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Structural and electrochemical properties of bismuth ferrite nanostructures produced by pulsed laser deposition with various morphologies are reported. The nanostructures are also explored as electrode materials for high-performance supercapacitors. Scanning electron microscopy images revealed that various bismuth ferrite morphologies were produced by varying the background pressure (10−6, 0.01, 0.10, 0.25, 0.50, 1.0, 2.0 and 4.0 Torr) in the deposition chamber and submitting them to a thermal treatment after deposition at 500 ◦C. The as-deposited bismuth ferrite nanostructures range from very compact thin-film (10−6, 0.01, 0.10 Torr), to clustered nanoparticles (0.25, 0.50, 1.0 Torr), to very dispersed arrangement of nanoparticles (2.0 and 4.0 Torr). The electrochemical characteristic of the electrodes was investigated through cyclic voltammetry process. The increase in the specific surface area of the nanostructures as background pressure in the chamber increases does not lead to an increase in interfacial capacitance. This is likely due to the wakening of electrical contact between nanoparticles with increasing porosity of the nanostructures. The thermal treatment increased the contact between nanoparticles, which caused an increase in the interfacial capacitance of the nanostructure deposited under high background pressure in the chamber. [ABSTRACT FROM AUTHOR]

An electrode modified with phytic acid (PA)-doped polypyrrole (PPy)/molybdenum disulfide (MoS2) nanocomposites for the simultaneous detection of Pb2+ and Cd2+ heavy metal ions in water. On the surface of MoS2 nanosheets PA-doped PPy/MoS2 nanomaterials were fabricated by in situ chemical oxidation polymerization. The PA-doped PPy network was uniformly covered the surface of MoS2 nanosheets which can improve stability of MoS2 and increase electrochemical active sites. The PA-doped PPy/MoS2-modified electrode demonstrated outstanding electrochemical performance compared to the PA-doped PPy and MoS2-modified electrodes. The PA-doped PPy/MoS2 has been proven to detect range of Pb2+ and Cd2+ between 10 and 300 μg/L. The limit of detection (LOD = 3σ/k) for Pb2+ was 1.78 μg/L and for Cd2+ was 2.03 μg/L. The PA-doped PPy/MoS2-modified electrode has good selectivity, reproducibility and stability. In practical tap water applications, good recoveries were achieved. This work illustrated a straightforward, helpful and high performing pathway within the areas of electrochemical detecting Pb2+ and Cd2+. [ABSTRACT FROM AUTHOR]

Here we report a novel electrochemical sensor based on Barium titanate / reduced graphene oxide nanocomposite (BaTiO3/rGO) for precise detection of 4-nitrophenol and Dopamine. The electrochemical characteristics of both analytes were studied using a glassy carbon electrode (GCE) modified with a BaTiO3/rGO composite film. Incorporating reduced graphene oxide (rGO) sheets with BaTiO3 nanoparticles notably improved the electrochemical reactivity of these analytes. The modified electrochemical sensor exhibits a wide linear detection range of 5 to 50 µM for 4-nitrophenol, with a remarkably low detection limit of 0.44 µM. Similarly, dopamine detection demonstrates consistent linearity spanning from 2.5 to 50 µM, with an impressive detection limit of 0.08 µM. Real-world assessments using tap water and human urine samples underscore the exceptional recovery results, highlighting its practical utility. [ABSTRACT FROM AUTHOR]

Although high-temperature solid-phase methods have become the dominant route for manufacturing layered oxide cathode materials in industry, severe Li+/Ni2+ cation mixing problems caused by high-temperature processes still prevent the realization of high-performance lithium-ion batteries. Herein, a wet chemical lithiation method by stepwise lithium intercalation to reduce and shorten the sintering temperature and time of the post-treatment process is proposed. Li 0.6 H x Ni 0.52 Co 0.19 Mn 0.29 O 2 stepwise products with lithiation efficiencies exceeding 60% were obtained at reaction temperatures below 200 °C. The as-prepared LiNi 0.52 Co 0.19 Mn 0.29 O 2 (HT-52-S) exhibits low Li+/Ni2+ cation mixing and good comprehensive electrochemical performance after subsequent heat treatment to complete all lithiation. Compared with LiNi 0.52 Co 0.19 Mn 0.29 O 2 (SS-52) prepared by the conventional high-temperature solid-phase method, the Li+/Ni2+ cation mixing of HT-52-S was relatively reduced by 57.9%, and the capacity retention after 100 cycles at 1 C was relatively improved by 22.1%. We believe that this work can serve as a useful reference to develop manufacturing processes for high-performance layered oxide cathode materials. [ABSTRACT FROM AUTHOR]

The work presented an electrochemical anode method with different electrolyte concentrations and heat posttreatment to control the stoichiometry and structure of Cu2−xS electrocatalysts. X‐ray diffraction, X‐ray photoelectron spectroscopy, and scanning electron microscopy were employed to characterize the composition and morphology, whereas the electrocatalytic activity was evaluated by linear scanning voltammetry and electrochemical impedance spectroscopy. The results showed that the electrochemical method successfully synthesized thin flake‐shaped Cu7S4, which exhibited optimal performance at the electrolyte concentration of 0.45 mol L1 with maximum turnover frequency of 0.786 s−1, maximum mass activity of 0.539 A g−1, minimum charge transfer resistance of 0.156 Ω cm−2, and minimum overpotential of 154 mV at a current density of 10 mA cm−2. In the Cu7S4 structure, Cu2+ and S2− were coordinated in a CuS4 tetrahedral structure, whereas Cu+ and S2− were coordinated in a CuS3 triangular structure. Heat posttreatment could change the stoichiometry from 1.75 to 1.8 and improve the electrochemical performance. In the Cu9S5 structure, the CuS3 triangular structure had disappeared. Under the same conditions, the overvoltage was only 128 mV. [ABSTRACT FROM AUTHOR]

[Display omitted] • Functional doping elements with no unpaired electrons and strong Me-O bond. • Al/Zr co-doping inhibits Li+/Ni2+ mixing and coexistence of H1 and H2 phases. • Al/Zr co-doping inhibits undesired H3 phase generation and lattice oxygen loss. • An excellent high-voltage medium-nickel low-cobalt LiNi 0.6 Co 0.05 Mn 0.35 O 2 cathode. High-voltage medium-nickel low-cobalt lithium layered oxide cathode materials are intriguing for lithium-ion batteries (LIBs) applications because of their relatively low cost and high capacity. Unfortunately, high charging voltage induces bulk layered structure decline and interface environment deterioration, low cobalt content reduces lithium diffusion kinetics, severely limiting the performance liberation of this kind of cathode. Here, a multifunctional Al/Zr dual cation doping strategy is employed to enhance the electrochemical performance of LiNi 0.6 Co 0.05 Mn 0.35 O 2 (NCM) cathode at a high charging cut-off voltage of 4.5 V. On the one hand, Al/Zr co-doping weakens the Li+/Ni2+ mixing through magnetic interactions due to the inexistence of unpaired electrons for Al3+ and Zr4+, thereby increasing the lithium diffusion rate and suppressing the harmful coexistence of H1 and H2 phases. On the other hand, they enhance the lattice oxygen framework stability due to strong Al-O and Zr-O bonds, inhibiting the undesired H2 to H3 phase transition and interface lattice oxygen loss, thereby enhancing the stability of the bulk structure and cathode-electrolyte interface. As a result, Al/Zr co-doped NCM (NCMAZ) shows a 94.2 % capacity retention rate after 100 cycles, while that of NCM is only 79.4 %. NCMAZ also exhibits better rate performance than NCM, with output capacities of 92 mAh/g and 59 mAh/g at a high current density of 5C, respectively. The modification strategy will make the high-voltage medium-nickel low-cobalt cathode closer to practical applications. [ABSTRACT FROM AUTHOR]

