.26Zn0.24FeO2 were synthesized using chemical co precipitation process with ammonium oxalate precipitator. The XRD results showed that the obtained Zn–Mn ferrites had spinel structure and high purity at the calcining temperatures of 850–1250°C. With the increase of calcining temperature, the finer crystalline structure could be formed, and their intensity of saturation magnetization reached the highest value at 1150°C. The magnetization performances of Zn–Mn ferrites prepared from the SDBs were similar to that of from analysis reagents, suggesting the feasibility to synthesize Zn–Mn ferrites with high properties from SDBs. [Copyright &y& Elsevier]

Abstract: This paper describes a new recycling process of metal values from spent lithium-ion batteries (LIBs). After the dismantling of the spent batteries steel crusts, the leaching of battery internal substances with alkaline solution and the dissolving of the residues with H2SO4 solution were carried out. Then mass cobalt was chemically deposited as oxalate, and Acorga M5640 and Cyanex272 extracted the small quantities of copper and cobalt, respectively. Lithium was recovered as deposition of lithium carbonate. It is shown that about 90% cobalt was deposited as oxalate with less than 0.5% impurities, and Acorga M5640 and Cyanex272 were efficient and selective for the extraction of copper and cobalt in sulfate solution. Over 98% of the copper and 97% of the cobalt was recovered in the given process. In addition, the waste solution was treated innocuously, and LiCoO2 positive electrode material with good electrochemical performance was also synthesized by using the recovered compounds of cobalt and lithium as precursors. The process is feasible for the recycling of spent LIBs in scale-up. [Copyright &y& Elsevier]

Tungsten phosphide (WP) nanoparticles supported on nitrogen and phosphorus co-doped carbon nanosheets (WP@NPC) provide outstanding performance as a multifunctional separator in lithium-sulfur batteries, enabling higher sulfur utilization and exceptional rate capability. Its excellent performance is associated with the abundance of lithium polysulfide (LiPS) adsorption and catalytic conversion sites and swift ion transport within the separator. Key to these features is the sulfophilic character of W and the lithiophilicity of nitrogen and phosphorus, as well as the capability of WP to regulate the LiPS catalytic conversion, accelerating the Li-S redox kinetics. [Display omitted] Lithium-sulfur batteries (LSBs) hold great potential as future energy storage technology, but their widespread application is hampered by the slow polysulfide conversion kinetics and the sulfur loss during cycling. In this study, we detail a one-step approach to growing tungsten phosphide (WP) nanoparticles on the surface of nitrogen and phosphorus co-doped carbon nanosheets (WP@NPC). We further demonstrate that this material provides outstanding performance as a multifunctional separator in LSBs, enabling higher sulfur utilization and exceptional rate performance. These excellent properties are associated with the abundance of lithium polysulfide (LiPS) adsorption and catalytic conversion sites and rapid ion transport capabilities. Experimental data and density functional theory calculations demonstrate tungsten to have a sulfophilic character while nitrogen and phosphorus provide lithiophilic sites that prevent the loss of LiPSs. Furthermore, WP regulates the LiPS catalytic conversion, accelerating the Li-S redox kinetics. As a result, LSBs containing a polypropylene separator coated with a WP@NPC layer show capacities close to 1500 mAh/g at 0.1C and coulombic efficiencies above 99.5 % at 3C. Batteries with high sulfur loading, 4.9 mg cm−2, are further produced to validate their superior cycling stability. Overall, this work demonstrates the use of multifunctional separators as an effective strategy to promote LSB performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel Bi 4 O 5 Br 2 SCNs with over 85% {10–1} facets exposure and O defects were synthesized. • Bi 4 O 5 Br 2 SCNs exhibits excellent photocatalytic toluene oxidation activity under blue light. • The yield of benzaldehyde is 1876.66 μmol g−1 h−1, 21 times higher than the comparative sample. • Studies indicate that the O-deficient Bi 4 O 5 Br 2 {10–1} facets have exceptional adsorption for O 2. • The interaction between •O 2 – and the benzyl H initiates the activation of the C(sp3)-H bonds. Reactive radicals are crucial for activating inert and low-polarity C(sp3)-H bonds for the fabrication of high value-added products. Herein, novel single-crystal oxygen-rich bismuth oxybromide nanosheets (Bi 4 O 5 Br 2 SCNs) with more than 85 % {10–1} facets exposure and oxygen defects were synthesized via a facile solvothermal route. The Bi 4 O 5 Br 2 SCNs demonstrated excellent photocatalytic performance in the selective oxidation of toluene under blue light. The yield of benzaldehyde was 1876.66 μmol g−1 h−1, with a selectivity of approximately 90 %. Compared to that of polycrystalline Bi 4 O 5 Br 2 nanosheets (Bi 4 O 5 Br 2 PCNs), the activity of Bi 4 O 5 Br 2 SCNs exhibit a 21-fold increase. Experimental studies and density functional theory (DFT) calculations have demonstrated that the defect Bi 4 O 5 Br 2 (10–1) facets exhibits exceptional adsorption properties for O 2 molecules. In addition, the single-crystal structure in the presence of surface defects significantly increases the separation and transport of photogenerated carriers, resulting in the effective activation of adsorbed O 2 into superoxide radicals (•O 2 –). Subsequently, the positively charged phenylmethyl H is readily linked to the negatively charged superoxide radical anion, thereby activating the C H bond. This study offers a fresh perspective and valuable insights into the development of efficient molecular oxygen-activated photocatalysts and their application in the selective catalytic conversion of aromatic C(sp3)-H bonds. [ABSTRACT FROM AUTHOR]

A sodium bis(fluorosulfonyl)imide (NaFSI)‐based multifunctional electrolyte is developed by partially replacing NaPF6 salt in the electrolyte to improve the wide temperature range working capability of NaNi1/3Fe1/3Mn1/3O2/hard carbon (NNFM111/HC) sodium‐ion batteries (SIBs). The capacity retention of the SIBs with NaFSI‐NaPF6 dual salt electrolyte increases from 47.2 % to 75.5 % after 250 cycles at 25 °C, and from 51.0 % to 82.3 % after 80 cycles at 45 °C, and the 1 C discharge capacity retention at the low temperature of −20 °C also increases 26.8 %. In the single salt system, NaPF6 effectively passivate the aluminum foil and NaFSI passivate the electrode/electrolyte interface. The synergistic effect of NaPF6 and NaFSI greatly improves the battery performance in a wide temperature range. This NaFSI‐based dual salt electrolyte also effectively overcomes the flaws when the SIBs using NaFSI or NaPF6 independently, and makes it more suitable for SIBs, indicating promising prospects in the commercial application of NNFM111/HC SIBs. [ABSTRACT FROM AUTHOR]

The lithium‐ion batteries (LIBs) with high nickel cathode have high specific energy, but as the nickel content in the cathode active material increases, batteries are suffering from temperature limitations, unstable performance, and transition metal dissolution during long cycling. In this work, a functional electrolyte with P‐phenyl diisothiocyanate (PDITC) additive is developed to stabilize the performance of LiNi0.8Co0.1Mn0.1O2 (NCM811)/graphite LIBs over a wide temperature range. Compared to the batteries without the additive, the capacity retention of the batteries with PDITC‐containing electrolyte increases from 23 % to 74 % after 1400 cycles at 25 °C, and from 15 % to 85 % after 300 cycles at 45 °C. After being stored at 60 °C, the capacity retention rate and capacity recovery rate of the battery are also improved. In addition, the PDITC‐containing battery has a higher discharge capacity at −20 °C, and the capacity retention rate increases from 79 % to 90 % after 500 cycles at 0 °C. Both theoretical calculations and spectroscopic results demonstrate that PDITC is involved in constructing a dense interphase, inhibiting the decomposition of the electrolyte and reducing the interfacial impedance. The application of PDITC provides a new strategy to improve the wide‐temperature performance of the NCM811/graphite LIBs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hard carbon in the PC/EC-based electrolyte can achieve excellent cycle performance and rate performance for sodium-ion batteries. • For the first time, the differences of the ion solvation/desolvation behavior in the electrolytes are proposed to uncover the underlying mechanisms of the distinct electrochemical performance of HC in the PC/EC-based electrolyte and the PC-based electrolyte. • A SEI film with a higher percentage of organic composition is formed in the PC/EC-based electrolyte. • The PC/EC-based electrolyte exhibits a faster ion desolvation process compared to the PC-based electrolyte. Although hard carbon in propylene carbonate / ethylene carbonate (PC/EC)–based electrolytes possesses favorable electrochemical characteristics in rechargeable sodium–ion batteries, the underlying mechanism is still vague. Numerous hypotheses have been proposed to solve the puzzle, but none of them have satisfactorily unraveled the reason at the molecular–level. In this study, we firstly attempted to address this mystery through a profound insight into the disparity of the ion solvation/desolvation behavior in electrolyte. Combining the results of density functional theory (DFT) calculations and experiments, the work explains that compared to the sole PC–based electrolyte, Na+–EC 4 molecules in the PC/EC–based electrolyte preferentially undergo reduction and contribute to the emergence of a more stable protective film on the surface of hard carbon, leading to the preferable durability and rate capability of the cell. Nevertheless, applying the ion solvation/desolvation model, it also reveals that Na+–(solvent) n molecules in the PC/EC–based electrolyte can achieve faster Na+ desolvation processes than in the PC–based electrolyte alone, contributing to the enhancement of charge transfer kinetics. This research holds great importance in uncovering the possible mechanism of the remarkable electrochemical– properties of hard carbon in PC/EC–based electrolytes, and advancing its practical utilization in future sodium–ion batteries. [ABSTRACT FROM AUTHOR]

