Low Redox Research Articles

LiF-Rich Alloy-Doped SEI Enabling Ultra-Stable and High-Rate Li Metal Anode.

Li metal is regarded as the "Holy Grail" in the next generation of anode materials due to its high theoretical capacity and low redox potential. However, sluggish Li ions interfacial transport kinetics and uncontrollable Li dendrites growth limit practical application of the energy storage system in high-power device. Herein, separators are modified by the addition of a coating, which spontaneously grafts onto the Li anode interface for in situ lithiation. The resultant alloy possessing of strong electron-donating property promotes the decomposition of lithium bistrifluoromethane sulfonimide in the electrolyte to form a LiF-rich alloy-doped solid electrolyte interface (SEI) layer. High ionic alloy solid solution diffusivity and electric field dispersion modulation accelerate Li ions transport and uniform stripping/plating, resulting in a high-power dendrite-free Li metal anode interface. Surprisingly, the formulated SEI layer achieves an ultra-long cycle life of over 8000 h (20,000 cycles) for symmetric cells at a current density of 10 mA cm-2. It also ensures that the NCM(811)//PP@Au//Li full cell at ultra-high currents (40 C) completes the charging/discharging process in only 68 s to provide high capacity of 151 mAh g-1. The results confirm that this scalable strategy has great development potential in realizing high power dendrite-free Li metal anode.

LiF‐Rich Alloy‐Doped SEI Enabling Ultra‐Stable and High‐Rate Li Metal Anode

AbstractLi metal is regarded as the “Holy Grail” in the next generation of anode materials due to its high theoretical capacity and low redox potential. However, sluggish Li ions interfacial transport kinetics and uncontrollable Li dendrites growth limit practical application of the energy storage system in high‐power device. Herein, separators are modified by the addition of a coating, which spontaneously grafts onto the Li anode interface for in situ lithiation. The resultant alloy possessing of strong electron‐donating property promotes the decomposition of lithium bistrifluoromethane sulfonimide in the electrolyte to form a LiF‐rich alloy‐doped solid electrolyte interface (SEI) layer. High ionic alloy solid solution diffusivity and electric field dispersion modulation accelerate Li ions transport and uniform stripping/plating, resulting in a high‐power dendrite‐free Li metal anode interface. Surprisingly, the formulated SEI layer achieves an ultra‐long cycle life of over 8000 h (20,000 cycles) for symmetric cells at a current density of 10 mA cm−2. It also ensures that the NCM(811)//PP@Au//Li full cell at ultra‐high currents (40 C) completes the charging/discharging process in only 68 s to provide high capacity of 151 mAh g−1. The results confirm that this scalable strategy has great development potential in realizing high power dendrite‐free Li metal anode.

Electrospun MOF-derived N-doped mesoporous carbon fibers embedded with ultrafine vanadium oxide as an ultralong cycling stability for potassium ion storage

Potassium-ion batteries (KIBs) are promising options for large-scale energy storage because of their low cost and low redox potential. The use of anodes with porous structures is an attractive strategy to improve the electrochemical properties of KIBs. However, the development of KIB anodes has been hindered by their low capacity and difficulty in synthesizing porous structures. Herein, ultrafine vanadium oxide nanoparticles embedded in porous N-doped carbon nanofibers (VO@PNCNFs) using electrospinning and one-step heat treatment are reported. The uniform growth of vanadium oxide crystals is facilitated by the porous structure of the carbon nanofiber. The numerous pores play a crucial role in the transfer of electrons and ions and provide structural stability to the N-doped carbon matrix. As a result, the VO@PNCNF electrode demonstrates a high reversible capacity (∼205 mA h g−1 at 1.0 A g−1), good cycle stability over 3000 cycles, and excellent rate performance (95 mA h g−1 at 3.0 A g−1).