Tin disulfide (SnS2) is a highly promising anode material for sodium-ion batteries (SIBs) due to its substantial theoretical capacity stemming from alloying reactions and conversion mechanisms. Eliminating non-conductive binders and simplifying fabrication, the binder-free SnS2@carbon cloth (SnS2@CC) electrode is gaining attention. In this study, a one-step solvothermal synthesis was applied to fabricate binder-free SnS2@CC structures as SIB anodes. The electrochemical performance was enhanced by doping copper (Cu) into the SnS2 lattice. Solvothermal duration and Cu doping levels were systematically investigated to optimize the electrochemical properties of anodes. The Cu-doped SnS2@CC (Cu–SnS2@CC) electrodes exhibited superior electrical conductivity and sodium ion diffusion coefficients compared to those for the SnS2@CC electrodes. After 30 cycles, the Cu–SnS2@CC electrode prepared using a 15-h solvothermal process and 2% Cu doping achieved the highest capacity of 1092.8 mA h g−1 at 0.1 A g−1, while the SnS2@CC electrode yielded only 436.4 mA h g−1 under the same conditions. The optimized Cu–SnS2@CC electrode demonstrates excellent rate performance and cycling stability, with a capacity retention of 63% and Coulombic efficiency of 100% after 130 charge/discharge cycles. This research paves the way for high-performance, binder-free SnS2-based anodes in SIBs. [ABSTRACT FROM AUTHOR]

Battery materials research is of crucial importance to the development of next‐generation batteries. However, the transition from lab‐scale studies, typically in gram quantities, to industrially relevant ones (i.e., kilogram scale) has been holding back by challenges in scale‐up synthesis and a lack of reliable approaches to verify the electrochemical performance of the lab‐made materials. Here the design and assembly procedures of sub‐Ah‐scale pouch cells that provide validations of several lab‐made Li‐ion and Na‐ion cathode materials available in a limited quantity (<5 g) are reported. These lab‐made pouch cells show superior cycle stability and consistency over the widely used coin cells, exemplified by multiple Ni‐rich layered oxide‐graphite full batteries retaining 84.29 ± 0.16% of the initial capacities over 1000 cycles. A four‐electrode pouch cell with a reparable reference electrode is further designed to monitor impedance growth and Li plating during long‐term electrochemical tests. It can be further integrated with in situ ultrasonic imaging to enable multi‐modal studies. This work provides a powerful platform to evaluate and boost the technology readiness levels of laboratory‐discovered battery materials. [ABSTRACT FROM AUTHOR]

The lack of suitable cathode materials has hampered the further development of calcium-ion batteries (CIBs). A novel composite cathode material, namely BaV6O16·3H2O@GO, was fabricated, which delivers a high specific capacity of 285.72 mA h g−1 at 50 mA g−1 after 50 cycles and a long cycle life, benefiting from a large layer spacing and robust structure. This study provides guidance for the development of vanadium-based cathode materials for CIBs. [ABSTRACT FROM AUTHOR]

In this study, high-temperature solid-phase techniques are used to prepare pristine and Mg-modified LiNiO 2 cathode materials. Various characterizations are performed to analyze the morphology, structure, and electrical state of the two materials. Electrochemical tests show that Mg doping effectively improves the electrochemical properties of the materials. In particular, the modified sample exhibits a higher specific discharge capacity of 244.5 mA h g−1 than the pristine sample. Moreover, its maximum capacity retention after 304 cycles at 1 C is 54.1%. In situ X-ray powder diffraction imaging reveals that the modified material has better phase-transition reversibility than the pristine material. Density functional theory calculations indicate that Mg-doped Li sites can accelerate Li+ transport. Atomic force microscopy results demonstrate that Mg-doped Li sites act as supportive skeletons that enhance the mechanical properties of the material. Therefore, the proposed strategy for the Mg doping of Li sites can improve the architecture of LiNiO 2 cathode materials. [ABSTRACT FROM AUTHOR]

Developing sophisticated lithium-ion batteries with high energy and power density requires using high-voltage positive electrodes. Due to its three-dimensional lithium-ion diffusion and greater nominal operating voltage, spinel LiNi 0.5 Mn 1.5 O 4 has emerged as one of lithium-ion batteries' most viable cathode materials. Electrolyte breakdown, Mn dissolution, and rapid cathode-electrolyte interface (CEI) degradation in lithium-ion cells are exacerbated by the high operating voltage of LNMO. Consequently, the long-term cycling of LNMO is hampered by such adverse side effects, making the commercialization of such a battery impractical. Here, we document the enhancement in the electrochemical performance of LNMO by surface modification utilizing a combination of Al 2 O 3 coating and Graphene enveloping employing a facile wet synthesis technique. The presence of highly crystalline spherical secondary microspheres consisting of primary nanoparticles of disordered LiNi 0.5 Mn 1.5 O 4 , the surface modification with Al 2 O 3 , and the subsequent graphene wrapping were all confirmed by structural and surface analysis techniques. The fabricated cells containing the enhanced cathode material (LNMO-Al-GO) were cycled at a C/10 rate for 100 cycles in a voltage window of 3.5–4.9 V, providing a specific discharge capacity of 134.7 ± 3.8 mAhg−1. Delivering a capacity retention of 97.7 ± 3.9% compared to the unmodified LNMO sample (84.7 ± 5.3%). Ex-situ XRD, Electrochemical Impedance Spectroscopy (EIS), and Differential Scanning Calorimetry (DSC) investigations reveal that the alumina coating protects the cathode by acting as a hydrogen fluoride (H.F.) scavenger and minimizes unfavorable phase formations at the CEI, inhibiting Mn3+ dissolution and enhancing cyclability. [ABSTRACT FROM AUTHOR]