Lithium–sulfur batteries (LSBs) have emerged as one of the ideal contenders for the upcoming generation of high energy storage devices due to their superb energy density. Nonetheless, the shuttle effect generated by intermediate lithium polysulfides (LiPSs) during cell cycling brings about capacity degradation and poor cycling stability of LSBs. Here, a versatile SrFe12O19 (FSO) and acetylene black (AB) modified PP separator is first presented to inhibit the shuttle effect. Thanks to the strong chemical interaction of Fe and Sr with polysulphides in FSO, it can trap LiPSs and provide catalytic sites for their conversion. Therefore, the cell using the FSO/AB@PP separator has a high initial discharge specific capacity (930 mA h g−1) at 2 C and lasts for 1000 cycles with a remarkably low fading rate (0.036% per cycle), while those using PE and AB@PP separators have inferior initial specific capacities (255 mA h g−1 and 652 mA h g−1, respectively) and fail within 600 cycles. This work proposes a novel approach for addressing the shuttle of LiPSs from a bimetallic oxide modified separator. [ABSTRACT FROM AUTHOR]

Organic electrode materials bring about new possibilities for the next generation green and sustainable lithium/sodium ion batteries (LIBs/SIBs) owing to their low cost, environmental benignity, renewability, flexibility, redox stability and structural diversity. However, electroactive organic compounds face many challenges in practical applications for LIBs/SIBs, such as high solubility in organic electrolytes, poor electronic conductivity, and low discharge potential as postive materials. Quinone organic materials are the most promising candidates as electrodes in LIBs/SIBs because of their high theoretical capacity, good reaction reversibility and high resource availability. While quinone electrode materials (QEMs) have so far received less attention in comparison with other organic electrode materials in secondary batteries. In this paper, an overview of the recent developments in the field of QEMs for LIBs/SIBs is provided, emphasizing on the modifications of the quinone compounds in solubility, electronic conductivity, and discharge plateaus. Finally, multifaceted modification approaches are analyzed, which can stimulate the practical applications of QEMs for LIBs/SIBs. [ABSTRACT FROM AUTHOR]

Parabens, a class of preservatives widely used in cosmetic and pharmaceutical products, are currently considered as potential emerging contaminants in the environment. Photocatalytic degradations of different parabens (methyl-, ethyl-, propyl-, and butylparaben) and their mixture were performed for the first time under visible-light irradiation using I-doped Bi 4 O 5 Br 2 photocatalysts, synthesized by a facile, fast, and energy-saving microwave route. Compared with pure Bi 4 O 5 Br 2 , I-doped samples exhibited enhanced photocatalytic activities in the degradation of the parabens. I 0.7 -Bi 4 O 5 Br 2 achieved the best performance, showing approximately 9.5, 10.4, 15.7, 24.2, and 27 times higher activities than those of Bi 4 O 5 Br 2 in the degradation of methylparaben, ethylparaben, propylparaben, butylparaben, and a mixture of parabens, respectively. The structures of the as-synthesized photocatalysts were carefully characterized, and the primary reactive oxygen species (ROS) in the photocatalytic process were identified. Photogenerated holes and superoxide radicals were found to be the key reactive species. Through doping with iodine, the valence-band potentials of the Bi 4 O 5 Br 2 photocatalysts were reduced, leading to decreases in their band-gap energies, while the separation efficiencies of the photogenerated carriers were significantly enhanced. Thus, I-doped Bi 4 O 5 Br 2 could absorb more visible-light and yield more superoxide radicals, resulting in excellent visible-light photodegradations of the parabens. In addition, the as-prepared I 0.7 -Bi 4 O 5 Br 2 catalyst maintained a strong stability of photocatalytic performance, indicating its potential for practical applications. [ABSTRACT FROM AUTHOR]

Solid electrolyte interphases (SEIs) play a crucial role in keeping sodium metal anodes (SMAs) intact and improving battery life. However, the SEIs arising from irreversible reactions between metallic Na and electrolytes fail to suppress Na dendrite growth and have sluggish Na+ kinetics. Herein, a functionalized separator modified by a sp2 carbon conjugated‐covalent organic framework (sp2c‐COF) is proposed to induce a robust SEI. X‐ray photoelectron spectroscopy (XPS) analyses and theoretical calculations demonstrate that the SEI is rich in NaF because the structure of NaPF6 is unstable due to influences from the COF separator. In situ observations show that the Na dendrite is effectively suppressed even at a high current density of 20 mA cm−2. Satisfactorily, the COF separator exhibits a high transference number of 0.78, achieving a fast Na plating/stripping process. Based on these superiorities, a symmetric cell Na|COF|Na shows stable cycling for over 1500 h at 20 mA cm−2. In addition, full cells Na|COF|NaTi2(PO4)3 (NTPO) present good rate performance (30 and 50 C) and excellent cycling stability over 5000 cycles at 5 and 10 C. The application of COFs to improve SMAs in this work demonstrates a new strategy for improving sodium metal batteries. [ABSTRACT FROM AUTHOR]