Novel in-situ encapsulation of tin phosphide particles in MXene conductive networks as anode materials of the durable sodium-ion battery

Sodium-ion battery (SIB) is one of potential alternatives to lithium-ion battery, because of abundant resources and lower price of sodium. High electrical conductivity and long-term durability of MXene are advantageous as the anode material of SIB, but low energy density restricts applications. Tin phosphide possesses high theoretical capacity, low redox potential, and large energy density, but volume expansion reduces its cycling stability. In this study, tin phosphide particles are in-situ encapsulated into MXene conductive networks (SnxPy/MXene) by hydrothermal and phosphorization processes as novel anode materials of SIB. MXene amounts and hydrothermal durations are investigated to evenly distribute SnxPy in MXene. After 100 cycles, SnxPy/MXene reaches high specific capacities of 438.8 and 314.1 mAh/g at 0.2 and 1.0 A/g, respectively. The capacity retentions of 6.0% and 73.6% at 0.2 A/g are respectively obtained by SnxPy and SnxPy/MXene. The better specific capacity and cycling stability of SnxPy/MXene are attributed to less volume expansion of SnxPy during charge/discharge processes and relieved self-stacking of MXene by encapsulating SnxPy particles between MXene layers. Electrochemical impedance spectroscopy and Galvanostatic intermittent titration technique are also applied to analyze the charge storage mechanism in SIB. Higher sodium ion diffusion coefficient and smaller charge-transfer resistance are obtained by SnxPy/MXene.

Kelvin Probe Force Microscopy and Electrochemical Atomic Force Microscopy Investigations of Lithium Nucleation and Growth: Influence of the Electrode Surface Potential.

Lithium metal is promising for high-capacity batteries because of its high theoretical specific capacity of 3860 mAh g-1 and low redox potential of -3.04 V versus the standard hydrogen electrode. However, it encounters challenges, such as dendrite formation, which poses risks of short circuits and safety hazards. This study examines Li deposition using electrochemical atomic force microscopy (EC-AFM) and Kelvin probe force microscopy (KPFM). KPFM provides insights into local surface potential, while EC-AFM captures the surface response evolution to electrochemical reactions. We selectively removed metallic coatings from current collectors to compare lithium deposition on coated and exposed copper surfaces. Observations from the Ag-coated Cu (Ag/Cu), Pt-coated Cu (Pt/Cu), and Au-coated Cu (Au/Cu) samples revealed variations in lithium deposition. Ag/Cu and Au/Cu exhibited two-dimensional growth, whereas Pt/Cu exhibited three-dimensional growth, highlighting the impact of electrode materials on morphology. These insights advance the development of safer lithium metal batteries.

Enhanced Interfacial Electron Transfer in Photocatalyst-Natural Enzyme Coupled Artificial Photosynthesis System: Tuning Strategies and Molecular Simulations.

Laccase is capable of catalyzing a vast array of reactions, but its low redox potential limits its potential applications. The use of photocatalytic materials offers a solution to this problem by converting absorbed visible light into electrons to facilitate enzyme catalysis. Herein, MIL-53(Fe) and NH2-MIL-53(Fe) serve as both light absorbers and enzyme immobilization carriers, and laccase is employed for solar-driven chemical conversion. Electron spin resonancespectroscopy results confirm that visible light irradiation causes rapid transfer of photogenerated electrons from MOF excitation to T1 Cu(II) of laccase, significantly increasing the degradation rate constant of tetracycline (TC) from 0.0062 to 0.0127 min-1. Conversely, there is only minimal or no electron transfer between MOF and laccase in the physical mixture state. Theoretical calculations demonstrate that the immobilization of laccase's active site and its covalent binding to themetal-organic frameworksurface augment the coupled system's activity, reducing the active site accessible from 27.8 to 18.1 Å. The constructed photo-enzyme coupled system successfully combines enzyme catalysis' selectivity with photocatalysis's high reactivity, providing a promising solution for solar energy use.

