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In this study, ammonium phosphate ((NH4)3PO4) was employed to realize improvement by modifying the physical characteristics of the malachite surface, ensuring sustainable flotation throughout the flotation operations, and enhancing the flotation process to be more stable. Furthermore, various techniques, including X−ray photoelectron spectroscopy, were intensely used to investigate the configuration and physico-chemical surface characteristics through micro-flotation experiments, contact angle and zeta potential measurements, and XRD, ToF−SIMS, EPMA, and FTIR spectrum analyses. The FTIR findings showed that new characteristic peaks of −C(=S)−N.H. groups formed and adsorbed on the surfaces of malachite at 1636 cm-1. The −CH2 groups throughout the flotation process, further promoted the attachment of the CH3 ligand to the Cu2+ ion, and the XPS analysis confirmed this. Consequently, it can be concluded that (NH4)3PO4 played a substantial part in the improved recovery rate, as demonstrated and confirmed by the methods carried out in this study. Thus, it was used to modify the physical properties surface before adding Na2S to efficiently enhance malachite floatability and reduce the loss rate of malachite. Regarding the alterations in the physical characteristics which occurred to the malachite surface, and as a consequence of increasing the recovery results of flotation, the malachite sample treated initially with (NH4)3PO4 exhibited micro flotation results with a considerably greater flotation recovery than malachite treated initially with only Na2S ions.

Metal-organic frameworks (MOFs) have attracted a great deal of attention as ion conductive materials to design high-performance composite solid electrolytes (CSEs). However, sluggish Li+ transport arising from the physical contact...

1,2-Dimethoxyethane (DME) has been considered as the most promising electrolyte solvent for Li-metal batteries (LMBs). However, challenges arise from insufficient Li Coulombic efficiency (CE) and poor anodic stability associated with DME-based electrolytes. Here, we proposed a rational molecular design methodology to tailor electrolyte solvation for stable LMBs, where shortening the middle alkyl chain of the solvent could reduce the chelation ability, while increasing the terminal alkyl chain of the solvent could increase the steric hindrance, affording a diethoxymethane (DEM) solvent with ultra-weak solvation ability. When serving as a single solvent for electrolyte, a peculiar solvation structure dominated by contact ion pairs (CIPs) and aggregates (AGGs) was achieved even at a regular salt concentration of 1 m, which gives rise to anion-derived interfacial chemistry. This illustrates an unprecedentedly high Li||Cu CE of 99.1% for a single-salt single-solvent (non-fluorinated) electrolyte at ∼1 m. Moreover, this 1 m DEM-based electrolyte also remarkably suppresses the anodic dissolution of Al current collectors and significantly improves the cycling performance of high-voltage cathodes. This work opens up new frontiers in engineering electrolytes toward stable LMBs with high energy densities.

Silicon-based materials have been regarded as the most promising anodes for high-energy batteries, when combined with high- voltage/capacity nickel-rich layered cathodes. However, challenges arise ...

The practical applications of Li metal batteries (LMBs) have long been limited by the obstacles of low Coulombic efficiency (CE) and formation of dendrites on Li metal electrode. Herein, we demonstrated the synthesis of a novel three-dimensional (3D) nanostructured skeleton substrate composed of nitrogen-doped hollow carbon fiber/carbon nanosheets/ZnO (NHCF/CN/ZnO) using 2-methylimidazole (2-MIZ)-coated 3D cloth as a scaffold. The mechanism of formation of this novel hierarchical structure was investigated. The multilayered hierarchical structure and abundant lithiophilic nucleation sites of the substrate provide a stable environment for the deposition and stripping of lithium metal, thus preventing the generation of lithium dendrites. Consequently, the lithium anode based on the NHCF/CN/ZnO current collector demonstrated an excellent Coulombic efficiency of 96.47% after 400 cycles at 0.5 mA cm-2. The prepared NHCF/CN/ZnO/Li electrode also showed outstanding cycling performance of over 800 h and an ultralow voltage hysteresis of less than 30 mV in a symmetric cell at 5 mA cm-2 and 5 mAh cm-2. Even at a high loading of the cathode with 10.4 mg cm-2, the full cell of NHCF/CN/ZnO/Li anode with LiFePO4 can also work very well. Our work offers a path toward the facial preparation of 3D hierarchical structure for high-performance lithium metal batteries.