Coal fly ash (FA), an aluminum silicate by-product and environmental pollutant which is generated during the combustion of coal in coal-fired power stations, was used as an electrode modifier for the determination of Cd(II) in aqueous solutions. In this work, graphite/polyurethane-based composites containing different amounts of FA were prepared and characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) thermogravimetry (TGA), and derivative thermogravimetry (DTG). The graphite/polyurethane composite electrodes (GPUE), with and without FA modifier, were evaluated with regard to their performance as voltammetric electrodes in the determination of metallic cations, using Cd(II) as a probe. After optimizing solution and instrumental parameters affecting the peak current, a differential pulse anode stripping voltammetry (DPASV) procedure was developed for GPUE modified with 5% FA (m/m), resulting in a linear response for Cd(II) from 2.0 x 10−7 to 1.0 x 10−6 mol L−1 with a detection limit (LOD) of 6.6 x 10−8 mol L−1. Cd(II) was added to natural water samples and determined at the 10−7 mol L−1 level with a mean recovery of 99%. It was also extracted from exhausted rechargeable Ni-Cd batteries and diluted to ca. 0.2 µmol L−1 and determined with the same electrode, with recoveries of 98.7% when compared to FAAS. These results serve as a proof of concept that FA is a useful electrode modifier. [ABSTRACT FROM AUTHOR]

A simple and reliable method based on a composite of Nafion (Naf), multiwalled carbon nanotubes (MWCNTs), and mesoporous silica (SBA-15) modified glassy carbon electrode (GCE) is reported for individual and simultaneous determination of indigo carmine (IC, dye) and carbendazim (CBZ, pesticide). SBA-15 was synthesized and characterized and used to design a GCE/Naf/MWCNTs/SBA-15 sensor, which was characterized by electrochemical techniques and used for the determination of IC and CBZ. Using the optimum conditions for differential pulse voltammetry (DPV), the peak currents were linear from 1.0 µM to 11.0 µM. The limits of detection for individual measurements were 0.50 µM and 0.57 µM for IC and CBZ, respectively, while those for simultaneous detection were 0.28 µM and 0.30 µM. The interferences studies show that GCE/Naf/MWCNTs/SBA-15 exhibited excellent selectivity. The developed procedure was successfully applied to determine IC and CBZ in spring, tap, and lake water. [ABSTRACT FROM AUTHOR]

[Display omitted] • PO 4 3−-doping and Li 3 PO 4 -coating of dual modification of LiNiO 2 are achieved. • PO 4 3− doping improves the reversibility of crystal structure. • PO 4 3− doping induces surface structural transformation of the material. • Li 3 PO 4 coating could ameliorate the interface stability. Lithium nickel oxide (LiNiO 2) cathode materials are featured with high capacity and low cost for rechargeable lithium-ion batteries but suffer from severe structure and interface instability. Bulk doping together with surface coating has been proven to be an efficient approach to improve the inner structure and interfacial stability of the LiNiO 2 cathode material. Nevertheless, the role of anion doping seems to be quite different from that of cation doping, and a deep insight will be desirable for the structure design of the LiNiO 2 cathode material. In this paper, PO 4 3−-doped and Li 3 PO 4 -coating of dual modification of LiNiO 2 are achieved via a facile approach. It is demonstrated that the PO 4 3− anions are doped into the tetrahedron vacant sites of the crystal structure, alleviating the phase transition and improving the reversibility of crystal structure. Besides, the Li 3 PO 4 coating layer ameliorates the interface stability to restrain the side reactions. Therefore, the dual modification enhances overall structural stability of the material to provide excellent performance. Moreover, the consumption of the Li residues by the formation of Li 3 PO 4 coating layer, and the enlarged interlayer spacing of the crystal structure by PO 4 3− doping can facilitate the Li+ ions diffusion, resulting in a superior rate capability. [ABSTRACT FROM AUTHOR]

Two‐dimensional (2D) metal–organic frameworks (MOFs) have been a worldwide research interest due to their potential application in supercapacitors. Herein, a cobalt‐based layered MOF ([Co2(μ‐SO4)(Hppza)2(H2O)3]n, namely, SEU‐1; H2ppza=3‐(pyridin‐4‐yl)‐1H‐pyrazole‐5‐carboxylic acid) has been synthesized via a one‐step solvothermal method. Single X‐ray diffraction analysis shows that the SEU‐1 exhibits a (3,3,4)‐connected 2D structure with a Schläfli symbol of (62 ⋅ 8)(63)(64 ⋅ 8 ⋅ 10). Variable‐temperature magnetic susceptibility data display that antiferromagnetic interactions between two CoII ions exist in SEU‐1. The supercapacitive performance has been evaluated in the three‐electrode system. Its maximum specific capacitance is 145.5 F g−1 at 1 A g−1, along with the specific capacitance retention of 92.7 % at the current density of 5 A g−1 after 6000 cycles in 3 M KOH solution. These results demonstrate that SEU‐1 is a good candidate for electrode material for electrochemical energy storage. [ABSTRACT FROM AUTHOR]

Electrochemical hydrogen compression is a promising alternative to conventional mechanical compression due to low maintenance costs and high one-stage compression ratios. The typically employed planar systems, however, are intrinsically difficult to operate in high differential pressure environments. Tubular systems are inherently advantageous for high differential pressure systems but require innovative membrane electrode assembly development. This study unveils the first tubular EHC featuring a membrane electrode assembly supported by a stainless steel 3D-printed porous anode. The membrane electrode assembly for gas-phase electrochemistry is produced by spray coating the porous anode with Pt/C as the catalyst and joining the anode with a tubular catalyst-coated membrane. Electrochemical characterization demonstrates the functionality of the tubular EHC at current densities up to 60 mAcm − 2 with a cell potential of 200 mV under non-pressurized conditions. Moreover, a pressure difference of 2 bar is achieved at 60 mAcm − 2 within the first 60 min in continuous mode. By demonstrating the proof-of-principle for the first tubular EHC, this work paves the way for new research avenues in electrochemical process engineering, offering a broad spectrum of applications, from enhancing EHC technologies to advancing electrochemical CO 2 reduction. • Tubular membrane electrode assembly for electrochemical hydrogen compression. • Metal 3D-printed tubular electrode with tunable porosity. • Electrochemical characterization of tubular module. • A maximum hydrogen compression of 2 bar at current densities up to 60 mA/cm2. [Display omitted] [ABSTRACT FROM AUTHOR]