Oxadiazole derivatives as stable anolytes for >3 V non-aqueous redox flow battery

Effective utilization of energy from renewable sources such as wind and solar requires the development of long duration energy storage (LDES) systems that can accommodate intermittent energy accrual. One option under investigation is the use of a redox flow battery (RFB). A significant amount of work has explored aqueous RFB systems with a variety of inorganic and organic carriers. However, moving to a nonaqueous solvent such as acetonitrile (MeCN) for RFB provides a much larger electrochemical window, which could lead to increased energy density if properly utilized. In this work, we investigate a series of 2,5-diphenyl-1,3,4-oxadiazole (DiPhenOx) derivatives as anolytes for a redox flow battery. DiPhenOx has a low voltage redox event that, while reversible by cyclic voltammetry, was determined to be irreversible during bulk electrolysis. To improve cycling performance, we introduced various ester and cyano groups to the phenyl rings of DiPhenOx using molecular engineering. We characterized these derivatives spectroscopically and electrochemically to assess their feasibility for flow battery applications. The ester derivatives with the best cycling performance were tested in a flow cell vs. ferrocene, 2,5-di-tert-butyl-1,4-bis(2-methoxyethoxy)benzene (DBBB) and thianthrene, which resulted in ∼2 V, ∼3 V and ∼3 V redox flow batteries, respectively.

Study on the Catalytic Activity Modification of Pr and Nd Doped Ce0.7Zr0.3O2 Catalysts for Simultaneous Removal of PM and NOX

Cerium-zirconium composite oxides (Ce0.7Zr0.3O2) have a remarkable effect on catalytic removal of carbon particles (PM) and nitrogen oxides (NOX) emitted from diesel engine, in order to further improve the thermal stability, oxygen storage capacity and low temperature catalytic REDOX performance of cerium zirconium composite oxides (Ce0.7Zr0.3O2), a small amount of Pr and Nd rare earth elements are doped to improve the catalytic activity of cerium zirconium composite oxides. In this paper, the composite oxide of Pr6O11–Nd2O3–CeO2–ZrO2 is prepared by unsteady co-precipitation method, and the physicochemical properties of the composite oxide catalyst are analyzed by BET, SEM, XRD and ICP. The gas adsorption capacity and catalytic activity of composite oxide catalysts are measured by temperature programmed reaction technology (TPR). The results show that the composite oxide of Pr0.05Nd0.05Ce0.6Zr0.3O2 prepared by using rare earth elements Pr and Nd inhibits the growth process of grain, refining the grain, and improving the sintering phenomenon at high temperature. The addition of Pr and Nd causes lattice defects, increases the number of oxygen vacancies, and improves the mobility of lattice oxygen, namely promotes oxide oxygen storage property, gas adsorption and catalytic oxidation reduction ability. After modification, Pr0.05Nd0.05Ce0.6Zr0.3O2 has good resistance to high temperature aging performance, prolongs the service life, reduces the PM lowest ignition temperature and minimum catalytic activity temperature of nitrogen oxide, and promotes the NOX reduction rate. For Pr0.05Nd0.05Ce0.6Zr0.3O2, the lowest ignition temperature of PM is about 150 °C, and the lowest catalytic activity temperature of NO is about 130 °C. The maximum CO2 production rate is 68.3%, and the maximum NO reduction rate is 45%.

Hollow-structured cobalt sulfoselenide as cathode host to enhance the kinetics and improve the energy density of lithium-sulfur batteries