The Li dendrite issue is the major barrier that limits the implement of Li metal anode practically, especially at high current density. From the perspective of the nucleation and growth mechanism of the Li dendrite, we rationally develop a novel Prussian blue analogues (PBA)-derived separator, where tuning the metal ions bestows the PBAs with open metal site to confine anion movement and thereby afford a high Li

The traditional electrolyte for lithium-ion batteries is a combination of 1 M LiPF6 with a cyclic carbonate-based solvent (for example, ethylene carbonate). The lack of a suitable alternative solvent has hindered further exploration of new functional electrolytes. Here we design and synthesize a fluorinated cyclic phosphate solvent, 2-(2,2,2-trifluoroethoxy)-1,3,2-dioxaphospholane 2-oxide (TFEP), for use in lithium-ion batteries. Our design rationale is that this solvent molecule has a fused chemical structure of cyclic carbonates that can form a stable solid electrolyte interphase and organic phosphates that can trap hydrogen radicals and prevent combustion. An electrolyte formula composed of 0.95 M LiN(SO2F)2 in TFEP/2,2,2-trifluoroethyl methyl carbonate shows excellent non-flammability with zero self-extinguishing time and enables the highly stable operation of graphite anodes (~0.1 V versus lithium) and high-voltage LiNi0.5Mn1.5O4 cathodes (~4.7 V versus lithium), and thereby outperforms traditional electrolytes. This work opens up new frontiers in electrolyte developments towards safe lithium-ion batteries with higher energy densities. Non-flammable high-performance electrolytes are in high demand for rechargeable batteries. Here the authors design cyclic phosphate-based electrolytes to enable stable operations of graphite anodes and high-voltage cathodes for lithium-ion batteries.

ZnO is considered to be the next generation lithium-ion battery anode material due to its high theoretical capacity, low potential, abundant resources and low toxicity. However, high volume expansion during charge–discharge process makes ZnO powdered and agglomerated easily. In the work, we fabricate a porous carbon skeleton by using rice husk (RH) lignin, and the ZnO nanoparticles are supported on the skeleton uniformly. Its unique structure provides excellent stability and electrical conductivity. RH as a carbon source will improve the utilization rate of biomass materials in the refining process. The samples were characterised by XRD, Raman, TG, SEM and transmission electron microscopy, and the materials presented a promising Li storage properties and electrochemical performance with a discharge capacity of 898.1 mAh g−1 at 0.2C after 110 cycles, which is very close to the theoretical specific capacity of zinc oxide (978 mAh g−1).

Conventional separation membranes suffer from evitable fouling and flux decrease for water treatment applications. Herein, a novel protocol of electro-enhanced membrane separation is proposed for the efficient treatment of microsized emulsions (∼1 μm) by rationally designing robust electroresponsive copper metallic membranes, which could mitigate oil fouling and coenhance permeance (from ∼1026 to ∼2516 L·m

Lithium‐Ion Batteries In article number 2101646, Jianhui Wang, Atsuo Yamada and co‐workers report salt‐concentrated electrolytes can overcome various challenges for lithium‐ion full cells that operate in a wide temperature range from ‐20 to 100 °C. This achievement contributes to building a novel power battery pack that requires no thermal management system and deliveries greatly enhanced systematic energy densities in both gravimetry and volumetry. [Image: see text]

Abstract: Platycodonis Radix (Jiegeng), the dried root of Platycodon grandiflorum, is a traditional herb used as both medicine and food. Its clinical application for the treatment of cough, phlegm, sore throat, pulmonary and respiratory diseases has been thousands of years in China. Platycodin D is the main active ingredient in Platycodonis Radix, which belongs to the family of pentacyclic triterpenoid saponins because it contains an oleanolane type aglycone linked with double sugar chains. Modern pharmacology has demonstrated that Platycodin D displays various biological activities, such as analgesics, expectoration and cough suppression, promoting weight loss, anti-tumor and immune regulation, suggesting that Platycodin D has the potential to be a drug candidate and an interesting target as a natural product for clinical research. In this review, the distribution and biotransformation, pharmacological effects, metabolic mechanism and safety evaluation of Platycodin D are summarized to lay the foundation for further studies.

In order to predict the microstructures and hardness evolution of tailored hot stamping (THS) component, a thermo-mechanical-metallurgical couple finite element model was established. In particular...

Finding new means to enhance the performance of triboelectric nanogenerators (TENGs) is an ongoing pursuit. We report a novel flexible TENG made of highly porous cellulose nanofibril (CNF)/polyethylenimine (PEI) aerogel film paired with polyvinylidene fluoride (PVDF) nanofiber mats that exhibits outstanding triboelectric outputs. Modifying CNF with PEI not only enhances the mechanical properties of the CNF/PEI aerogel, but also greatly improves the power density by 14.4 times due to the enhanced tribopositivity. The triboelectric performance is further improved by employing multiple layers of PVDF mats. The TENG made of the CNF/PEI aerogel paired with four layers of PVDF mats exhibited an 18.3 times and 97.6 times improvement in output voltage and power density, respectively, compared to the TENG made of one layer of PVDF mat. The peak output power density reached 13.3 W/m2 at a load resistance of 106 Ω. Furthermore, the novel TENG displays extraordinary sensitivity when used as a self-powered sensor. It can detect not only human motion like arm bending and footsteps, but also small forces like finger tapping, water dripping, and the vibration of the substrate it is attached to. Therefore, this study not only demonstrates a high performance TENG, but also provides new insights into the design, fabrication, and application of TENGs.