The practical utilization of Li metal anodes has been significantly plagued by the challenges of uncontrollable dendritic Li growth and poor interphase instability. Here, the study reports a novel strategy to strengthen interphase and give highly efficient active seeds concurrently to stabilize Li metal via a highly lithiophilic In2O3 decorated porous scaffold. In situ configurated fast‐ion‐transport Li2O‐strengthened interphase layer cooperatively with highly efficient Li13In3 nucleation induction can endow the uniform Li nucleation/growth and high Li utilization efficiency. As a result, the achieved modified Li metal manifests high Coulombic efficiency, ultrahigh rate performance (5 mA cm−2), and ultra‐long lifespan cycling durability (7975 cycles). Importantly, the established Li|LiFePO4 cells exhibit long‐term cycling durability over 600 cycles at 1 C with an ultralow decay rate of ca. 0.017% per cycle. Moreover, the Li|LiCoO2 pouch cells with ultrahigh areal capacity of ca. 3.89 mAh cm−2 also exhibit extraordinarily prolonged cycling performance with excellent capacity retention despite extremely harsh cycling conditions of low negative‐to‐positive‐capacity (N/P) ratio of ca. 1.7 and lean electrolyte of ca. 4.9 g Ah−1. This work enlightens a facile and effective avenue toward highly stable Li metal anode toward reliable practicability. [ABSTRACT FROM AUTHOR]

The reduction of carbon dioxide (CO2) using porphyrin‐containing 2D covalent organic frameworks (2D‐COFs) catalysts is widely explored nowadays. While these framework materials are normally fabricated as powders followed by their uncontrolled surface heterogenization or directly grown as thin films (thickness >200 nm), very little is known about the performance of substrate‐supported single‐layered (≈0.5 nm thickness) 2D‐COFs films (s2D‐COFs) due to its highly challenging synthesis and characterization protocols. In this work, a fast and straightforward fabrication method of porphyrin‐containing s2D‐COFs is demonstrated, which allows their extensive high‐resolution visualization via scanning tunneling microscopy (STM) in liquid conditions with the support of STM simulations. The as‐prepared single‐layered film is then employed as a cathode for the electrochemical reduction of CO2. Fe porphyrin‐containing s2D‐COF@graphite used as a single‐layered heterogeneous catalyst provided moderate‐to‐high carbon monoxide selectivity (82%) and partial CO current density (5.1 mA cm−2). This work establishes the value of using single‐layered films as heterogene ous catalysts and demonstrates the possibility of achieving high performance in CO2 reduction even with extremely low catalyst loadings. [ABSTRACT FROM AUTHOR]

Despite the enormous efforts to control the growth behavior of Li, achieving a dendrite‐free Li deposition and high‐energy‐density have remained an inevitable challenge of Li metal batteries. Here, the conformal deposition of Li metal is reported on electroactive organic materials to achieve a high‐energy‐density and electrochemical longevity. To this end, Li2C8H4O4 (Li2TP), which can act as both the electrode material (providing the redox capacity) and Li host (inducing the dendrite‐free Li deposition), is used as the model electroactive organic material. The Li2TP host exhibits reversible sequential lithiation/delithiation and Li deposition/stripping reactions. Consequently, a Li‐free full cell constructed by the Li2TP host (without pre‐charging) and a LiFePO4 cathode delivered a high areal capacity (≈3.8 mAh cm−2), exceptional rate performance (≤12 mA cm−2), and superior cyclability (80% capacity retention after 100 cycles). This electroactive organic material‐based Li host strategy can provide a new perspective for the development of practical Li metal batteries. [ABSTRACT FROM AUTHOR]

Li‐ and Mn‐rich layered oxides (LMROs) are promising cathode materials for next‐generation lithium‐ion batteries (LIBs) due to their high capacity and high energy density. However, they suffer from severe capacity and voltage fading during cycling, where the irreversible oxygen release during cycle is deemed to a severe factor. Herein, this put forward a general oxygen release suppression strategy by introducing small amounts of sodium chalcogenides during cathode slurry preparation. The formed unstable surface peroxide ions O22− of LMRO during charging is reduced to stable O2− by chalcogen ion and couples the formation of sodium chalcogenic oxides, which is reduced to sodium chalcogenides and O2− during discharging. As a result, the oxygen release is significantly suppressed and the structural stability of LMRO is greatly enhanced. Meanwhile, abundant surface oxygen vacancies are generated coupling with evidently increased carrier concentration and mobility, thus enhancing electronic conductivity significantly. The Li1.2Ni0.13Co0.13Mn0.54O2 cathode with 3 wt% Na2Se shows a capacity retention as high as 96.2% and a capacity of 225 mAh g−1 after 500 cycles at 1 C, coupling with a high capacity of 135 mAh g−1 at 10 C. The relevant mechanism for the improved electrochemical properties is revealed, which is hopefully helpful for novel strategy design to high‐performance LMRO cathodes. [ABSTRACT FROM AUTHOR]

The electrolyte concentration not only impacts the battery performance but also affects the battery cost and manufacturing. Currently, most studies focus on high‐concentration (>3 M) or localized high‐concentration electrolytes (~1 M); however, the expensive lithium salt imposes a major concern. Most recently, ultralow concentration electrolytes (<0.3 M) have emerged as intriguing alternatives for battery applications, which feature low cost, low viscosity, and extreme‐temperature operation. However, at such an early development stage, many works are urgently needed to further understand the electrolyte properties. Herein, we introduce an ultralow concentration electrolyte of 2 wt % (0.16 M) lithium difluoro(oxalato)borate (LiDFOB) in standard carbonate solvents. This electrolyte exhibits a record‐low salt/solvent mass ratio reported to date, thus pointing to a superior low cost. Furthermore, this electrolyte is highly compatible with commercial Li‐ion materials, forming stable and inorganic‐rich interphases on the lithium cobalt oxide (LiCoO2) cathode and graphite anode. Consequently, the LiCoO2‐graphite full cell demonstrates excellent cycling performance. Besides, this electrolyte is moisture‐resistant and effectively suppresses the generation of hydrogen fluoride, which will markedly facilitate the battery assembly and recycling process under ambient conditions. [ABSTRACT FROM AUTHOR]

The electrolyte concentration not only impacts the battery performance but also affects the battery cost and manufacturing. Currently, most studies focus on high‐concentration (>3 M) or localized high‐concentration electrolytes (~1 M); however, the expensive lithium salt imposes a major concern. Most recently, ultralow concentration electrolytes (<0.3 M) have emerged as intriguing alternatives for battery applications, which feature low cost, low viscosity, and extreme‐temperature operation. However, at such an early development stage, many works are urgently needed to further understand the electrolyte properties. Herein, we introduce an ultralow concentration electrolyte of 2 wt % (0.16 M) lithium difluoro(oxalato)borate (LiDFOB) in standard carbonate solvents. This electrolyte exhibits a record‐low salt/solvent mass ratio reported to date, thus pointing to a superior low cost. Furthermore, this electrolyte is highly compatible with commercial Li‐ion materials, forming stable and inorganic‐rich interphases on the lithium cobalt oxide (LiCoO2) cathode and graphite anode. Consequently, the LiCoO2‐graphite full cell demonstrates excellent cycling performance. Besides, this electrolyte is moisture‐resistant and effectively suppresses the generation of hydrogen fluoride, which will markedly facilitate the battery assembly and recycling process under ambient conditions. [ABSTRACT FROM AUTHOR]