Lithium-sulfur batteries are a promising next-generation battery system due to their high energy density, low cost, and environmental friendliness. However, the shuttle effect and resulting low redox kinetics are significant issues that currently hinder their development. The addition of catalysts to accelerate the redox process is a common strategy. Metal sulfide catalysts, in particular, have been widely studied due to their good affinity for sulfur and sulfides. Although metal sulfide show good adsorption performance for lithium polysulfides, their low conductivity does not significantly improve the kinetic performance of the battery. Additionally, the high molecular weight of the inactive sulfide leads to the low actual energy density of the battery. Thus, this study constructed the hollow structural cobalt sulfoselenide by replacing partial elemental sulfur in cobalt sulfide (Co3S4) with the higher metallicity element selenium (Se). This was done to increase catalytic activity and reduce the amount of inactive substances, ultimately leading to an increase in actual energy density. This strategy systematically investigated the electrical conductivity, catalytic activity, and inhibition of the shuttle effect of Co3S2Se2. It was found that cobalt sulfoselenide with a 1:1 ratio of sulfur to selenium exhibited higher catalytic activity than pure cobalt sulfide. Additionally, the hollow structure of cobalt sulfoselenide showed greater performance enhancement than bulk cobalt sulfoselenide. In the assembled lithium-sulfur battery, the initial specific capacity of 1294.7 mAh/g at 0.1C was obtained, and the capacity retention was 77.5 % after 100 cycles. On this basis, the structure–activity relationship between selenium-sulfur ratio and electrochemical properties will provide ideas for the design of microscopic cathode structures.

Biochemical, kinetic, and structural characterization of a Bacillus tequilensis nitroreductase.

Nitroreductases (NRs) are NAD(P)H-dependent flavoenzymes that reduce nitro aromatic compounds to their corresponding arylamines via the nitroso and hydroxylamine intermediates. Because of their broad substrate scope and versatility, NRs have found application in multiple fields such as biocatalysis, bioremediation, cell-imaging and prodrug activation. However, only a limited number of members of the broad NR superfamily (> 24 000 sequences) have been experimentally characterized. Within this group of enzymes, only few are capable of amine synthesis, which is a fundamental chemical transformation for the pharmaceutical, agricultural, and textile industries. Herein, we provide a comprehensive description of a recently discovered NR from Bacillus tequilensis, named BtNR. This enzyme has previously been demonstrated to have the capability to fully convert nitro aromatic and heterocyclic compounds to their respective primary amines. In this study, we determined its biochemical, kinetic and structural properties, including its apparent melting temperature (Tm) of 59 °C, broad pH activity range (from pH 3 to 10) and a notably low redox potential (-236 ± 1 mV) in comparison to other well-known NRs. We also determined its steady-state and pre-steady-state kinetic parameters, which are consistent with other NRs. Additionally, we elucidated the crystal structure of BtNR, which resembles the well-characterized Escherichia coli oxygen-insensitive NAD(P)H nitroreductase (NfsB), and investigated the substrate binding in its active site through docking and molecular dynamics studies with four nitro aromatic substrates. Guided by these structural analyses, we probed the functional roles of active site residues by site-directed mutagenesis. Our findings provide valuable insights into the biochemical and structural properties of BtNR, as well as its potential applications in biotechnology.

Interface-regulated S-type core–shell PCN-224@TiO2 heterojunction for visible-light-driven generation of singlet oxygen for selective photooxidation of 2-chloroethyl ethyl sulfide

Selective oxidation of sulfur mustard gas (HD) to non-toxic sulfoxide by the visible-light-catalyzed generation of singlet oxygen (1O2) is a promising degradation strategy. Although PCN-224 can absorb visible light, it suffers from rapid electron-hole recombination and low redox capacity, which limits the performance of HD degradation. Titanium dioxide (TiO2) is an excellent photocatalyst but it lacks visible-light-activity in degrading HD. In this study, PCN-224@TiO2 heterojunction with S-type core–shell structure was synthesized by in-situ growth method to prolong the visible light absorption capacity of TiO2 and inhibit the rapid recombination of PCN-224. The interface formation and internal electric field were optimized by adjusting the Zr/Ti ratio to enhance the charge transfer, redox capacity, electron-hole separation, and visible light absorption. In this study, the formation of heterojunction composites based on Zr-O-Ti linkages is demonstrated by a series of characterization methods. It is demonstrated by experiments and theoretical calculations that PCN-224@TiO2 can generate nearly 100 % 1O2 under visible light conditions without a sacrificial agent, resulting in efficient and selective oxidation of 2-chloroethyl ethyl sulfide (CEES), a simulant of HD, to non-toxic sulfoxide form.