A simple and effective strategy was developed to prepare a three-dimensional manganese oxynitride nanowire (MnOxNy)–reduced graphene oxide (RGO)–cellulose nanofibril (CNF) aerogel electrode with high areal mass loading (∼6.02 mg cm−2). The electrical conductivity and electrochemical performance of MnO2 nanowires were intrinsically improved by inducing oxygen vacancies and nitrogen doping during hydrazine vapor treatment. Due to the synergistic effects of highly conductive RGO, highly pseudocapacitive MnOxNy, a highly open and continuous porous aerogel structure, and the superior hydrophilicity of CNFs, the novel MnOxNy/RGO/CNF aerogel electrode we developed demonstrated a high capacitance of 455.8 F g−1 (2743.7 mF cm−2) and excellent rate capability. Pairing it with the similarly developed molybdenum oxynitride (MoOxNy)/RGO/CNF negative electrode, the asymmetric supercapacitors (ASCs) can achieve a high voltage window of 1.8 V, revealing a high energy density of 49.0 W h kg−1 at a power density of 953.7 W kg−1 in an aqueous electrolyte (i.e., 1.0 M Na2SO4 solution) and 43.7 W h kg−1 at a power density of 948.3 W kg−1 in a solid-state polymer gel electrolyte (i.e., poly(vinyl alcohol)/Na2SO4). This strategy for engineering high-performance electrodes with high mass loading will open up new opportunities for developing highly efficient energy storage devices for practical applications.

Fe2O3-based cathode materials show high theoretical specific capacitance and a wide potential range, but it is limited development due to poor electrical conductivity, undesired rate capacity and long-term cycling stability. Herein, we introduce the interconnected NiS/Co3S4 nanosheets grown on Fe2O3 substrate (Fe2O3@NiS/Co3S4) through a facile in situ solution vulcanization process. Because of the synergistic effect between the Fe2O3 nanoparticles and NiCo-S nanosheets and its unique three-dimensional open structure providing abundant channels and active sites, it is deeply investigated the electrochemical performances as positive material of supercapacitors. Meanwhile, the electrode material exhibits specific capacity of 1213.7 F g−1 at 1 A g−1, about 64.7% capacity retention at 10 A g−1 and steady cycling performance about 85.2% retention after 5000 cycles at 5 A g−1. Finally, an asymmetric supercapacitor was assembled based on Fe2O3@NiS/Co3S4 and active carbon as the positive and negative electrodes. The energy density is 43.8 Wh kg−1 at the power density of 810 W kg−1. At the same time, 92.4 % capacitance retention after 10,000 cycles at 5 A g−1 was obtained.

The operating temperatures of commercial lithium‐ion batteries (LIBs) are generally restricted to a narrow range of −20 to 55 °C because the electrolyte is composed of highly volatile and flammable organic solvents and thermally unstable salts. Herein, the use of concentrated electrolytes is proposed to widen the operating temperature to −20 to 100 °C. It is demonstrated that a 4.0 mol L−1 LiN(SO2F)2/dimethyl carbonate electrolyte enables the stable charge–discharge cycling of a graphite anode and a high‐capacity LiNi0.6Co0.2Mn0.2O2 cathode and the corresponding full cell in a wide temperature range from −20 to 100 °C owing to the highly thermal stable solvation structure of the concentrated electrolyte together with the robust and Li+‐conductive passivation interphase it offered that alleviate various challenges at high temperatures. This work demonstrates the potential for the development of safe LIBs without the need for bulky and heavy thermal management systems, thus significantly increasing the overall energy density., Owing to the highly stable solvation structure, concentrated electrolyte enables the stable operation of LiNi0.6Co0.2Mn0.2O2|graphite full cells in a wide temperature range from −20 to 100 °C, which alleviates various challenges faced by commercial dilute electrolytes. This study demonstrates the potential to build a safe battery system without the bulky and heavy thermal management system, thus significantly increasing the overall energy density.