Solid electrolyte interphases (SEIs) play a crucial role in keeping sodium metal anodes (SMAs) intact and improving battery life. However, the SEIs arising from irreversible reactions between metallic Na and electrolytes fail to suppress Na dendrite growth and have sluggish Na+ kinetics. Herein, a functionalized separator modified by a sp2 carbon conjugated‐covalent organic framework (sp2c‐COF) is proposed to induce a robust SEI. X‐ray photoelectron spectroscopy (XPS) analyses and theoretical calculations demonstrate that the SEI is rich in NaF because the structure of NaPF6 is unstable due to influences from the COF separator. In situ observations show that the Na dendrite is effectively suppressed even at a high current density of 20 mA cm−2. Satisfactorily, the COF separator exhibits a high transference number of 0.78, achieving a fast Na plating/stripping process. Based on these superiorities, a symmetric cell Na|COF|Na shows stable cycling for over 1500 h at 20 mA cm−2. In addition, full cells Na|COF|NaTi2(PO4)3 (NTPO) present good rate performance (30 and 50 C) and excellent cycling stability over 5000 cycles at 5 and 10 C. The application of COFs to improve SMAs in this work demonstrates a new strategy for improving sodium metal batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] • A synergistic strategy of metal doping and in-situ carbon coating is developed to synthesize Cu-FeP@C anode. • The dispersed ultrasmall FeP is encapsulated in a 3D carbon framework and uniformly doped with Cu. • Excellent rate capability, high reversible capacity and notable long-term cycle performance is presented. • EIS, GITT and capacitive distribution calculations verified the fast ion/electron transfer kinetics. • DFT calculations are performed to understand the effect of Cu doping on electronic mobility and conductivity. FeP has emerged as an appealing anode material for lithium-ion batteries (LIBs) thanks to its high theoretical capacity, safe voltage platform and rich resources. Nevertheless, sluggish charge transfer kinetics, inevitable volume expansion and easy agglomeration of active materials limit its practical applications. Here, novel Cu-doped FeP@C was synthesized by a synergistic strategy of metal doping and in situ carbon encapsulation. The optimized Cu-doped FeP@C anode demonstrates a highly reversible specific capacity (920 mAh g−1 at 0.05 A g−1), superb rate performance (345 mAh g−1 at 5 A g−1) and long-term cycle stability (340 mAh g−1 at 2 A g−1 after 600 cycles). The electrochemical mechanism was investigated by cyclic voltammetry, kinetic analysis and DFT calculations. The results reveal that carbon frameworks can improve the conductivity and slow down the volume expansion, with highly dispersed FeP facilitating Li-ion migration during the charge and discharge processes. Additionally, Cu doping leads to rearrangement of the charge density and an additional lattice distortion in FeP, which boosts the electron mobility and enriches the surface-active sites, promoting electrochemical reaction and charge storage. This study presents a feasible and effective design for developing transition metal phosphate (TMP) anodes for high-performance LIBs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Small-molecule surface-bonded Bi-based semiconductors hybrid catalysts are developed. • Surface OVs with tunable concentrations and long-term stability is readily achieved. • Hybrid photocatalysts has superb catalytic activity for multiple contaminants removal. • Formation mechanism of surface OVs is revealed by experimental and theoretical studies. • High-valence-state Bi(3+x)+ can stabilize the surface OVs and prevent its deactivation. Constructing oxygen vacancies (OVs) with desired concentration and stability on the surfaces of semiconductors has been demonstrated to be a powerful tactic to enhance their photocatalytic performances. Nevertheless, forming OVs usually requires rigorous conditions, and OVs harshly suffer from deactivation during photoreaction. Herein, a facile strategy is developed to introduce surface OVs with tunable concentrations and long-term stability in bismuth-based semiconductors (BBS) through organic small-molecule surface-bonding. Taking I-doped BiOCl (I-BiOCl) as a model photocatalyst and catechol and its derivatives as ligands, a series of organic/I-BiOCl bonded hybrid photocatalysts are successfully synthesized. Compared with I-BiOCl, hybrid photocatalysts exhibited substantially enhanced catalytic activity toward multiple contaminants removal. Experimental characterizations and DFT calculations reveal a strong interfacial interaction between organic ligands and BBS through the formation of Bi O C bonds, which lengthen Bi-O bonds within [Bi 2 O 2 ]2+ structural units and reduce the formation energy of OVs, facilitating the escape of lattice O atoms and thus producing abundant surface OVs. More importantly, the concentration of OVs can be easily regulated by controlling the number of organic ligands, and the OVs exhibit high stability during photoreaction, attributing to the existence of high-valence-state Bi(3+x)+ that is near the OVs, which would not be re-oxidized by oxidative species like the low-valence-state Bi(3-x)+, that is, they would not be reset to original Bi3+. As a verification of its universality, the surface bonded strategy has been successfully extended to other BBS. [ABSTRACT FROM AUTHOR]

Lithium-ion batteries (LIBs) with LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM811) cathodes have a high energy density, but their long-cycle performance, especially at high temperature, should still be improved due to the instability of the NCM811 cathode-electrolyte interphase. In this work, 2, 2, 2-Trifluoroethyl p -Toluenesulfonate (TPTS) is introduced as a functional film-forming electrolyte additive design to improve the long-term stability of graphite/NCM811 batteries. The preferential redox reactions of TPTS molecules play a pivotal role in fostering the creation of a sulfur-riched interphase, characterized by low impedance. This interphase works to fortify the interfacial structure, effectively inhibiting the dissolution of transition metal ions. Therefore, in comparison to the graphite/NCM811 pouch batteries lacking additive, TPTS enhance the long-cycle capacity retention from 47 % to 80 % after 450 cycles at 45 °C. What's more, TPTS suppresses outgassing and demonstrates enhanced capacity maintenance for the battery even after storage at 60 °C. This work not only demonstrates the stabilizing impacts of TPTS on the electrode-electrolyte interphase and its enhancement of cycling performance at elevated temperatures but also introduces a novel approach for the practical utilization of functional electrolytes matching high-nickel LIBs. 2, 2, 2-trifluoroethyl p -toluenesulfonate (TPTS) is developed as a bifunctional film-forming electrolyte additive to enhance the long-cycle stability of graphite/NCM811 pouch batteries at elevated temperature. The dense interphase constructed by TPTS inhibits the dissolution of TMs and maintains the integrity of electrode materials. This work provides an effective electrolyte design strategy for the application of high nickel lithium-ion batteries. [Display omitted] • TPTS constructs low-impedance interphase with sulfur-containing components. • TPTS improve the high temperature stability of graphite/NCM811 pouch battery. • TPTS-derived interphase maintains structure integrity. • Working mechanism of TPTS is elucidated. [ABSTRACT FROM AUTHOR]

• NaDFP preferentially deposits on HC anode can induce a low-impedance interphase. • Interphase on NFM cathode inhibits iondissolution and maintains structure integrity. • NaDFP improves battery's cycle and storage performance over a wide temperature range. An electrolyte containing a sodium difluorophosphate (NaDFP) dual-functional additive is developed to enhance the temperature performance of NaNi 0.33 Fe 0.33 Mn 0.33 O 2 (NFM)/hard carbon (HC) sodium-ion batteries (SIBs). The addition of NaDFP in the electrolyte not only induces solid electrolyte interphases (SEIs) and cathode electrolyte interphases with excellent properties on the anode and cathode surfaces but also optimizes of the solvation structure of sodium ions, resulting in a better cycle stability of NFM/HC SIBs over a wide temperature range from −30 °C to 60 °C. In addition, high capacity retentions of 85 % after 700 cycles at 25 °C, 90 % after 150 cycles at −10 °C and 90 % after 150 cycles at 45 °C are achieved, respectively. And those common problems such as gas generation and sodium evolution of pouch NFM/HC SIBs are also effectively relieved, indicating the promising application prospect of NaDFP additive in the functional electrolyte of NFM/HC SIBs. [ABSTRACT FROM AUTHOR]

Ab initio molecular dynamics (AIMD) simulations were performed to study the adsorption of the 1-hydroxyethane-1,1-diphosphonic acid (HEDP) molecule on the Fe (100) surface. Through molecular dynamics trajectory, changes in bond length and angle, density distribution, interaction region indicator (IRI) and electron localization function (ELF), the fundamental adsorption mechanism of HEDP on the iron surface was disclosed in detail. The oxygen atoms of four phosphonic acid groups of HEDP coordinated with the four Fe atoms form a stable adsorption on the iron (100) surface. The HEDP molecule is slightly distorted to bind with O atoms after adsorption. The bond length change tracking results show that the adsorption occurs very quickly. IRI analysis and Bader charges show that the electrostatic interaction between HEDP and the iron surface is strong and responsible for the stable adsorption state. The interaction between deprotonated O atoms and iron surface is stronger than that between protonated O atoms and iron surface. [ABSTRACT FROM AUTHOR]

• Four representative agricultural waste plant biomasses with increased crystalline cellulose from south China region are selected to synthesize hard carbons. • The amorphous contents are separated and extracted to investigate their synergistic effect on sodium storage. • It is found that, the crystalline cellulose contributes most to the capacity due to high graphite degree and abundant closed pores, while lignin is beneficial to ion diffusion and cycle stability. • SCB-1300 exhibits excellent sodium storage performance due to high crystalline cellulose (46.9%) and lignin. • A reasonable selection of biomass precursor compositions may enhance the synergistic effects and thus guide developing low-cost and high-performance anode materials of SIBs. To further understand the structure–activity relationship of hard carbon as the anode material of sodium-ion batteries (SIBs), four representative biomass materials with increased crystalline cellulose contents of 20.4%, 30.0%, 46.9%, and 65.3%, from the common agricultural byproducts found in the South China region are selected as precursors: rice husk (RH), straw (ST), sugar cane bagasse (SCB), and bamboo wood powders (BWP). Furthermore, the amorphous contents are separated and extracted to investigate their synergistic effect on sodium storage. It is demonstrated that, crystalline cellulose can improve the graphitization degree and form enormous narrow closed pores, thus contributing a high reversible capacity. During the pyrolysis and carbonization, hemicellulose may decompose to form a longer graphite-like layer and larger but fewer closed pores. Besides, lignin decomposes to form a porous structure, which is beneficial for ion diffusion and cycle stability. The hard carbon SCB-1300 with blocky and tubular structures is synthesized by sugarcane bagasse, which has an appropriate crystalline cellulose concentration of 46.89%, exhibiting the highest reversible capacity of 206.27 mAh g−1 at 0.5 C, as well as high capacity retention of 95.73% after 700 cycles. Reasonable selection of biomass precursor compositions, such as high content of crystalline cellulose and lignin, may enhance the synergistic effects and thus guide developing low-cost and sustainable anode materials of SIBs with excellent electrochemical performance. [ABSTRACT FROM AUTHOR]