[Display omitted] Co-free Ni-rich single crystal LiNi x Mn 1-x O 2 (x ≥ 0.6) (denoted as SCNM) have been actively studied as a candidate cathode for high energy density and low-cost lithium-ion batteries (LIBs). However, their practical use in LIBs is significantly hindered by their poor chemo-mechanical stability and short cycle life. Herein, we show much improved structural stability and cycle life by bulk and surface modifications of SCNM. We show strong evidence that bulk Ti-doping and gradient Nb-doping are effective in stabilizing lattice oxygen and suppressing detrimental phase transformations, while LiTi 2-x Nb x (PO 4) 3 (LTNP) surface coating protects SCNM from reacting with liquid electrolyte and promotes formation of thin and robust interphase layers. As a result, LTNP-modified SCNM achieves an excellent electrochemical performance with 87.2% capacity retention after 100 cycles at high voltage of 4.4 V. This work demonstrates a new approach to stabilize lattice oxygen of Co-free and Ni-rich cathodes and their interfaces with liquid electrolytes, thus contributing to the development of high-energy–density LIBs. [ABSTRACT FROM AUTHOR]

Lead (Pb2+), due to its non‐biodegradable property and biological accumulation, would have adverse effects on human body. In this study, a poly(pyrrole thiourea) modified electrode was developed using the electropolymerization of pyrrole and thiourea. Compared with drop‐casting method, the immobilization of the modified material with fixator and the modification efficiency of an electrode was improved. The poly(pyrrole thiourea) electrode was applied for the in‐situ determination of Pb2+ in water coupled with an electrochemical flow analysis device. Several experimental parameters were optimized and the interference of the common co‐existing ions were evaluated. The precision and the repeatability of the electrode‐modified method were also examined. The relative standard deviation of response currents to 20 μg L−1 Pb2+ was found to be 4.6 % (n=90) and the recoveries varied from 91.6 % to 110.2 % in the determination of tap water and lake water samples obtained from laboratories and the university campuses. The limit of detection (3σ/Slope) of 0.03 μg L−1 for Pb2+ within the range of 0.1–100 μg L−1. Finally, the continuous monitoring of Pb2+ in water was successfully done by this developed method. [ABSTRACT FROM AUTHOR]

A new family of two‐dimensional (2D) transition metal carbides, carbonitrides, and nitrides (MXenes) has attracted increasing attention owing to their electrical, chemical, and physical properties. Together with various attractive properties of the MXenes, they also exhibit electrochemical induced deformation (i.e., expansion/contraction) via ion intercalation/de‐intercalation in/from MXene layers. In this respect, MXenes offer the possibility of application as the electrode of electrochemical actuators (ECAs). While the MXene‐based ECAs are still in their infancy stage, researchers have made great effort to achieve high‐performance MXene‐based electrochemical capacitors (ECs). As the name suggests, both ECAs and ECs shared common traits in which their operations are based on electrochemical processes. This review provides the recent progress in the MXene‐based ECAs in parallel with that in the MXene‐based ECs to gain insights from the relatively mature developments in EC applications. Finally, based on the findings from previous studies on both electrochemical applications, perspectives on future MXene‐based ECAs in terms of electrode, electrolyte, and cell configuration are provided. [ABSTRACT FROM AUTHOR]

Owing to the higher global energy needs through cleaner sources the present study manifests a modified and ecofriendly method for the fabrication of CuO–Sb2O3-based electrode for electrochemical experiments. The aqueous solution derived from the Amaranthus viridis L. plant, belonging to the Amaranthaceae family, was employed as a reducing agent in order to impact the structure of CuO–Sb2O3 nanocomposites. The improved material exhibited a regular crystal size of 40.04 nm that is in excellent accordance with the findings obtained from scanning electron microscopy (SEM). Fourier-transform infrared spectroscopy, FE-SEM, and energy-dispersive spectroscopy were utilized in order to examine and assess the synthesized nanocomposite. Based on the Tauc plot, the optical bandgap energy was found to be 2.7 eV. The bioorganic framework-derived CuO–Sb2O3 electrode was then evaluated for energy generation and storage applications, with cyclic voltammetry revealing a capacitance of 344.4 F/g at 2 mV/s. Hydrogen evolution reaction and oxygen evolution reactions demonstrated the electrocatalytic potential of CuO–Sb2O3 as a water splitting electrocatalyst, with the highest efficiency of the electrode up to 18 h for HER. [ABSTRACT FROM AUTHOR]

A novel electrochemical sensor for paraquat determination was facilely developed using nanocomposites of cellulose incorporated with manganese oxide (MnO2@cellulose) modified screen-printed carbon electrode (SPCE). In this study, SPCE was fabricated on a low-cost poster paper, and nanocellulose from sugarcane bagasse was employed to enhance the electrode's surface area and improve the dispersion of MnO2. The MnO2@cellulose modified poster-SPCE exhibited a high electrochemical response toward paraquat. Various influencing factors, including differential pulse voltammetric parameters and accumulation time, were systematically explored. Under the optimal conditions, the cathodic peak current was linearly proportional to paraquat concentration in a range of 2 to 200 µM, featuring a low detection limit of 1 µM. The proposed sensor offers cost-effectiveness and can be readily prepared via a simple procedure. Moreover, this method exhibits excellent reproducibility, high selectivity, and a short analysis time. The portable electrochemical sensor was able to determine paraquat in water samples with acceptable recoveries from 95.45 to 109.20%, indicating that the sensor based on MnO2@cellulose/SPCE is reliable for paraquat quantification. [ABSTRACT FROM AUTHOR]

Antimony selenide (Sb 2 Se 3) is considered an ideal anode material candidate for sodium-ion batteries (SIBs) due to its abundant resources, low bandgap, and high theoretical capacity. However, the big volume changes, poor structural stability, and slow dynamics have led to rapid capacity decay and severely limited its application in large-scale energy storage. To resolve these problems, we designed a rod-shaped Sb 2 Se 3 composite material coated with Co and Sb bimetallic selenides using a one-pot hydrothermal method (CoSb 2 Se 4 @Sb 2 Se 3) to activate the redox reaction of SIBs anode. The presence of a suitable Co content coating layer (2CSS) enables Sb 2 Se 3 to adapt to volume expansion during cycling, thereby improving structural and cycling stability. After 160 cycles under 1 A g−1 conditions, the capacity retention rate is 81.4%. 2CSS also exhibits rapid ion diffusion ability and efficient Na+ storage capacity, which is beneficial for improving rate performance. Even at 10 A g−1, it can provide a reversible discharge capacity of 222.2 mAh g−1. A series of electrochemical performance tests strongly demonstrate that coatings can better utilize the capacity advantage of alloy electrodes to improve electrochemical performance. This work provides an effective strategy for constructing high-performance cathode materials for SIBs. [ABSTRACT FROM AUTHOR]

