Initial capacity loss in lithium-ion batteries (LIBs) represents a persistent challenge that diminishes achievable energy density. Existing approaches to address the initial loss primarily rely on introducing a lithium source to the anode or adding a high-capacity lithium containing additive into the cathode. However, these approaches suffer from significant drawbacks, including limited capacity enhancement, the use of expensive additives, and complex manufacturing requirements. In this work, we present a compensation strategy that harnesses electrolyte decomposition through a controlled overcharge process. This process induces electrochemical decomposition of the electrolyte at the cathode, providing additional charge capacity to compensate for the initial loss. The proposed method increases the capacity of graphite/LiFePO4 cell by similar to 7% and similar to 3% at 15 mA g(-1) and 50 mA g(-1), respectively. When paired with a hard carbon anode with a very low initial Coulombic efficiency (CE) of 70.1%, the full-cell capacity rises more significantly, by similar to 24% and similar to 14% at the same respective current densities. Our approach offers a practical and industrially compatible solution for capacity compensation, as it requires no additional additives or modifications to existing manufacturing processes. It improves capacity with almost no increase in cost. Moreover, it allows the use of low-cost, high-capacity anodes with very low initial CE in LIBs.

Biomass-derived hard carbons represent promising low-cost anode materials for sodium-ion batteries. However, their complex preparation processes and high carbonization temperatures (>1300 degrees C) incur significant energy consumption and cost, hindering sustainable production. This work presents an environmentally benign strategy utilizing low-cost waste cotton fibers to produce high-performance hard carbon anodes with a low carbonization temperature of 900 degrees C. The innovation involves the integration of a dry ball-milling pretreatment, which facilitates the phase transformation from cellulose I to cellulose II. Comprehensive microscopic and spectroscopic analyses confirm that this phase transformation promotes the formation of a microcrystalline carbon layer with enlarged interlayer spacing during subsequent low-temperature carbonization. Moreover, the electrochemical test demonstrates the ball milling-pretreatment driven hard carbon anode delivers higher reversible capacity of 270.00 mAh g(-1) compared to 166.76 mAh g(-1) for the non-ball milling samples and a high initial Coulombic efficiency of 85.34 %. It also exhibits excellent rate capability and long-term cycling stability, retaining a specific capacity of 193.85 mAh g(-1) under a high current density of 2 A g(-1) after 1300 charge-discharge cycles. Kinetic analysis further reveals that the enhanced sodium storage stems predominantly from an insertion mechanism within the engineered microcrystalline carbon layer induced by ball milling. This work establishes a cost-effective and energy-efficient pathway for transforming textile waste into high-value anode materials, advancing the sustainable development of sodium-ion battery.

Abstract LiNi0.5Mn1.5O4 (LNMO) is a promising high-energy cathode material for lithium-ion batteries due to its high operating voltage (~5 V vs. Li+/Li) which leads to a high energy density. However, the high voltage also induces unstable LNMO/electrolyte interface when cycled in regular electrolytes. In this work, we present a high-voltage ethylene carbonate (EC)/1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropylether (TTE) electrolyte that is highly compatible with LiNi0.5Mn1.5O4 batteries. Through the use of the electrolyte, we uncover two insights that go against conventional understanding. Contrary to the common belief that EC decomposes readily under high voltage, we demonstrate the outstanding high-voltage stability of both EC and the EC/TTE electrolyte. Moreover, we find that LNMO cycles in this electrolyte without forming a typical cathode/electrolyte interphase (CEI), experiencing instead a unique surface restructuring. Under the conditions of the high-voltage stability of the electrolyte and of surface restructuring, the dissolution of nickel and manganese from LNMO is also mitigated. These features lead to long-term cyclability of LNMO batteries with an average CE of 99.86%. By challenging the perceived instability of EC and revealing a CEI-free surface restructuring process, this work offers both a practical electrolyte design and a fresh interfacial stabilization concept for high-voltage batteries.