Flexible nanogenerators (NGs) that are capable of harvesting ubiquitous mechanical energy from ambient environments have attracted significant attention during the past decade. Herein, a simple and scalable technique has been demonstrated to fabricate a new class of high-performance flexible compact triboelectric NGs using porous aerogel films. These porous aerogel film-based NGs can exhibit significant electric outputs without the use of traditional piezoelectric materials or traditional triboelectric assembly (i.e., the need of airgap). To explain the high electric outputs generated from the porous aerogel film-based generators, a mechanoradical-based mechanism was proposed and a series of systematic studies were carried out to substantiate this new mechanism. These systematic studies have demonstrated that high-performance flexible NGs can be made from porous mechanoradical-generating polymer films. The outstanding electric outputs from this new family of compact triboelectric NGs can be attributed to the reversible and transient mechanoradicals resulting from bond breaking of polymer chain, thus leading to a significant amount of transient dipole moments, as well as the permanent electric dipole moments possessed by the mechanoradical-induced polar groups. The elucidation of the potential mechanisms for this family of porous mechanoradical-generating polymers will lead to a new class of energy harvesting materials and high-performance, low-cost, and flexible energy generation devices.

A novel polydimethylsiloxane (PDMS)/cellulose nanocrystal flake (CNCF) composite triboelectric nanogenerator (CTG) using CNCFs as effective dielectrics exhibited a 10-times-enhanced triboelectric performance compared with its pure PDMS counterpart. Positive charges generated on the surface of the CNCFs during cyclic compression boosted electron transfer and induced extra charges. The CTG exhibited an instantaneous output power (density) of 1.65 mW (0.76 mW cm−2) under continuous operation.

A free-standing, lightweight, highly porous, and highly flexible cellulose nanofibril (CNF)–reduced graphene oxide (RGO)–molybdenum oxynitride (MoOxNy) aerogel film electrode was synthesized by freeze-drying a CNF/GO/MoO3 aqueous dispersion followed by subsequent in situ hydrazine reduction. Due to the partial reduction and nitrogen doping of the MoO3 nanobelts and the highly open and continuous porous structure, the free-standing CNF/RGO/MoOxNy aerogel film electrode delivered an outstanding specific capacitance of 680 F g−1 in an aqueous electrolyte and 518 F g−1 in an ionic liquid electrolyte in a three-electrode configuration at a current density of 1.0 A g−1. Furthermore, highly flexible and all-solid-state supercapacitors using CNF/RGO/MoOxNy as electrodes and either a hydrogel or ionogel as the electrolyte were fabricated and both types of supercapacitors demonstrated high specific capacitance and excellent long-term cycling stability. Remarkably, the solid-state supercapacitor devices fabricated using an ionogel electrolyte demonstrated an energy density of 114 W h kg−1 (corresponding to a volumetric energy density of 18.8 W h L−1), which is among the highest values achieved for any type of solid-state supercapacitor and is even comparable to the energy densities of Li-ion batteries. Therefore, this study provides a simple and cost-efficient method for fabricating flexible energy storage devices with excellent electrochemical performance.

Aqueous Na- or K-ion batteries could virtually eliminate the safety and cost concerns raised from Li-ion batteries, but their widespread applications have generally suffered from narrow electrochemical potential window (ca. 1.23 V) of aqueous electrolytes that leads to low energy density. Herein, by exploring optimized eutectic systems of Na and K salts with asymmetric imide anions, we discovered, for the first time, room-temperature hydrate melts for Na and K systems, which are the second and third alkali metal hydrate melts reported since the first discovery of Li hydrate melt by our group in 2016. The newly discovered Na- and K- hydrate melts could significantly extend the potential window up to 2.7 and 2.5 V (at Pt electrode), respectively, owing to the merit that almost all water molecules participate in the Na+ or K+ hydration shells. As a proof-of-concept, a prototype Na3 V2 (PO4 )2 F3 |NaTi2 (PO4 )3 aqueous Na-ion full-cell with the Na-hydrate-melt electrolyte delivers an average discharge voltage of 1.75 V, that is among the highest value ever reported for all aqueous Na-ion batteries.

Superhydrophobic and crosslinked poly(vinyl alcohol) (PVA)/cellulose nanofibril (CNF) aerogel microspheres were prepared via a combination of the water-in-oil (W/O) emulsification process with the freeze-drying process, followed by thermal chemical vapor deposition of methyltrichlorosilane. The oil phase and the cooling agent were judiciously selected to ensure that the frozen ice microspheres can be easily separated from the emulsion system. The silanized microspheres were highly porous with a bulk density ranging from 4.66 to 16.54mg/cm(3). The effects of the solution pH, stirring rate, and emulsifier concentration on the morphology and microstructure of the aerogel microspheres were studied. The highly porous structure of the ultralight aerogel microspheres demonstrated an ultrahigh crude oil absorption capacity (up to 116 times its own weight). This study provides a novel approach for the large-scale preparation of polymeric aerogel microspheres with well-controlled particle sizes that can be used for various applications including oil and chemical spill/leak clean-up.