The continuous development of portable devices and new energy vehicles has led to an increasing demand for high‐performance lithium‐ion batteries (LIBs), and anode materials, as a key part of LIBs, are being explored. Germanium‐based anode materials are considered to have good potential for application because of their high theoretical capacity. In this work, a germanium phosphate glass precipitating GeO2 microcrystal was designed and used in LIBs as anode materials for the study. The presence of GeO2 crystals increases the specific surface area and also provides more reaction sites for lithiation reaction, resulting in the capacity of the glass anode. The discharge specific capacity of the germanium‐phosphorus glass anode was as high as 740.9 mAh g−1 after 600 cycles at a current density of 500 mA g−1. Interestingly, the synergistic effect between the glass matrix and the crystals not only increases the cycling capacity but also enhances the cycling stability of the structure. [ABSTRACT FROM AUTHOR]

[Display omitted] • Aluminum doped Co-free cathodes are successfully synthesized using Laminar-Taylor Flow reactor. • Removing cobalt from cathode materials aggravates structural irreversibility and phase transformation, leading to an initial irreversible capacity and reduced cyclability. • In-situ doping of aluminum into Co-free cathodes effectively counters these adverse effects, enhancing structural reversibility and reducing detrimental strain during charge and discharge cycles. • Co-free, Al doped NMA-3 undergoes less amounts of stress compared to NCA-0 cathode material as found from Ag-source in-situ transmission XRD analysis. • Aluminum integration boosts performance and stability, even at high charging rates, with NMA-3 showing excellent retention. (88% retention at 1C after 200 cycles and 71% at 10C for NMA-3). The growing use of EVs and society's energy needs require safe, affordable, durable, and eco-friendly high-energy lithium-ion batteries (LIBs). To this end, we synthesized and investigated the removal of Co from Al-doped Ni-rich cathode materials, specifically LiNi 0.9 Co 0.1 Al 0.0 O 2 (NCA-0), LiNi 0.9 Mn 0.1 Al 0.0 O 2 (NMA-0), LiNi 0.9 Mn 0.07 Al 0.03 O 2 (NMA-3), intending to enhance LIB performance and reduce the reliance on cobalt, a costly and scarce resource. Our study primarily focuses on how the removal of Co affects the material characteristics of Ni-rich cathode material and further introduces aluminum into the cathode composition to study its impacts on electrochemical properties and overall performance. Among the synthesized samples, we discovered that the NMA-3 sample, modified with 3 mol% of Al, exhibited superior battery performance, demonstrating the effectiveness of aluminum in promoting cathode stability. Furthermore, the Al-modified cathode showed promising cycle life under normal and high-temperature conditions. Our NMA-3 demonstrated remarkable capacity retention of ∼ 88 % at 25 °C and ∼ 81 % at 45 °C after 200 cycles at 1C, within a voltage range of 2.8–4.3 V, closely matching the performances of conventional NCM and NCA cathodes. Without cobalt, the cathodes exhibited increased cation disorder leading to inferior rate capabilities at high C-rates. In-situ transmission XRD analysis revealed that the introduction of Al has reduced the phase change and provided much-needed stability to the overall structure of the Co-free NMA-3. Altogether, the findings suggest that our aluminum-modified NMA-3 sample offers a promising approach to developing Co-free, Ni-rich cathodes, effectively paving the way toward sustainable, high-energy–density LIBs. [ABSTRACT FROM AUTHOR]

[Display omitted] • LiNi 0.92 Co 0.04 Mn 0.04 O 2 were synthesized using a novel Taylor–Couette Reactor. • Ta-modified LiNi 0.92 Co 0.04 Mn 0.04 O 2 shows a bifunctional effect via a controlling suitable amount of Ta and Li-salt. • Ta allows tailoring the primary particles' microstructure, and morphology and forming a coating layer. • The experimental results and DFT calculations were combined to study its effect on the electrochemical performance. • Ta-modified LiNi 0.92 Co 0.04 Mn 0.04 O 2 shows excellent electrochemical performance, allowing its EV applications. A novel scalable Taylor–Couette reactor (TCR) synthesis method was employed to prepare Ta-modified LiNi 0.92 Co 0.04 Mn 0.04 O 2 (T-NCM92) with different Ta contents. Through experiments and density functional theory (DFT) calculations, the phase and microstructure of Ta-modified NCM92 were analyzed, showing that Ta provides a bifunctional (doping and coating at one time) effect on LiNi 0.92 Co 0.04 Mn 0.04 O 2 cathode material through a one-step synthesis process via a controlling suitable amount of Ta and Li-salt. Ta doping allows the tailoring of the microstructure, orientation, and morphology of the primary NCM92 particles, resulting in a needle-like shape with fine structures that considerably enhance Li+ ion diffusion and electrochemical charge/discharge stability. The Ta-based surface-coating layer effectively prevented microcrack formation and inhibited electrolyte decomposition and surface-side reactions during cycling, thereby significantly improving the electrochemical performance and long-term cycling stability of NCM92 cathodes. Our as-prepared NCM92 modified with 0.2 mol% Ta (i.e., T2-NCM92) exhibits outstanding cyclability, retaining 84.5 % capacity at 4.3 V, 78.3 % at 4.5 V, and 67.6 % at 45 ℃ after 200 cycles at 1C. Even under high-rate conditions (10C), T2-NCM92 demonstrated a remarkable capacity retention of 66.9 % after 100 cycles, with an initial discharge capacity of 157.6 mAh g−1. Thus, the Ta modification of Ni-rich NCM92 materials is a promising option for optimizing NCM cathode materials and enabling their use in real-world electric vehicle (EV) applications. [ABSTRACT FROM AUTHOR]

Designing electrocatalysts that can effectively couple hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) to achieve superior overall water splitting (OWS) is essential, but still a tremendous challenge. Herein, two complementary OER and HER electrocatalysts with nanoarray heterojunction (P–CoN/CWO/Co 3 O 4 /NF nanowire and P–CoN/CMO/Co 3 O 4 /NF nanosheet) were designed by combining the concepts of multi-interface engineering and element doping. Benefiting from the regulation of the electronic environment of the metal center by multi-heterointerfaces and phosphorus doping, the two electrocatalysts possess excellent OER/HER activity in 1.0 M KOH, respectively. For OER, P–CoN/CWO/Co 3 O 4 /NF exhibits an ultra-low overpotential (η 10 = 175 mV) and superior long-term durability (≥80 h) at a current density of 10 mA cm−2. For HER, P–CoN/CMO/Co 3 O 4 /NF appears a desired overpotential (η 10 = 109 mV) and remarkable long-term durability (≥110 h). Impressively, the P–CoN/CWO/Co 3 O 4 /NF(+)||P–CoN/CMO/Co 3 O 4 /NF(−) couple constructed with two complementary electrocatalysts exhibits outstanding OWS activity. A low cell voltage of 1.55 V in 1.0 M KOH solution can reach 10 mA cm−2, and it can operate stably at this current density for more than 96 h. The fascinating OWS activity is primarily ascribed to the complementary OER/HER activity demonstrated by the electrocatalysts at the two electrodes of the electrolytic cell, which collectively promote the kinetics of hydrolytic dissociation. This study provides a new approach to develop electrode materials for asymmetric alkaline electrolytic cells with superior overall water splitting performance. Two complementary OER/HER electrocatalysts with nanoarray heterojunction were designed to construct an asymmetric electrolyzer. Benefiting from the effective coupling of OER and HER, the P–CoN/CWO/Co 3 O 4 /NF || P–CoN/CMO/Co 3 O 4 /NF couple displays excellent OWS activity. [Display omitted] • Two nanoarray heterojunctions were designed by interface engineering and element doping. • The new electrocatalysts possess excellent OER/HER activity in 1.0 M KOH, respectively. • P–CoN/CWO/Co 3 O 4 /NF(+) || P–CoN/CMO/Co 3 O 4 /NF(−) exhibits superior OWS activity. [ABSTRACT FROM AUTHOR]