Uniform potassium metal deposition under fast ion transportation kinetic: Porous carbon nanotube/metal–organic frameworks composite host

Potassium Metal Batteries (KMBs) are emerging as favorable candidates for next-generation high-efficiency energy storage technologies, due to their impressive specific capacity, low redox potential, and the abundance of K. Nevertheless, challenges such as dendrite growth and considerable volume expansion have been hindering in their commercial utilization. Herein, a lightweight and self-supporting flexible three-dimensional (3D) composite host with porous metal–organic frameworks and carbon-nanotube (CNT@ZIF-8) is developed. The unique design of CNT@ZIF-8 composite host offers a multitude of potassiophilic N/Zn active nuleation sites, extensive surface area, and a porous structure. These features play a pivotal role in the management of K transport dynamics, facilitating K+ prestoring and predistribution. Benefiting from the narrowed concentration polarization and uniform nucleation, a dendrite-free K metal anode is constructed. The K@CNT@ZIF-8 anode demonstrates a remarkable durability, operating for 3200 h under 0.35 mA cm−2 and 0.35 mAh·cm−2 conditions, while also maintaining stability over 650 h at 1.0 mA cm−2 and 1.0 mAh·cm−2. Additionally, the full cell of PTCDA||K@CNT@ZIF-8 variant exhibits a boosted cycling stability (88 mAh g−1 at 5 C after 1000 cycles) and rate performance (98 mAh g−1 at 20 C). The results underscore the immense potential of CNT@ZIF-8 in facilitating practical applications for energy storage.

Dual modification of current collector for high-performance lithium metal batteries by laser etching

Despite the lithium metal anode is regarded as the next generation of anode for its high energy density and low redox potential, the huge volume expansion and high reactivity between lithium and electrolyte still limit its application. Herein, a multilayer Cu current collector is designed to accommodate the volume expansion and suppress the high reactivity. Through laser etching, the structure and the chemical component of Cu foil are deeply changed. Planar Cu is etched to construct regular microstructure with different length in interval, which regulate the current density distribution and alleviate the massive volume expansion during the charging process. And the surface of microstructure reacts with air to form lithiophilic phase CuxO layer in situ resulting in stable surface of lithium metal anodes. The simple dual-modification strategy enables the half-cell to achieves a cycle life of over 240 cycles with the CE above 98%. In contrast, the initial Cu only achieve a cycle life of less than 50 cycles. Meanwhile, full battery based on multilayer current collector delivered outstanding cycle stability. This work shows an innovative sight for the modification of current collector and safe Li metal anode.

Layered Na2Ti3O7 as an Ultrastable Intercalation-Type Anode for Non-Aqueous Calcium-Ion Batteries.

Calcium ion batteries (CIBs) are a promising energy storage device due to the low redox potential of the Ca metal and the abundant reserves of the Ca element. However, the large radius and divalent nature of Ca2+ lead to its slow ion diffusion kinetics and the lack of suitable electrode materials for Ca storage. Here, a layered structure of Na2Ti3O7 (NTO) is presented as an anode material for nonaqueous CIBs. This NTO anode demonstrates a high discharge capacity of 165 mA h g-1 at 100 mA g-1 and a remarkable capacity retention rate of 80%, even after 2000 cycles at 500 mA g-1, surpassing the performance of all reported intercalation-type anode materials for CIBs. The NTO transfers to layered CaVIINaIXTi3O7 (CNTO) with intercalation of Ca2+ and extraction of Na+ during the first discharge process. Then, the CNTO undergoes the reversible insertion/extraction of Ca2+ during subsequent cycling. Additionally, density functional theory calculations reveal that NTO possesses a rapid two-dimensional diffusion pathway for Ca2+. Moreover, the full CIBs based on NTO as the anode further underscore its potential for CIBs. This work presents promising anode materials for CIBs, offering opportunities to promote the development of high-performance CIBs.