The implementation of rechargeable high-energy lithium metal batteries is hindered by the instability of lithium electrodes. The electrolyte additive, LiNO3, can significantly improve the stability of lithium electrodes. However, LiNO3 has very low solubility in carbonate electrolytes which are widely used in commercial lithium-ion batteries. Herein, we introduce N-methyl-2-pyrrolidone (NMP) as a carrier solvent into diethyl carbonate (DEC)-based electrolyte to solvate and dissolve LiNO3. It is found that, in LiFSI/DEC electrolytes, interactions between LiNO3, NMP, and fluoroethylene carbonate (FEC) reorganize the solvation structure: DEC, FEC, NMP, and NO3- are involved in coordination interactions, while FSI- ions mainly remain free. This unique configuration induces synergistic effects, achieving a Coulombic efficiency (CE) of 98.4%. Surface analysis reveals a composite solid electrolyte interphase (SEI) layer comprising Li2CO3, RCO2Li, LixN, LiF, and a rarely reported F-containing strong ionic compound. Such an SEI layer is found to be more protective and more favorable for improving the CE and kinetics.

This study introduces a highly sensitive platform for ultratrace mercury [Hg (II)] detection, utilizing a screenprinted carbon electrode (SPCE) modified with silver nanoparticles (AgNPs), chitosan (CS), and carbon nanotubes (CNTs). The AgNPs were synthesized using a green method incorporating CS and CNT hybrids, leading to their immobilization on the CNT sidewalls, resulting in nanoscale silver electrode arrays on the SPCE. Detection of Hg (II) involved the formation of Hg/Ag amalgam on the AgNPs/CS/CNT-modified SPCE surface by depositing mercury species onto elemental mercury. Hg (II) detection successfully occurred through the stripping of both Hg0 and Ag0 at a potential of +0.16 V in a supporting electrolyte (0.10 M HCl and 0.10 M KCl). This newly established detection method demonstrates exceptional selectivity and sensitivity, featuring a remarkable linear range for Hg (II) concentration from 1.0 nM to 12.6 nM, with an impressive correlation coefficient (R2) of 0.982 (n =13) and a low detection limit of 0.4 nM. The designed electrode effectively measured Hg (II) levels in textile samples, yielding acceptable recovery results, while also exhibiting remarkable reproducibility and precision. This work presents a novel, highly sensitive, and selective approach for ultratrace Hg (II) detection, with promising applications in environmental monitoring and analytical chemistry.

The uncontrollable growth of Li dendrites and large volume change during cycling limit the practical applications of Li metal anodes. Herein, the in situ-formed Pd nanoparticles locked in three-dimensional N-doped microporous carbon (Pd/NMC), which are derived from the catalyst for Buchwald-Hartwig (B-H) coupling polymerization, have been constructed to address these issues. The homogeneously distributed Pd nanoparticles effectively reduce the overpotential of Li nucleation through the reversible Li-Pd alloying reaction and boost Li+ diffusion by reducing the migration barrier. Furthermore, the Pd nanoparticles guide the Li selective nucleation and uniform growth in the 3D N-doped microporous carbon. Meanwhile, the spatial confinement effect alleviates the volume changes. As a result, the stable and reversible Li metal anode exhibits a high Coulombic efficiency of 98.7% over 1000 cycles at 1 mA cm-2. Full cells with LiFePO4 (LFP) as the cathode deliver a long lifespan of 600 cycles with 0.02% capacity decay per cycle at 2 C. This work provides a new polymerization-carbonization strategy to prepare a lithiophilic host for energy-dense Li metal batteries.