The introduction of oxygen vacancies (OVs) into photocatalysts has proven to be a successful tactic to boost CO 2 reduction. However, the challenge lies in acquiring OV sites that are stable in the long term, highly dispersed, and tunable in concentration. Herein, an innovative configuration, referred to as N-Bi(3+x)+--O V, was developed for the model semiconductor Bi 2 O 2 CO 3 via an in situ anion doping approach. The structure enables the synthetic photocatalyst to exhibit superb CO 2 photoreduction performance, with approximately 100% CO selectivity and remarkable long-term stability. Experimental studies and density functional theory (DFT) calculations show that replacing O2- with N3- uniformly in the [Bi 2 O 2 ]2+ structural unit increases the chemical valence of Bi, elongates nearby Bi─O bonds, releases lattice O, improves CO 2 absorption, and decreases the energy barrier for the formation of the critical intermediate *COOH. This study offers new insights and potential opportunities for the development of reliable defect-type semiconductors and their catalytic applications. [Display omitted] • Ultrathin N-doped Bi 2 O 2 CO 3 nanosheets were constructed via a hydrothermal route. • Atomic-level dispersed N doping results in a unique N-Bi(3+x)+--O V structure. • NBOC exhibits durable CO 2 photoreduction activity and nearly 100% CO selectivity. • Mechanism of stable OVs by N doping is revealed by experimental and DFT studies. • N-Bi(3+x)+-O V stabilizes OVs, boosts CO 2 adsorption, and reduces *COOH formation energy. [ABSTRACT FROM AUTHOR]

Abstract: Tri-phase (anatase, rutile, and brookite), bi-phase (anatase and rutile), and mono-phase (rutile) TiO2 nanomaterials with different morphologies were successively synthesized using a hydrothermal-hydrolysis method and adjusting the Ti4+/Ti3+ molar ratio in a precursor solution. The properties of the fabricated nanomaterials were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), photocatalytic reaction, and other techniques. It has been shown that TiO2 nanorods can be obtained by increasing the Ti4+/Ti3+ molar ratio in a precursor solution from 1:0 to 0.3:0.7. TiO2 nanoparticles are formed if the Ti3+ fraction in the solution is further increased. The selective synthesis of TiO2 nanomaterials is explained by a decrease in the reaction rate and by changes in acidity with increasing Ti3+ content. The tri-phase nanorods and bi-phase nanoparticles synthesized with Ti4+/Ti3+ molar ratios from 1:0 to 0.8:0.2 and 0.2:0.8 to 0:1, respectively, have a higher degradation ability with respect to methylene blue aqueous solutions under UV irradiation at ambient temperature compared to purely rutile TiO2 nanorods synthesized with Ti4+/Ti3+ molar ratios from 0.7:0.3 to 0.3:0.7. The high photocatalytic activity of the multi-phase TiO2 samples is primarily attributed to their larger band gap and suppressed recombination of photo-generated electron–hole pairs. [Copyright &y& Elsevier]

The low dielectric polymer films have drawn great attention to the application as the dielectric insulating materials in high‐frequency circuit boards, while the weak adhesion to the copper foils and the poor processability resulted from the fluorinated or rigid structures limited their high‐frequency application. In this work, the low dielectric and high adhesive polyimide/fluorinated ethylene propylene (PI/FEP) nanocomposite film for high‐frequency flexible circuit board application is developed. It is indicated that the fluorocarbon surfactants can significantly improve the dispersion of FEP in PI substrate, and thus, the PI/FEP nanocomposite film exhibits excellent mechanical properties, including the tensile strength increases to 46.6 MPa and the elongation at the break increases to 13.7%. Importantly, at the high‐frequency of 10 GHz, the 60 wt% FEP filled PI nanocomposite film displays an ultralow dielectric loss (0.006) and a reduced dielectric constant (2.69). In addition, the high‐frequency flexible circuit board with the PI/FEP film as the dielectric insulating layer has a high peel strength of 0.75 N mm−1, indicating this PI/FEP nanocomposite film can meet the requirements of the high‐frequency flexible circuit board application. [ABSTRACT FROM AUTHOR]

A functional electrolyte containing conventional carbonate esters solvents, LiPF 6 salt, and novel 2-fluorobenzenesulfonyl fluoride (2FF) additive is developed to stabilize the LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM811) cathode interface and enhance the performance of NCM811/graphite lithium-ion batteries (LIBs). It is indicated that due to the unique C-F and sulfonyl fluoride groups of 2FF, the NCM811/Li half batteries containing 2% 2FF electrolyte show the highest cycling performance, a coulombic efficiency of 98.4% and a capacity retention of 89.4% are obtained after 100 cycles at 0.5C. And compared to the pouch NCM811/graphite full batteries with blank electrolyte, the long cycle performance of the batteries with 2% 2FF is also increased after 500 cycles at 45 °C, the discharge capacity retention rate retains at 80.04% and the coulombic efficiency closes to 100%. The spectroscopic characterization and theoretical calculation demonstrate that the electrolyte with 2FF additive preferentially react and generate uniform CEI film. These results show that this 2FF-containing electrolyte can stabilize NCM811 cathode interface, revealing a promising prospect of the commercial application of high-nickel LIBs. • Developed a 2-fluorobenzenesulfonyl fluoride (2FF)-containing multi-functional electrolyte. • The formation of electrode/electrolyte interfacial films is regulated by using 2FF. • The performance of the batteries at high temperature is enhanced with 2FF additive. • SEI layer formed by 2FF reduces intergranular cracking of NCM cathodes. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel CNC#BOC hybrid was constructed via an innovative interfacial bonding tactic. • CNC#BOC shows high activity for selective CO 2 photoreduction under blue LED light. • Interfacial bonding promotes light harvesting, OV stability, and electron transfer. • Both DFT and experimental studies verify the multiple roles of interfacial bonding. • This work broadens the potential applications of renewable biomass nanocomposites. Biomass-derived nanocomposites represent a developing class of multifunctional materials with biomimetic implications. Here, cellulose nanocrystal interfacially bonded Bi 2 O 2 CO 3 hybrids (CNC#BOC) were fabricated via a hydrothermal approach for visible-light CO 2 photoreduction. The as-synthesized CNC#BOC demonstrated superb photocatalytic activity with a CO production rate of 15.22 μmol g-1 h−1, a selectivity of ∼ 97 %, and excellent cycling stability. Theoretical calculations and experimental studies indicated the existence of covalent bonds between the BOC and CNC, resulting in LMCT photosensitization, a narrowed bandgap energy, plentiful and stable OVs, high reactants affinity, fast electron transfer channels, and facile formation of *COOH intermediate. This study introduces a novel covalent bonding tactic for developing natural polymer-based catalysts for selective CO 2 photoreduction, which is expected to broaden the applications of environmentally friendly biomass composites. [ABSTRACT FROM AUTHOR]

Three-dimensional nitrogen–sulfur codoped layered porous carbon nanosheets (3D-NSCNs) with sulfur-regulated nitrogen content are constructed as a high-performance anode material for potassium-ion batteries (KIBs) through a gel and nitrogen–sulfur codoping process. Compared with the sample without sulfur doping, the 3D-NSCNs reveal enhanced electrical conductivity, specific surface area, and pyrrolic (N-5) and pyridinic (N-6) nitrogen contents, all of which are beneficial for increased electrochemical performances. After 200 cycles at a current density of 100 mA g−1, the 3D-NSCNs anode exhibits a specific capacity of 254.9 mA h g−1. After 2900 cycles at a higher charge–discharge current density of 1 A g−1, the specific capacity is still 171.1 mA g−1, and the capacity retention is 78.9%, indicating the application potential of the as-synthesized 3D-NSCNs as an anode material for KIBs. Domination by a surface-driven mechanism is proposed to explain the excellent rate and cycle performances and can also be validated by galvanostatic intermittent titration results, which show that the K+ diffusion coefficient in the 3D-NSCNs is improved after nitrogen–sulfur doping. This work demonstrates a new strategy to improve the electrochemical properties of carbon-based K-storage materials by increasing the N-5 and N-6 contents through sulfur doping while also producing micropores to increase the number of active sites. [ABSTRACT FROM AUTHOR]