The biomass-derived mesoporous core-shell Fe 3 C@graphene oxide nanospheres (mFe 3 C@GO NSs) was synthesized with high-quality lignins and applied for electrochemical energy storage. The synthesis conditions of mFe 3 C@GO NSs are optimized and its formation mechanism is proposed. The mFe 3 C@GO NSs homogeneously dispersed in GO conductive network and maintained the structural integrity of the electrode during the electrochemical process. Benefiting from the advantages of the core-shell construction and graphene oxide network, the mFe 3 C@GO NSs exhibits extensible exploration in electrochemical energy storage (EES). [Display omitted] • The construction of biomass-derived mFe 3 C@GO NSs by hydrothermal method with lignins. • The mFe 3 C@GO NSs as functional electrodes for electrochemical energy storage. • The effects of mFe 3 C@GO NSs structure on electrochemical behavior. [ABSTRACT FROM AUTHOR]

High‐capacity Ni‐rich layered oxides are promising cathode materials for fabrication of lithium‐ion batteries (LIBs) with high energy density. However, thermal runaway of LIBs with these cathodes leads to great safety concerns. In this study, single crystalline LiNi0.9Co0.05Mn0.05O2 (NCM‐SC) has been prepared and a flexible optical fiber was buried inside the pouch‐type LIBs with NCM‐SC cathode to in situ study its real‐time temperature evolution during charge/discharge process. NCM‐SC exhibits an enhanced Li+ ions transportation efficiency and electrode reaction kinetics, which can effectively reduce the generation of polarization heat and mitigate the internal temperature rise of the pouch‐type battery. Meanwhile, solid‐electrolyte interface (SEI) film decomposition and gas accumulation are effectively alleviated, due to the enhanced thermal stability of SEI film formed on NCM‐SC. Moreover, the single crystal architecture can effectively retard layered to spinal and rock‐salt phase transition, mitigate the crack formation and structural collapse. Consequently, NCM‐SC exhibits an excellent electrochemical performance and enhanced thermal stability. [ABSTRACT FROM AUTHOR]

High‐capacity Ni‐rich layered oxides are promising cathode materials for fabrication of lithium‐ion batteries (LIBs) with high energy density. However, thermal runaway of LIBs with these cathodes leads to great safety concerns. In this study, single crystalline LiNi0.9Co0.05Mn0.05O2 (NCM‐SC) has been prepared and a flexible optical fiber was buried inside the pouch‐type LIBs with NCM‐SC cathode to in situ study its real‐time temperature evolution during charge/discharge process. NCM‐SC exhibits an enhanced Li+ ions transportation efficiency and electrode reaction kinetics, which can effectively reduce the generation of polarization heat and mitigate the internal temperature rise of the pouch‐type battery. Meanwhile, solid‐electrolyte interface (SEI) film decomposition and gas accumulation are effectively alleviated, due to the enhanced thermal stability of SEI film formed on NCM‐SC. Moreover, the single crystal architecture can effectively retard layered to spinal and rock‐salt phase transition, mitigate the crack formation and structural collapse. Consequently, NCM‐SC exhibits an excellent electrochemical performance and enhanced thermal stability. [ABSTRACT FROM AUTHOR]

The development of electrochemical sensors operating at low potentials is a promising method for monitoring environmental toxicants. In this research study, we designed and synthesized a redox active material, ferrocene conjugated biphenyl pyridine acrylonitrile (Fc-BPy), and applied it for the low potential non-enzymatic detection of catechol (CC) through electrochemical technique. Fc-BPy was systematically characterised using single-crystal XRD (SC-XRD). Fc-BPy crystallizes in a triclinic crystal system with a P-1 centrosymmetric space group. The electrochemical investigation of the Fc-BPy/GCE modified electrode exhibits a well-defined redox peak at a low anodic (Epa) and cathodic (Epc) peak potential of 0.32 V and 0.21 V, respectively, which favours the non-interference and selective detection of CC. Furthermore, commendable conductivity was achieved in the absence of any other conducting material due to a profound charge transfer between Fc-BPy and the electrode surface. In amperometry, Fc-BPy/GCE shows excellent non-enzymatic electrocatalytic activity towards CC over a linear detection range from 20 μM to 1.02 mM. The sensitivity and limit of detection (LOD) of CC were found to be 36.42 mM μA−1 cm−2 and 6.2 μM, respectively. Additionally, the fabricated sensor showed consistent performance over multiple cycles and extended periods of storage. The practical utility of the sensor for the detection of CC was tested in various real-time samples. The results were astounding with good recovery rates. Thus, the fabricated sensor exhibits a striking performance for the non-enzymatic detection of CC at a low potential with a high sensitivity, selectivity, better linear range, and low limit of detection. [ABSTRACT FROM AUTHOR]

Paper-based electrochemical sensors have the characteristics of flexibility, biocompatibility, environmental protection, low cost, wide availability, and hydropathy, which make them very suitable for the development and application of biological detection. This work proposes electrospun cellulose acetate nanofiber (CA NF)-decorated paper-based screen-printed (PBSP) electrode electrochemical sensors. The CA NFs were directly collected on the PBSP electrode through an electrospinning technique at an optimized voltage of 16 kV for 10 min. The sensor was functionalized with different bio-sensitive materials for detecting different targets, and its sensing capability was evaluated by CV, DPV, and chronoamperometry methods. The test results demonstrated that the CA NFs enhanced the detection sensitivity of the PBSP electrode, and the sensor showed good stability, repeatability, and specificity (p < 0.01, N = 3). The electrochemical sensing of the CA NF-decorated PBSP electrode exhibited a short detection duration of ∼5–7 min and detection ranges of 1 nmol mL−1–100 μmol mL−1, 100 fg mL−1–10 μg mL−1, and 1.5 × 102–106 CFU mL−1 and limits of detection of 0.71 nmol mL−1, 89.1 fg mL−1, and 30 CFU mL−1 for glucose, Ag85B protein, and E. coli O157:H7, respectively. These CA NF-decorated PBSP sensors can be used as a general electrochemical tool to detect, for example, organic substances, proteins, and bacteria, which are expected to achieve point-of-care testing of pathogenic microorganisms and have wide application prospects in biomedicine, clinical diagnosis, environmental monitoring, and food safety. [ABSTRACT FROM AUTHOR]