Iron oxides, such as FeOOH, Fe2O3, and Fe3O4, are promising materials for sodium-ion (NIBs) and lithium-ion (LIBs) batteries. However, the preparation of stable iron oxides for NIBs and LIBs usually involves intricate routes. In this work, we develop simple approaches for the synthesis of stable mesoporous layered iron oxide (FeOOH, Fe2O3, or Fe3O4)/reduced graphene oxide (rGO) composites for NIBs and LIBs. The approaches first involve the synthesis of rod-like-FeOOH/graphene oxide (GO) sheets via hydrolysis and electrostatic attraction. Rod-like FeOOH flattens the GO, which facilitates layered-assembly. Two reduction-induced self-assembly methods, i.e., hydrazine-assisted reduction and heat treatment can then be employed to prepare layered FeOOH/rGO and layered Fe2O3/rGO, respectively, from the flat FeOOH/GO sheets. Further thermal treatment of the layered FeOOH/rGO enables the formation of Fe3O4/rGO. All these materials possess mesoporosity. The mesopores of the materials provide preserved void spaces for volume expansion during sodiation and lithiation. The layered rGO framework serves as a conductive medium for the transport of electrons. As a result, the layered materials exhibit stable cyclability for both sodium and lithium storage. Notably, the layered FeOOH/rGO composite exhibits an impressive ability to withstand ∼1000 cycles without experiencing significant capacity decay for sodium storage.

Hard carbon materials are attracted as excellent anode materials for sodium-ion batteries due to their good electrical conductivity, high reversible capacity, low operating voltage and stable cycling performance. Herein, waste denim fabrics were used as raw material to prepare denim-based hard carbon (DHC) via a one-step carbonization method, and its sodium storage performance as an anode material for sodium-ion batteries was investigated. The effects of carbonization temperature on the microstructure and electrochemical sodium storage performance of DHC were investigated using X-ray diffraction, N2 adsorption–desorption isotherms, Raman spectroscopy, scanning electron microscopy, cyclic voltammetry and galvanostatic charge–discharge methods. The results demonstrate that DHC derived at a carbonization temperature of 1300 °C with an optimal graphitic microcrystal size, pore structure and surface defect, exhibits the best electrochemical performance. At a current density of 50 mAh·g−1, it has a reversible specific capacity of 317.1 mAh·g−1 and an initial Coulombic efficiency of 87.76

Hard carbons from cellulose are highly regarded as promising anode options for sodium-ion batteries (SIBs). However, a high carbonization temperature (>1300 degrees C) is usually required to obtain high-performance hard carbons, which leads to high-energy consumption and high cost. Moreover, hard carbons generally have poor rate capability and unsatisfactory cyclability which restrict their commercial applications. Herein, a lowtemperature (900 degrees C) approach for the preparation of high-quality hard carbons for SIBs from waste cotton fibers is reported. It involves a mercerization pretreatment to convert cellulose-I cotton fibers into cellulose-II structure and dissolve the amorphous cellulose to form highly crystalline cellulose. This pretreatment process benefits forming abundant pseudo-graphitic structures at a low carbonization temperature of 900 degrees C. Consequently, the mercerized cotton fibers-based carbons (MCFC) exhibit excellent sodium storage properties, possessing a high capacity (316 mAh g(-1) at 0.1 A g(-1)), high-rate capability (210 mAh g(-1) at 10 A g(-1)), and longterm cyclability (83.2 % retention after 3000 cycles). This mercerization approach coupled with waste cotton fibers provides a sustainable pathway for the preparation of high-quality hard carbons for SIBs.

Oxygen transport resistance (OTR) of the cathode catalyst layer (CCL) has a significant impact on the performance of polymer electrolyte fuel cells (PEFCs) because it directly affects the kinetics. In this work, poly diallyldimethylammonium (PDDA) is used to reduce the OTR in the ionomer film by decreasing the density of the ionomer film close to the surface of Pt, and increasing the naked surface of Pt. With PDDA, the polarization of CCL can be significantly reduced, for example, the oxygen reduction reaction (ORR) voltage with PDDA at 2.0 A cm–2 is 79 mV higher than the one without. The total OTR of CCL (Rtotal) with PDDA decreases by about 2.9% at 70 ° C and 250 kPa, which is mainly caused by the reduction of pressure-independent resistance (Rother). The decrease in Rother may come from the decreased O2 permeation resistance (Rionomer) through the ionomer film of Pt surface. The results show that the addition of PPDA can weaken the electrostatic interaction between sulfonate groups in ionomer and Pt, and reduce the density of ionomer on the surface of Pt. Thus, PDDA can effectively reduce the Rionomer.