A series of pore-controllable polyamine (PAI) layer-coated polyolefin (PE) separators (PAI-PE-1, PAI-PE-2, and PAI-PE-3) are prepared by using a phase-transfer and gravure-printing method and used to improve the safety of pouch lithium-ion batteries (LIBs) based on a PAI "guest-host transition" and PE "pore on-off" cooperative strategy. And the safety mechanism for the LIBs using PAI-PE-1, PAI-PE-2, and PAI-PE-3 separators with pore sizes of approximately 0.02, 0.17, and 0.85 μm is discussed. In the overcharge, nail, and hot box tests, the LIBs with PAI-PE separators all meet safety requirements, while the LIBs with PE separators exhibit either fire or smoke issues. The LIBs with PAI-PE-1 separators have the lowest temperature of 102 °C and the highest residual voltage of 3.97 V in the nail and hot box tests, respectively, and the LIBs with PAI-PE-3 separators have the lowest temperature of 129 °C in the overcharge test. The mechanism for the enhanced safety of LIBs with PAI-PE separators is ascribed to a PAI "guest-host transition" and PE "pore on-off" cooperative process. These results indicate that this pore-controllable PAI-PE separator has promising prospects in the application of LIBs with enhanced safety requirements. [ABSTRACT FROM AUTHOR]

• A doubly surface-modified BiOIO 3 photocatalyst was synthesized for the first time. • Iodine ions and oxygen vacancies were in situ generated by a heat treatment process. • The band gaps of modified BiOIO 3 can be modulated by heat treatment temperature. • The surface-modified BiOIO 3 exhibited superb visible-light photocatalytic activity. • The photogenerated h+ and O 2 − radicals were found to be the key reactive species. A novel BiOIO 3 photocatalyst surface-modified with both iodine ions and oxygen vacancies, was successfully synthesized via a microwave route followed by heat treatment and can be used for the efficient degradation of various environmental pollutants under visible-light irradiation. Pure BiOIO 3 , with a band gap of 3.2 eV, was first prepared by a rapid microwave method. Then, during a mild heat-treatment process, BiOIO 3 served as a self-sacrificial template and oxidant, while surface-adsorbed ethylene glycol derived from the microwave reaction acted as a reducing agent to in situ generate iodine ions and oxygen vacancies, resulting in a doubly modified BiOIO 3 product. By controlling the treatment temperature, the band gaps of the modified BiOIO 3 samples can be reversibly tuned by introducing defect energy levels below the conduction band and new impurity energy levels above the valence band, which is supported by the theoretical calculations and experimental analysis. The doubly surface-modified BiOIO 3 exhibits excellent visible-light photocatalytic performance for the degradation of several model pollutants, including parabens, rhodamine B, bisphenol A, and 4-hydroxybenzoic acid. Among the synthesized materials, the BiOIO 3 sample heat-treated at 125 °C shows a band gap of 2.18 eV and a photocatalytic activity approximately 229 times higher than that of pure BiOIO 3. The h+ and O 2 − radicals are verified to be the key reactive species in the photodegradation process through radical-trapping experiments and electron paramagnetic resonance spectroscopy. This work presents an effective strategy for developing superior visible-light photocatalysts through a mild in situ surface-modification technique. [ABSTRACT FROM AUTHOR]

[Display omitted] • Design of an N-SXP water-based binder based on the double helix structure of XG. • N-SXP forms biopolymer networks in SiO x to effectively buffer volume expansion. • N-SXP has excellent electrochemical performance under different conditions. • N-SXP action mechanism is illustrated by simulation and spectral analysis. Although SiO x can exhibit a higher specific energy than graphite material in lithium-ion batteries (LIBs), its mass commercial application still suffers from the performance degradation of SiO x anode caused by volume expansion. In this work, based on a biomimetic strategy and the unique double helix structure of xanthan gum (XG), sodium alginate (SA), XG and polyacrylic acid (PAA) are used to design and prepare a new water-based binder (N-SXP) to form a biomorphic polymer binder network in the SiO x anodes and effectively improve the cycling performance. It is indicated that the hydrogen and chemical bonding forces of N-SXP binder can form a solid multiple chain structure, and in particular, the supramolecular ion–dipole effect of each side chain is similar to that of a millipede's leg and can firmly adsorb the SiO x surface, and together with large hydroxyl groups form bonds between N-SXP and SiO x. After 600 cycles at 0.5C, the reversible capacity is 1105 mAh/g. Even after 300 cycles at 1C and 2C, a stable performance can still be obtained. In addition, 250 cycles at 40 °C 0.5C still provide 1101 mAh g-1 de-lithium specific capacity. The full battery capacity remains stable after 150 cycles at 200 mA g−1, and a rate capacity of 115 mAh g-1can be kept at 3C. The quantitative calculations by molecular simulations yield the role of N-SXP in forming the hydrogen bonds on SiO x surfaces, and combining with the spectroscopic characterization results further elucidate the functional mechanism of N-SXP binder in the SiO x anode. This biomimetic binder network pathway derived from N-SXP not only enhances the performance of SiO x anode but also provides an idea for the development of new bonding candidates of silicon-based materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • 2D/2D g-C 3 N 4 /Bi 4 O 5 Br 2 heterojunctions were constructed via a microwave route. • g-C 3 N 4 /Bi 4 O 5 Br 2 showed superior activity for selective oxidation of benzyl alcohol. • Remarkable performance with 100% conversion and greater than 99% selectivity was achieved. • DFT studies reveal a direct Z-scheme system formed via van der Waals interactions. • Z-scheme system promotes charge separation and molecular oxygen activation. Novel 2D/2D g-C 3 N 4 /Bi 4 O 5 Br 2 heterojunctions were constructed via a facile microwave-assisted tactic, which exhibited excellent selective photocatalytic oxidation of benzyl alcohol under blue LED light. The reaction rate of the optimized sample was approximately 9.2 and 5.3 times higher than those of g-C 3 N 4 or Bi 4 O 5 Br 2 alone, respectively, with more than 99% selectivity for benzaldehyde. DFT calculations and experimental studies showed that there was no chemical bonding between Bi 4 O 5 Br 2 and g-C 3 N 4 , but a direct Z-scheme system was created through weak van der Waals interactions. Electron spin resonance and radical quenching experiments revealed that the primary reactive species in the photoreaction system were superoxide radicals (•O 2 –) and holes (h+). Accordingly, the boosted photocatalytic activity of g-C 3 N 4 /Bi 4 O 5 Br 2 heterojunctions arose from its optimized energy band configuration and van der Waals Z-scheme system, which effectively activated molecular oxygen to generate •O 2 – and triggered the first step in the photoconversion of benzyl alcohol. This work demonstrates the crucial role of semiconductor band regulation in selective photocatalytic organic conversion and the effective activation of molecular oxygen by rational design of heterogeneous interfaces. [ABSTRACT FROM AUTHOR]