Construction of indirect dual S-scheme heterojunction CN/AP/AW mediated by Ag nanoparticles enables efficient CO2-to-CH4 photoreduction

The highly selective product generation of photocatalytic CO2 reduction is greatly hampered by the multi-electron transfer process. In this work, Ag nanoparticle mediated indirect dual S-scheme compact heterojunction CN/AP/AW was successfully prepared through varying the ratio of Na2HPO4·12H2O and Na2WO4·2H2O. In pure water, the formation rate and selectivity of CH4 reached 18.49 μmol·g−1·h−1 and 94.3 % under simulated sunlight, with a sharp contrast to CN without CH4. The multi-channel directional transfer of electrons was realized by the construction of heterojunction, which also overcomes the inherent low REDOX capacity issues of conventional type-I and type-II heterojunction. In addition to addressing the weak interfacial contact that often occurs in terpolymer, Ag nanoparticles further accelerate electron transfer as an electron capturer, resulting in rapid unwanted electron-hole recombination. Possible reaction pathways and the cause of high selectivity were predicted by in situ FT-IR. This work provides guidance for the directional and efficient generation of CO2-to-CH4.

Manganese-enriched prussian blue nanohybrids with smaller electrode potential and lower charge transfer resistance to enhance combination therapy

Prussian blue (PB) is authenticated in clinical treatment, while it generally exhibits unfavorable chemodynamic therapy (CDT) performance. Herein, we developed manganese-doped prussian blue (PBM) nanoparticles to significantly enhance both CDT and photothermal therapy (PTT) effect. The lower redox potential of Mn3+/2+ (0.088 V) in PBM against that of Fe2+/3+ (0.192 V) in PB leads to favorable electron transfer of PBM with respect to PB. Besides, PBM has a lower charge-transfer resistance (Rct) of 2.98 Ω than 4.83 Ω of PB. Once PBM entering the tumor microenvironment (TME), Mn3+ may be readily reduced by glutathione (GSH) and therein to enhance intracellular oxidative stress. Meanwhile, the superoxide dismutase (SOD)-like activity of PBM facilitates the conversion of endogenous superoxide (O2•−) into H2O2. Mn2+ subsequently catalyzes H2O2 to generate toxic hydroxyl radicals (•OH). Notably, the PBM plus laser irradiation can effectively trigger a robust immunogenic cell death (ICD) due to the combination therapy of CDT and PTT. Additionally, the mice treated by PBM followed by laser irradiation efficiently avoided splenomegaly and lung metastasis, along with significant up-regulation of the Stimulator of Interferon Genes (STING) expression. Overall, PBM significantly inhibits tumor growth and metastasis, making it a promising multifunctional nanoplatform for cancer treatment.

In situ synthesis BiOBr/Bi-TDC composite with rich oxygen vacancy to remove rhodamine B and tetracycline under ultrasound and illumination

A series of 3D hierarchical microsphere heterojunction composites combining BiOBr and Bi-MOF (Bi-TDC) supported by 2,5-thiophene dicarboxylate acid (H2TDC) was fabricated by one-step solvothermal method. Hexadecyl trimethyl bromide (CTAB) is used as the structure guide reagent and Br source to design BiOBr/Bi-TDC composites and enhance catalytic activity. The ultrasound-assisted photocatalysis effect of BiOBr/Bi-TDC for RhB and TC can reach 99.8 % and 96.1 % in 30 min, respectively. Further, the influence factor of photocatalytic degradation TC solution were explored, including pH, initial pollutant concentration, catalyst dosage and different proportions of BiOBr and Bi-TDC. The excellent catalytic activity can be attributed to the construction of heterogeneous interfaces and rich oxygen vacancies (OVs), which improve the low redox potentials and facilitate the separation of photogenerated electron-hole pairs. Radical trapping experiment is made and shown •O2− and h+ are the most active species for the photodegradation process. The EPR characteristic is also used to explore free radicals when exposed to the visible light illumination.