Indigo, used as the main dye for the production of denim textiles, is chemically reduced by sodium dithionite in most industrial processes. The excess dithionite, sulphite, sulphate, thiosulphate, and toxic sulfide heavily contaminate the environment. Electrocatalytic hydrogenation would be a sustainable pathway for the reduction of indigo because it minimizes the consumption of chemicals and energy. In the present work, the carbon-felt (CF) supported NiMoS was prepared by electrodeposition of NiMo on the surface of CF, followed by sulfidation in an oven at 600oC. The characterizations show that NiMoS has a larger electrochemically active area and a smaller charge transfer resistance compared to Ni and NiMo. Moreover, NiMoS exhibits the thermodynamic (η10=96 mV) and kinetic (Tafel slope of 106.6 mV dec-1) properties for the electrolysis of water in strong alkaline solutions (1M KOH). In addition, NiMoS/CF was used for the electrocatalytic hydrogenation of indigo. The conversion and Faraday efficiency were improved to 99.2% and 38.1% respectively, at the optimal reaction conditions, e.g. indigo concentration (5 g/L), current density (10 mA/cm2), reaction temperature (70°C) and media of 1 M potassium hydroxide with 10%methanol (V/V). The K/S of dyeing cloth fabrics were similar using the leuco-indigo from the conventional chemical reduction and the electrocatalytic hydrogenation of indigo. The present experimental method and results provide new ideas for designing and applying novel catalytic materials for electrocatalytic hydrogenation of vat dyes.

An NiMo alloy bonded with sulfur (NiMoS) exhibits enhanced surface affinity toward water and organic molecules, thereby enhancing electrocatalytic hydrogenation (ECH) reactions through synergistic effects. In industrial processes, indigo, an ancient dye employed in the denim industry, is typically chemically reduced using sodium dithionite. However, this process generates an excess of toxic sulfide, which heavily contaminates the environment. ECH is a sustainable alternative for indigo reduction due to its reduced reliance on chemicals and energy consumption. In this study, carbon-felt (CF)-supported NiMoS was synthesized in a two-step process. First, the NiMo alloy was electrodeposited onto the CF surface, followed by sulfidation in an oven at 600 °C. NiMoS exhibits a larger electrochemically active surface area and a smaller charge transfer resistance compared to pure Ni and NiMo. Furthermore, NiMoS demonstrates excellent thermodynamic and kinetic properties for water splitting in strong alkaline solutions (1.0 M KOH). Additionally, optimal reaction conditions for the ECH of indigo were explored. Under the conditions of a 1.0 M KOH hydroxide medium with 10% methanol (v/v), an indigo concentration of 5 g L-1, a reaction temperature of 70 °C, and a current density of 10 mA cm-2, NiMoS/CF achieved remarkable improvements in both conversion (99.2%) and Faraday efficiency (38.1%). The results of this experimental work offer valuable insights into the design and application of novel catalytic materials for the ECH of vat dyes, opening up new possibilities for sustainable and environmentally friendly processes in the dye industry.

Converting waste biomass resources into electrochemical energy storage materials has been regarded as a valuable contribution to implementing sustainable energy. Herein, waste cotton fiber-based graphitized carbon/Fe7S8 (CFGC/Fe7S8) composites were successfully synthesized from sulfurization of Fe-Fe3C inter-mediates, produced by simple pyrolysis of waste cotton fabric and low-cost iron compound. The as -pre-pared CFGC/Fe7S8 composites were composed of partly graphitized carbon fiber embedded with well -dispersed Fe7S8 nanoparticles. This structure offers excellent performance for electrochemical sodium storage. Acting as an anode in sodium-ion battery, CFGC/Fe7S8 composites deliver a high discharge specific capacity of 661 mAh g-1 after 100 cycles at 0.1 A g-1 and an initial Coulombic efficiency of 85.8% and achieve a discharge specific capacity of 328 mAh g-1 after 800 cycles even at a high current density of 2 A g-1. These results demonstrate that Fe-Fe3C intermediate derived-Fe7S8 nanoparticles combined with cotton fiber -based graphitic carbon plays a significant role in the electrochemical performance of sodium ion storage. These findings present a novel strategy for transferring waste textile into high-performance sodium storage materials.(c) 2022 Published by Elsevier B.V.