A sulfur-containing compound S-phenyl Benzenethiosulfonate (SPBS) is developed as an electrolyte additive to improve the electrochemical performance of LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM811)/graphite lithium-ion batteries (LIBs) in a wide temperature range. Compared with the batteries without SPBS, the capacity retention of the batteries containing SPBS increases from 58.15% to 91.48% after 1100 cycles at 25 °C and from 70.09% to 80.68% after 550 cycles at 45 °C. And after stored at 60 °C for 7 days, 14 days, and 28 days, the capacity retention rate and capacity recovery rate of the batteries containing SPBS are obviously improved. In addition, it is also shown that SPBS can inhibit the internal polarization and capacity attenuation of the batteries during low-temperature cycling, the capacity retention of the batteries containing SPBS increases from 46.3% to 81.9% after 100 cycles at −10 °C. The experimental and theoretical results demonstrate that SPBS facilitates the construction of high-quality electrode-electrolyte interfaces, reduces the electrolyte decomposition and inhibits the impedance increase. The excellent temperature performance of NCM811/graphite LIBs means the promising application prospect of SPBS-containing electrolyte. • A S-phenyl Benzenethiosulfonate (SPBS)-containing multi-functional electrolyte is developed. • The formation of electrode/electrolyte interfacial films is regulated by using SPBS. • The temperature performance of the NCM811/graphite batteries with SPBS additive is enhanced. • The film-forming mechanism of SPBS-containing electrolyte is elucidated. [ABSTRACT FROM AUTHOR]

• Graphene and silver nanoparticles (AgNPs@GO) composite is prepared as lithium anode. • The AgNPs@GO structure offers the Ag active sites to induce the lithium deposition. • The hollow and multi-layer AgNPs@GO exhibits space-confined feature of Li storage. • AgNPs@GO reveals low nucleation overpotential and stabilized Li storage performance. A flower-like oxidized graphene and metal silver nanoparticles composite (AgNPs@GO) was prepared by a spray-drying and annealing process. The AgNPs@GO exhibits three-dimensional (3D) multi-layer heterojunction structure and high surface area, which can reduce the overpotential of lithium deposition, decrease lithium dendrites, and stabilize lithium storage. Especially, an excellent electrochemical performance is obtained due to the space-confined feature of AgNPs@GO structure. At 0.25 mA cm−2 for 0.5 mAh cm−2, the AgNPs@GO-300 reveals a hysteresis voltage of only 32.3 mV at the 10th cycle and a stable coulombic efficiency of 97.1% after nearly 1000 h cycles, indicating promising prospects as lithium metal anode. [ABSTRACT FROM AUTHOR]

A 1-ethyl-3-methylimidazolium tetrafluoroborate (EMI–BF 4) ionic liquid is introduced into an electrolyte as a functional additive to enhance the low-temperature performance of LiNi 0.5 Co 0.2 Mn 0.3 O 2 (NCM523)/graphite batteries. Linear sweep voltammetry (LSV), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS) tests show that EMI–BF 4 can be oxidized in advance and produce low impedance solid-electrolyte interphase (SEI) films on the electrode surfaces. Compared with the batteries without the EMI–BF 4 additive, the capacity retention of the NCM523/graphite batteries with 1% EMI–BF 4 additive is enhanced from 82.3% to 93.8% after 150 cycles at a low temperature of −10 °C. In addition, at −30 °C, the discharge capacity of the batteries with 1% EMI–BF 4 additive is nearly doubled. And at the room temperature of 25 °C and after 400 cycles, the capacity retention also increases from 80.3% to 85.9%, and the coulomb efficiency remains at approximately 100%. These results demonstrate that EMI–BF 4 used as a functional electrolyte additive has promising prospects for application to improve the low-temperature performance of NCM523-based lithium-ion batteries. Image 1069882 • 1-ethyl-3-methylimidazolium tetrafluoroborate (EMI-BF 4) is evaluated as a low temperature electrolyte additive. • EMI-BF 4 can form interfacial films on both electrode surfaces of NCM523/graphite batteries. • The interfacial films formed on both electrodes improve their cycle stability. • The capacity retention rate of the batteries with EMI-BF4 is increased under low temperature. [ABSTRACT FROM AUTHOR]

Abstract Rechargeable lithium–sulfur (Li–S) batteries are a promising energy storage device because of their high energy density, but the poor electrical conductivity of the sulfur cathode and the polysulfide-shuttle effect still hinder the application of Li-S batteries. Herein, with the aid of compositional and structural design and the use of a controllable one-pot hydrothermal method, a three-dimensional (3D) porous reduced graphene oxide@La 2 O 3 @S (r-GO@La 2 O 3 @S) composite is fabricated for use as the cathode material of Li–S batteries. In this 3D porous structure, the effective adsorption ability of the La 2 O 3 microboards toward the polysulfides, based on strong chemical binding, and the conductivity of r-GO provide pathways to facilitate electron and ion transport while being able to accommodate the volume expansion/contraction of the sulfur cathode during the discharge-recharge processes. The r-GO@La 2 O 3 @S cathode delivers an initial reversible capacity of 1227.4 mAh g−1 and remains 668.3 mAh g−1 at 0.2 C after 200 cycles. At a higher current of 1 C, the capacity retention remains higher than 73% of the initial capacity after 100 cycles, indicating the excellent electrochemical properties of the cathode. The exceptional performance is attributed to the synergistic effects of the conductive r-GO and La 2 O 3 microboards with the active sulfur. [ABSTRACT FROM AUTHOR]

With the expanding applications, concerns about the charging safety of lithium-ion batteries (LIBs) have become more significant. In this paper, the constant-current (CC) overcharge electrode process of pouch LiCoO2/graphite batteries are analyzed at 0.25 C, and then, a self-protection mechanism for decreasing the overcharge risk of batteries is evaluated. As for the batteries passing the safety test, their typical overcharge behaviors show the battery voltage and temperature begin to dramatically increase to about 5.2 V and 65 °C from about 155% state of charge (SOC) and then decrease slowly after a short fluctuating period. The element analysis of two electrodes and separator reveals that besides the well-known metal lithium, cobalt precipitation pierces the separator and subsequently forms an internal micro-short circuit at about 155% SOC to consume the charge energy and subsequently avoid the overcharge explosion and ignition. As a conclusion, a self-protection mechanism based on an internal micro-short circuit model, which is closely related with the deposited electric lithium and cobalt and the separator porosity, is proposed and experimentally verified. These results offer an idea and method to decrease the CC overcharge risk of LIBs and can advance the safe application of LIBs. [ABSTRACT FROM AUTHOR]

Abstract Under the abusive conditions, it is demonstrated that the thermal stability of LiCoO 2 and the safety of LiCoO 2 /graphite batteries are improved by doping and coating Al and Ti elements into the bulk structure and surface of LiCoO 2. The trickle charge and the differential scanning calorimeter (DSC) results show that after coating Al and Ti oxides on the doped LiCoO 2 with 2000 ppm Al, the exothermic peak shifts to a higher temperature and the exotherm decreases, resulting in the increase of the thermal stability of LiCoO 2. In addition, compared to the LiCoO 2 without Al doping, it is also indicated that the thermal stability of LiCoO 2 can be enhanced by doping Al, the exothermic peak of the LiCoO 2 with Al doping amount of 10000 ppm is up to 250 °C. Under the abusive testing conditions including thermal shock and overcharge, the safety evaluation results of pouch polymer LiCoO 2 /graphite batteries are in good agreement with the trickle charge and DSC results. These results reveal that the thermal stability of LiCoO 2 can be used as an indicator to evaluate the safety characteristics of LiCoO 2 /graphite batteries, and especially the introduction of Al and Ti into LiCoO 2 can effectively improve the safety of LiCoO 2 /graphite batteries under the abusive conditions. Highlights • Al and Ti elements are introduced into the bulk structure and surface of LiCoO 2. • The thermal stability of LiCoO 2 is evaluated by trickle charge and DSC techniques. • The safety of LiCoO 2 /graphite battery is tested under thermal shock and overcharge. • LiCoO 2 modified with Al and Ti can improve the safety of LiCoO 2 /graphite battery. [ABSTRACT FROM AUTHOR]

Abstract A poly(vinylidene fluoride)/ethyl cellulose and amino-functionalized nano-SiO 2 (PVDF-EC-(A-SiO 2)) composite coated on polyethylene (PE) is developed as the functional separator of 5 V high-voltage lithium ion batteries with enhanced performance. Compared with the PE separator, the composite membrane has a uniform interconnected structure, an increased melting temperature from 138 °C (PE) to 140.8 °C, a decreased contact angle from 49.5° to 23.2°, and higher ionic conductivity from 0.34 mS cm−1 to 0.79 mS cm−1. In particular, the electrochemical window is raised to 5.3 V (vs. Li/Li+). LiNi 0.5 Mn 1.5 O 4 /Li batteries with this separator display a high discharge capacity of 131.6 mAh g−1 and a superior cycling stability with a capacity retention of 95.7% after 200 cycles at 0.5 C. Those results demonstrate that the PVDF-EC-(A-SiO 2)/PE composite separator exhibits a good-performance in cycling stability and thermal stability, implying promising potential application in high-voltage lithium ion batteries. Graphical abstract Image 1 Highlights • A new composite coated layer was prepared by PVDF-EC and A-SiO 2. • The uniform interconnected structure was formed by the good dispersion layer. • This structure could offer favorable channels for Li+ to improve conductivity. • The composite separator enhanced the mechanical and thermal stability remarkably. [ABSTRACT FROM AUTHOR]