Controlled NiOx Defect Engineering to Harnessing Redox Reactions in Perovskite Photovoltaic Cells via Atomic Layer Deposition.

Albeit the undesirable attributes of NiOx, such as low conductivity, unmanageable defects, and redox reactions occurring at the perovskite/NiOx interface, which impede the progress in inverted perovskite solar cells (i-PSCs), it is the most favorable choice of technology for industrialization of PSCs. In this study, we propose a novel Ni vacancy defect modulate approach to leverage the conformal growth and surface self-limiting reaction characteristics of the atomic layer deposition (ALD)-fabricated NiOx by varying the O2 plasma injection time (tOE) to induce self-doping. Consequently, NiOx thin films with enhanced conductivity, an appropriate Ni3+/Ni2+ ratio, stable surface states, and ultrathinness are realized as hole-transporting layers (HTLs) in p-i-n PSCs. As a result of these improvements, ALD-NiOx-based devices exhibit the highest power conversion efficiency (PCE) of 19.86% and a fill factor (FF) of 81.86%. Notably, the optimal interfacial defects effectively suppressed the severe reaction between the perovskite and NiOx. This suppression is evidenced by the lowest decay rate observed in a harsh environment, lasting for 500 consecutive hours. The proposed approach introduces the possibility of a hierarchical distribution of defects and offers feasibility for the fabrication of large-area, uniform, and high-quality films.

Constructing 3D porous network channel on PP-based separator to achieve homogeneous deposition of lithium ions for lithium metal battery

Lithium metal anode is broadly regarded as one of the most promising anode materials for batteries due to its extremely high specific capacity, very low redox potential, and mass density. Nevertheless, non-uniform deposition of lithium ions hinder the practical application of lithium metal batteries (LMBs). Herein, it was essential to design a separator with high electrolyte affinity to inhibit the non-uniform deposition of lithium ions. In this work, the wettability and electrolyte uptake of the polypropylene (PP) separator were remarkably improved by introducing reduced graphene oxide (rGO) and polyvinylidene fluoride (PVDF) to the surface of the separator through one-sided coating. The composite separator resulted in lithium ion with high conductivity (1.35 × 10–3 S cm-1) and transfer number (0.63). After assembling the rGO/PVDF@PP separator into the LiFePO4||Li battery and conducting the test, it was found that the specific discharge capacity could still reach 136 mAh g-1 after 100 cycles at 1C. Furthermore, After 1000 h of cycling in the assembled Li‖Li symmetric battery, there is no obvious generation of lithium dendrites on the surface of the lithium metal, indicating the successful suppression of lithium dendrites by the composite separator. This study offers a promising pathway for producing large quantities of new composite separators with high levels of safety.

Waste peanut shell derived porous carbon for dendrites-free aqueous zinc-ion batteries

Zinc metal has gained much attention due to its low redox potential, high theoretical capacity and high safety. However, its stability and service life are greatly affected by side reactions such as dendrites and corrosion. Here we propose a coating material derived from peanut erythrocyte biomass waste, which enables more uniform deposition of zinc ions on the surface of zinc foil, further reduces the charge transfer resistance and improves corrosion resistance, and extends the symmetric battery life to more than 650 h of cycling stability at a current density of 0.5 mA cm−2. In addition, the Zn-MnO2 full cell protected by the assembled coating material still possessed a capacity retention rate of 56.7 % much higher than that of the bare Zn cell (43.4 %) after 1000 cycles at a current density of 1 A/g. This work provides a broader application strategy for zinc anode protection of zinc-ion batteries by utilizing low-cost peanut red skin waste.