Electrochemical hydrogenation is an environmentally favorable alternative to chemical reduction of indigo because it performs under ambient conditions using water as the donor of hydrogen. The purpose of this work is to fabricate electrocatalysts with high activity and durability for electrocatalytic hydrogenation of indigo. This work compares the performances of a series of Ni based catalysts (Ni, NiMo, NiP and NiMoP) on the substrate of carbon felt (CF) for electrolyzing water. Both the overpotential and Tafel slop are decreased as a function of the components as Ni > NiMo > NiP > NiMoP. Hence, NiMoP/CF shows the excellent performance based on the thermodynamics (r10 = 239 mV) and kinetics (Tafel slope = 89.7 mV$dec(-1)) for splitting water. Further, the electrode of NiMoP/CF was used for the electrocatalytic hydroge-nation of indigo. The conversion efficiency and Faradic efficiency can be improved as 26.2% and 10.7% respectively. Furthermore, the dyeing behavior of the electrohydrogenated indigo is similar to that of conventional reduction methods. Thus, the present work offers foundational results and paves the way for the design of new catalytic materials for the reduction of vat dyes. (C) 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Chitosan-based carbon materials have attracted great attention in electrochemical energy storage. Introducing iron metal or iron compounds into carbon materials favors to boost their electrochemical performance. Herein, chitosan-based graphitic carbon@Fe3C composites (CSGC@Fe3C) have been prepared as anode materials for lithium ion battery by a simple pyrolysis method. By manipulating the temperature higher than 700 °C, pure Fe3C encapsulated in chitosan-based graphitic carbon with different mass ratio from 30 to 53.8 wt% can be achieved. The resulting CSGC@Fe3C composites retain porous carbon sheet structure embedded with a large amount of Fe3C nanoparticles in size from 20 to 300 nm. The electrochemical measurements demonstrate CSGC@Fe3C with 53.8 wt% Fe3C as anode material for lithium ion battery can provide a highest reversible capacity of 423 mAh g−1 at 0.1 A g−1 over 100 charge/discharge cycles and stable cycling capacity of 195 mAh g−1 at a high current density of 2 A g−1 during 200 cycles. The catalysis of Fe3C on the reversible formation and decomposition of solid electrolyte interphase (SEI) has been corroborated and results in the improvement of surface capacitive contribution. This work provides a basic insight into metal carbides constructing biomass-based carbon anode materials to realize high-performance electrochemical energy storage device.

Solar steam production is regarded as a potential approach for extracting freshwater from undrinkable water. However, it remains a challenge to acquire a low-cost, salt-resistant, durable and efficient solar evaporator through a simple fabrication process. This work presents a plant transpiration-inspired three-dimensional (3D) solar evaporator fabricated by decorating industrial polyester fiber bundles (PFBs) with inexpensive polypyrrole (PPy). This solar evaporator is named the PPy-PFBs. Intriguingly, PFBs composed of hydrophobic polyester fibers with multiple vertical channels are capable of pumping enough water to the top of the solar evaporator through the capillary effect and storing seven times its mass of water, allowing for salt-resistant. In addition, polyester fiber is resistant to acid, alkali, mildew, and sunlight, making the PPy-PFBs durable. Along with the heat generated from sunlight absorbed by the PPy, the 3D solar evaporator can also gain energy from the environ-ment. Adjusting the exposure height and arrangement of PPy-PFBs can control the evaporation rate. The matrix arranged PPy-PFBs with an exposure height of 6 cm attains a high water evaporation rate of 3.77 kg m-2 h-1 with an energy conversion efficiency of 155.77%. Outdoor experiments demonstrate that the PPy-PFBs can extract freshwater from non-drinkable water. 1 m2 of PPy-PFBs can produce about 26 kg of fresh water per day, which is enough to meet the daily drinking water needs of 10 adults. This low-cost, easily made, salt-resistant, durable and high evaporation rate solar evaporator is appealing to alleviate the global freshwater crisis.