The TiO 2 and copper-containing TiO 2 (Cu-TiO 2 ) micro/nanostructures are synthesized using a multi-element-doping route, and their visible-light-induced photocatalytic degradation of tetracycline hydrochloride (TC) is evaluated. Using metallic Ti powders with impurities as raw material, these two cauliflower-like micro/nanostructures can be hydrothermally synthesized through a dissolution and hydrolysis process in the NH 4 HF 2 solution and NH 4 HF 2 +CuSO 4 solution, respectively. Then, after a calcining treatment at 600 °C for 2 h, their phase compositions can be transformed from anatase to mixed anatase-rutile, the optical absorption edges are decreased from 452 and 439 nm to 569 and 581 nm, respectively. The apparent reaction rate constants for the photodegradation reaction of TC over the calcined TiO 2 and Cu-TiO 2 samples, which can be described by pseudo-first-order kinetics model, are increased from 0.00313 min −1 and 0.00407 min −1 to 0.00468 min −1 and 0.00978 min −1 , respectively. The enhanced photocatalytic degradation abilities of these TiO 2 and Cu-TiO 2 are attributed to their unique mixed phase composition and optical properties, and the trace doped Fe, Cu, F and N elements in their structure. [ABSTRACT FROM AUTHOR]

The overcharge safety and behaviors of lithium-ion batteries (LIBs) with LiCoO 2 cathode are investigated under a successive constant current (CC) and constant voltage (CV) charge mode. It is indicated that in the case of smaller charge currents, a higher probability for the LIBs passing the overcharging test can be obtained. The batteries can safely pass CC overcharge test at 0.25C to 10 V, and then about 80% batteries can also pass CV overcharge test. Whereas, with increasing the CC currents to 0.33C, 0.5C, and 1C, about 50%, 30%, and 10% batteries can directly pass the overcharge test at the CC step, and then about 20%, 10%, and 0% batteries approach 10 V and subsequent pass CV overcharge test, respectively. Besides the charge current, it is also demonstrated that whether the LiCoO 2 /graphite batteries are likely to achieve energy balance and pass the overcharge test basically depends on the formation of the internal short-circuit pathways derived from the cobalt and lithium deposition in the separator during the overcharge process. The cobalt deposition will be more uniform when the battery core has shape stability of assembly-structure, which can be used as an effective measure to raise LIBs through the overcharge test. In addition, relative more uniform cobalt dendrites can also be formed if a double layer separator is adopted, which reduces the local short-circuit risk caused by the melting or shrinkage of the separator and correspondingly improves the ratio of LIBs passing through the overcharge test. These risk reduction measures can be used in the battery manufacture to improve the overcharge safety of LIBs. [ABSTRACT FROM AUTHOR]

A commercially feasible sodium-ion pouch cell with a capacity of 650 mAh is fabricated using the ternary layered Na 0.76 Ni 0.3 Fe 0.4 Mn 0.3 O 2 and the hard carbon as the cathode and anode materials, respectively. 1.0 M NaPF 6 in the mixed carbonate solvents is served as the electrolyte. According to the calculation of the frontier molecular orbital energy, adiponitrile (ADN) has a stronger ability of electron donating than the carbonate solvents and thus is easier to be reduced on the surface of the cathode material to form the solid-electrolyte interphase (SEI) film, so ADN is selected as the electrolyte additive to improve the performance of sodium-ion battery for the first time. The transmission electron microscopy (TEM) images show that the addition of ADN enables the formation of more uniform and compact SEI film on the cathode material surface. The X-ray photoelectron spectroscopy (XPS) results indicate that ADN promotes the formation of NaF and result in the formation of NaCN as the effective components of the SEI film. The electrochemical test results demonstrate that ADN effectively improves the electrochemical performance at high -low-temperature and cycling stability of Na 0.76 Ni 0.3 Fe 0.4 Mn 0.3 O 2 as the cathode material of sodium-ion batteries, that is because the adding of ADN in electrolyte result in the formation of more effective SEI film. In particular, the battery using the electrolyte with 3% ADN exhibits the most obvious improvement, which owe to the formation of most compact, stable and effective SEI film after adding 3% ADN into the electrolyte. At the operating temperature of 45 °C, −10 °C, and −20 °C, the discharge capacity increases by 10.5%, 8%, and 13%, respectively. For the cycle life, the capacity retention of the battery without addition of ADN drops rapidly to 75% after 40 cycles, while the capacity retention of the battery with 3% ADN still remains 78% after 220 cycles. [ABSTRACT FROM AUTHOR]

The selective oxidation of benzyl alcohol (BA) into benzaldehyde (BAD) is an attractive model reaction for organic synthesis. Using a microwave-calcination route, a novel flower-like Bi 24 O 31 Br 10 with surface oxygen vacancies and bromine vacancies was successfully synthesized. In the construction of Bi 24 O 31 Br 10 , glucose acts as a complexing, reducing, and structure-directing agent. The as-synthesized Bi 24 O 31 Br 10 exhibits excellent activity for the photocatalytic aerobic oxidation of BA into BAD, with >99% conversion and >99% selectivity under blue LED irradiation at ambient conditions, which is 3.3-, 4.7-, and 27.8-fold higher than that of TiO 2 , Bi 4 O 5 Br 2 , and Bi 12 O 17 Cl 2 , respectively. The high selectivity is due to the suitable energy band of the as-synthesized Bi 24 O 31 Br 10 (E g  = 2.51 eV, valence band potential = +2.38 V), while the high conversion rate is largely due to the efficient separation of photogenerated carriers, surface defects, positively charge surface, and 3D micro/nano-architecture. The primary active species, including h + , e − , O 2 − , and OH, are all involved in the photoreaction. On the basis of experimental results and quantum-chemistry calculations, a direct hole oxidative mechanism with two-step dehydrogenation pathway was suggested. In addition, the as-synthesized Bi 24 O 31 Br 10 catalyst remains stable during the photocatalytic process, indicating its potential for practical applications. [ABSTRACT FROM AUTHOR]

In this paper, the LiNi0.5Mn1.5O4 cathode materials of lithium-ion batteries are synthesized by a co-precipitation spray-drying and calcining process. The use of a spray-drying process to form particles, followed by a calcination treatment at the optimized temperature of 750 °C to produce spherical LiNi0.5Mn1.5O4 particles with a cubic crystal structure, a specific surface area of 60.1 m2 g−1, a tap density of 1.15 g mL−1, and a specific capacity of 132.9 mAh g−1 at 0.1 C. The carbon nanofragment (CNF) additives, introduced into the spheres during the co-precipitation spray-drying period, greatly enhance the rate performance and cycling stability of LiNi0.5Mn1.5O4. The sample with 1.0 wt.% CNF calcined at 750 °C exhibits a maximum capacity of 131.7 mAh g−1 at 0.5 C and a capacity retention of 98.9% after 100 cycles. In addition, compared to the LiNi0.5Mn1.5O4 material without CNF, the LiNi0.5Mn1.5O4 with CNF demonstrates a high-rate capacity retention that increases from 69.1% to 95.2% after 100 cycles at 10 C, indicating an excellent rate capability. The usage of CNF and the synthetic method provide a promising choice for the synthesis of a stabilized LiNi0.5Mn1.5O4 cathode material.Micro/nanostructured LiNi0.5Mn0.5O4 cathode materials with enhanced electrochemical performances for high voltage lithium-ion batteries are synthesized by a co-precipitation spray-drying and calcining routine and using carbon nanofragments (CNFs) as additive. [ABSTRACT FROM AUTHOR]

The fabrication of robust sensors for the monitoring of emerging contaminants in real-life water samples has received much attention. In this study, copper oxide and carbon nano-fragment modified glassy carbon electrode (CuO-CNF/GCE) based electrochemical sensor was developed for the simultaneous monitoring of dihydroxybenzene isomers such as catechol (CC) and hydroquinone (HQ). The structural and morphological characterization of CuO-CNF/GCE was done by scanning electron microscopy - energy dispersive X-ray (SEM-EDX), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD). The electrochemical oxidation of HQ and CC was investigated using cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The CuO-CNF/GCE exhibited high current sensitivity for CC and HQ. The oxidation peak currents of CC at the CuO-CNF/GCE were linear function of concentration 0 μM to 150 μM, with detection limit of 2 μM (at a signal-to-noise ratio of 3) ( R 2  = 0.997) and the oxidation peak currents of HQ were linear function of concentration 3 μM to 80 μM, with 1 μM detection limit (S/N = 3) ( R 2  = 0.995). The CuO-CNF/GCE was successfully used for detecting the two dihydroxybenzene isomers in real-life water samples with high selectivity. [ABSTRACT FROM AUTHOR]

An electrochemical sensor based on a polyfurfural-electrochemically reduced graphene oxide modified glassy carbon electrode has been developed for the sensitive and rapid determination of nitrofurazone. The morphologies and properties of the sensor were characterized by electrochemical impedance spectroscopy, scanning electron microscopy, cyclic voltammetry, and differential pulse voltammetry (DPV). In pH 7.0 Britton–Robinson buffer solution, the as-prepared polyfurfural-electrochemically reduced graphene oxide modified glassy carbon electrode shows excellent electrocatalytic performance for the electrochemical reduction of nitrofurazone, and the reduction peak current is about 9.45, 1.31, and 1.25 times higher than that of the bare glassy carbon electrode, polyfurfural modified glassy carbon electrode, and electrochemically reduced graphene oxide modified glassy carbon electrode, respectively. The DPV determination of nitrofurazone indicates that the linear range and detection limit of nitrofurazone are 1–50 and 0.25 µmol/dm3, respectively. In addition, this sensor exhibits high selectivity, reproducibility, stability, and also was successfully used to directly determine nitrofurazone in the commercial antibacterial lotion with comparative sensitivity to high-performance liquid chromatography, showing its promising application prospects. [ABSTRACT FROM AUTHOR]

Today, with the massive application of lithium ion batteries (LIBs) in the portable devices and electric vehicles, to supply the active materials with high-performances and then to recycle their wastes are two core issues for the development of LIBs. In this paper, the spent graphite (SG) in LIBs is used as raw materials to fabricate two comparative high-capacity graphite anode materials. Based on a microsurgery-like physical reconstruction, the reconstructed graphite (RG) with a sp 2 +sp 3 carbon surface is prepared through a microwave exfoliation and subsequent spray drying process. In contrast, the neural-network-like amorphous sp 2 +sp 3 carbon-coated graphite (AC@G) is synthesized using a self-reconfigurable chemical reaction strategy. Compared with SG and commercial graphite (CG), both RG and AC@G have enhanced specific capacities, from 311.2 mAh g −1 and 360.7 mAh g −1 to 409.7 mAh g −1 and 420.0 mAh g −1 , at 0.1C after 100 cycles. In addition, they exhibit comparable cycling stability, rate capability, and voltage plateau with CG. Because the synthesis of RG and AC@G represents two typical physical and chemical methods for the recycling of SG, these results on the sp 2 +sp 3 carbon layer coating bulk graphite also reveal an approach for the preparation of high-performance graphite anode materials derived from SG. [ABSTRACT FROM AUTHOR]

The adsorptive removal of Ni2+ and Cd2+ at concentrations of approximately 50 mg L−1 in wastewater is investigated using an agricultural adsorbent, longan hull, and the adsorptive mechanism is characterized. The maximum adsorption capacity of approximately 4.19 mg g−1 Cd2+ was obtained under the optimized conditions of room temperature, pH 5.0, and a solid-to-liquid ratio of 1:30 in approximately 15 min. For Ni2+, the maximum adsorption capacity of approximately 3.96 mg g−1 was obtained at pH 4.7 in approximately 20 min. The adsorption kinetics for both metal ions on the longan hull can be described by a pseudo second-order rate model and are well fitted to the Langmuir adsorption isotherm. The adsorption mechanism of the longan hull to Ni2+ and Cd2+ ions is shown to be a monolayer adsorption of metal ions onto the absorbent surface. Thereinto, the longan hull adsorbent contains N–H, C–H, C=O, and C=C functional groups that can form ligands when loaded with Ni2+ and Cd2+, which reduces the fluorescence of the dried longan hull material. [ABSTRACT FROM AUTHOR]

Na x Mn 0.54 Ni 0.13 Fe 0.13 O 2 ( x = 0.46, 0.67) with P2-type hexagonal phase are synthesized via a sol-gel method as novel cathode materials for sodium-ion batteries. The followed characterization indicates the existence of coaxial hexagonal phase structure in two samples, among which Na 0.46 Mn 0.54 Ni 0.13 Fe 0.13 O 2 (NMNF-0.46) presents neat hexagonal nanosheets with a sharp edge, whereas Na 0.67 Mn 0.54 Ni 0.13 Fe 0.13 O 2 (NMNF-0.67) shows granular structure. Tested in sodium-ion batteries at the potential window of 2.0–4.2 V, the specific capacity of NMNF-0.46 is 132.5 mAh g −1 at a current density of 0.1C, and the capacity retention rate was 78% after 50 cycles. In contrast, the specific capacity of NMNF-0.67 is 99.5 mAh g −1 , but a high capacity retention rate of 86.8% is delivered. The promising electrochemical performance of Na x Mn 0.54 Ni 0.13 Fe 0.13 O 2 provides a meaningful reference for developing advanced cost-effective electrode materials for sodium-ion batteries. [ABSTRACT FROM AUTHOR]

As lithium-ion batteries (LIBs) find application in new fields, the specific capacity of single LIBs must be enhanced, and the backward-cell problem in battery modules must be solved. Here, Mn 3 O 4 and carbon nanofragment (Mn 3 O 4 /CNF) composites are synthesized and shown to have higher capacities than commercial graphite (theoretical capacity of approximately 372 mAh·g −1 ) and hierarchical voltage plateaus. Nanosized Mn 3 O 4 particles are introduced into the CNFs to simultaneously increase the specific capacity and prevent the corresponding LIB modules from over-discharging. The Mn 2+ -modified CNFs are spray-dried and calcined to form Mn 3 O 4 /CNF composites with 1.62%, 3.21%, and 6.74% Mn, which exhibit enhanced reversible specific capacities of 486.1, 609.3, and 539.0 mAh·g −1 , respectively, at 0.1C after 100 cycles. Furthermore, the additional voltage plateau at 1.2 V due to Mn 3 O 4 can help prevent the corresponding LIB modules from over-discharging and metallic lithium deposition on the anode. [ABSTRACT FROM AUTHOR]

The effect of diphenyl disulfide (DPDS) as a bifunctional additive on the performance of Li 1.2 Mn 0.54 Ni 0.13 Co 0.13 O 2 /graphite batteries cycled at elevated temperature was evaluated. The batteries with 1.0 wt.% DPDS exhibited a capacity retention of 68.4% after 100 cycles under 55 °C, which was higher than that without DPDS (44.4%). In addition, the self-discharge of the Li 1.2 Mn 0.54 Ni 0.13 Co 0.13 O 2 /graphite battery was also suppressed in a storage test at 85 °C for 8 h by adding 1.0 wt.% DPDS in the electrolyte. Linear sweep voltammetry and cyclic voltammetry combined with density functional theory calculations indicated that DPDS was oxidized and reduced prior to the solvent to participate in the formation of solid electrolyte interface (SEI) films on the cathode and anode simultaneously. The alternating current impedance and X-ray diffraction suggest that the SEI films derived from DPDS are helpful for enhancing the interface performance of the electrodes and protecting the Li 1.2 Mn 0.54 Ni 0.13 Co 0.13 O 2 and graphite structures from deterioration during high-temperature cycling, which is responsible for the improvement in the performance of the Li 1.2 Mn 0.54 Ni 0.13 Co 0.13 O 2 /graphite batteries at elevated temperature. [ABSTRACT FROM AUTHOR]