采用催化石墨化法将废旧棉纤维直接制备成棉纤维基石墨化碳/Fe3 C复合材料,并将该材料组装成锂离子电池,进行电化学性能表征.结果表明:在煅烧温度为700℃ 、保温时间2 h、硝酸铁浓度为1 mol/L的条件下,可以制备出棉纤维基石墨化碳/Fe3 C复合材料.通过SEM、XRD、Raman对样品进行表征,该材料由微米级的棉短纤维基石墨化碳负载纳米Fe3 C构成.在电流密度为0.1 A·g-1条件下,循环100次后,比容量保持在279 mAh·g-1,循环寿命稳定.在2 A·g-1条件下进行充放电测试,容量可达134 mAh·g-1.与直接碳化的棉纤维基碳材料相比,棉纤维基石墨化碳/Fe3 C复合材料表现出更优越的电池比容量和倍率性能.该工作将废旧棉织物通过铁离子直接催化石墨化作用,成功地构造棉纤维基石墨化碳/Fe3 C复合材料.制备过程无水洗和酸洗后处理步骤,大大简化工艺流程,为纺织废弃资源转化为锂离子电池材料提供新思路.

Transforming waste resources into energy storage materials is a new way to convert them into value-added products and help solve the problems of energy shortage and environmental pollution. A nitrogen-phosphorus co-doped activated carbon was synthesized from waste cotton fabric by combining carbonization and activation in ammonium polyphosphate and a molten salt system (ZnCl2 and KCl with a molar ratio of 52:48). The morphology, microstructure and composition of the activated carbon were characterized by SEM, nitrogen adsorption, Raman spectroscopy and XPS. Cyclic voltammetry and galvanostatic charge/discharge were used to test the supercapacitor performance of the activated carbon. Results show that the co-doped activated carbon had a specific surface area of 751 m2 g−1, a specific capacitance of 423 F g−1 at a current density of 0.25 A g−1, and a capacitance retention rate of 88.9% after 5000 cycles at a current density of 5 A g−1. The energy density was 28.67 Wh kg−1 at a power density of 200 W kg−1 for a symmetrical supercapacitor using the activated carbon.

Palladium nanomaterials (PdNPs) have drawn significant attention due to their fascinating catalytic, optical, and electrical properties. PdNPs-catalytic hydrogenation is considered as an efficient way for the remediation of inorganic and organic pollutants. Thus, a simple Konjac glucomannan (KGM) reduced and stabilized PdNPs-catalysts were green synthesized without using any toxic reagents. The maximization of PdNPs production was investigated using a factorial design of experiments, where one variable (precursor ratio, solution pH, reaction time, and temperature) was studied at a time. The surface plasmon resonance (SPR), morphology, crystallinity, particle size distribution, composition spectra, and stability of as-synthesized PdNPs were explored in detail. Results revealed that the particles are mostly in spherical shapes, smaller in size (6.48 +/- 2.19 nm) with a narrow distribution, highly crystalline (d-spacing = 0.224 nm), well stabilized (zeta potential = -17.89 mV), and coated by thin KGM layer of cladding. The type of oxidant and temperature-dependent catalytic degradation of six azo dyes and detoxification of hexavalent chromium [Cr (VI)] was studied. The as-synthesized PdNPs-catalyst demonstrate excellent performance in the formic acid (HCOOH)-induced catalytic reduction of such pollutants with the optimum at 45 degrees C temperature. We are optimistic that the insights on the behavior of reactant adsorption and reaction kinetics revealed in this study could be readily extended to other reaction systems and practically applied to wastewater treatment.