The integration of micro/nanostructured metal/metal oxides with carbon-based materials has emerged as a promising approach for developing electrochemical electrodes. However, the fabrication of such hybrids entails complex and multistep procedures involving the grain boundaries and interfaces between the constituent materials, thus, degrading the overall performance. Herein, we report a facile electrothermal process (ETP) for the scalable fabrication of hybrid carbon fiber (CF) sheets integrated with tunable morphology of silver micro/nanoparticles. The application of an electric field across the layered film, consisting of AgNO3 and CF, enabled the rapid dissipation of thermochemical energy in an open-air environment via ETP. The ETP facilitated ultrafast heat dissipation within a few milliseconds, leading to the rapid decomposition of AgNO3, which resulted in the formation of liquefied Ag on the CF surface affording a reduced Ag-CF composite with adjustable structures through input power. The capability of ETP driven by controlling duration and number of electrical pulses was demonstrated by examining the corresponding physiochemical and electrochemical characteristics of the resulting composite. The Ag-CF composite fabricated using three cycles of a screened ETP pulse (1500 W and 75 ms for power and duration) acted as a supercapacitor electrode demonstrating excellent area capacitance (13 F/cm2) and exceptional capacitance retention (98% after 10,000 cycles). Thus, the utilization of ETP can provide manufacturing strategies enabling scalable synthesis of functional hybrids in vacuum-free ambient environments within milliseconds. These hybrids possess unique interfaces and particle boundaries, exhibiting considerable potential for diverse electrochemical applications. [ABSTRACT FROM AUTHOR]

To solve the problem of renewable energy generation fluctuation, water splitting for hydrogen generation is proposed, which can store renewable energy as hydrogen energy. Low overpotential cathode materials can effectively reduce the cost of hydrogen production. Here, a new NiMo/NMF electrode was prepared using a hydrothermal coupled H 2 reduction method. Three-dimensional NiMo nanorod arrays were constructed by modulating the ion dissolution and surface epitaxial growth process of the electrode substrate. The influence of different hydrothermal reaction and H 2 reduction conditions on the electrochemical performance of the electrode was investigated. Under optimum preparation conditions, the NiMo/NMF electrode exhibits a extremely low overpotentials of 158 mV at 500 mA cm-2 (30% wt. KOH alkaline medium), which can serve for preparing high efficiency and economy electrodes by in-situ integration of high active components on metal foam substrate. The NiMo/NMF electrode is a high-performance electrocatalytic cathode material with great prospects for industrial applications. • Water splitting for hydrogen generation is proposed for renewable hydrogen energy. • We made a low-overpotential NiMo/NMF electrode via hydrothermal coupled H 2 reduction. • The electrochemical performance of the NiMo/NMF electrode was investigated. • Different hydrothermal and H 2 reduction temperatures and times were explored. • The NiMo/NMF electrode exhibits a remarkable HER activity with low overpotentials. [ABSTRACT FROM AUTHOR]

Significant technological advancements have been made in the production and utilization of hydrogen (H 2) since 1990, marking the period when its potential as a fuel began to be widely recognized. However, for a hydrogen-based energy system to be viable, especially in the transportation sector, substantial improvements in H 2 storage technology are necessary. Various methods are available for supplying hydrogen to vehicles, including compressed or liquid hydrogen, metal hydrides, chemical storage, and gas adsorption on solid surfaces. Among these, gas-on-solid adsorption emerges as a highly efficient and safe method for storing hydrogen gas. This review briefly summarizes research on hydrogen adsorption using nanostructured adsorbents, such as carbon-based nanostructures (graphene, reduced graphene oxide, carbon nanotubes, carbon nitride, and other carbon nanostructures), metals and metal oxides, polymers, and metal-organic frameworks. Additionally, it covers new experimental and theoretical investigations into the hydrogen adsorption capabilities of metal hydrides. • This review briefly summarizes research on hydrogen adsorption using nanostructured materials. • New experimental and theoretical investigations into the hydrogen adsorption capabilities of metal hydrides are summarized. • Designing electrode materials for H 2 storage devices should focus on improving efficiency, capacity, and practicality. [ABSTRACT FROM AUTHOR]

The effective integration of nanomaterials with underlying current collectors is a key factor affecting the performance of nonenzymatic glucose sensors, where an inappropriate integration structure often leads to poor electron transport and instability. In this work, a seamless integrated electrode was constructed by the in situ immobilizing of a nickel-based metal-organic framework (Ni-MOF) on a three-dimensional (3D) conductive nickel foam (NF) for highly sensitive and durable glucose sensing. Facilitated by a rapid microwave-assisted reaction, a robust interfacial interaction between the Ni-MOF and the substrate was established through in situ conversion from nickel oxide (NiO). The fabricated Ni-MOF/NF electrode exhibits an excellent limit of detection (LOD) of 2.65 μM and an impressive sensitivity (14.31 mA cm-2 mM-1) within the linear range (4-576 μM), which is significantly boosted compared with that of an electrode prepared by a typical drop-casting method (3.56 mA cm-2 mM-1 in 4-1836 μM). Characterization and electrochemical tests reveal that this integrated structure on the one hand contributes to fast electron transport and thus has enhanced sensitivity and on the other hand leads to exceptional durability with its structural integrity maintained under bending, shaking, and ultrasonication. Moreover, this seamless integration method was also employed to immobilize the Ni-MOF converted from the pre-chemically deposited NiO layer on another type of substrate, 3D carbon paper (CP), demonstrating the versatility of this facile strategy in creating diverse electrochemical electrodes for applications beyond glucose sensing. [ABSTRACT FROM AUTHOR]

Bis(diimino)metal complex nanosheets composed of metal ions and hexaaminobenzene ligands (MHABs) are fascinating two-dimensional materials which have been gaining significant attention as electrode materials and electrocatalysts owing to their electrical conductivities, redox properties, and porous structures obtained by the π-conjugated system and regular metal complex arrangement. Although electrochemical oxidation enables the simple and direct formation of MHABs on electrodes within a couple of minutes only, the obtained MHABs are relatively rough and of low crystallinity. This study investigated the effects of the applied potential during the synthesis, the type of base, and the concentrations of bases and building blocks on the synthesis of NiHAB nanosheets. Optical microscopy (OM), atomic force microscopy (AFM), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and grazing-incidence X-ray scattering (GIXS) results revealed that a low oxidation potential, high concentration of the ammonia solution, and low concentration of the building blocks in the reaction solution provided a nanometre-thick NiHAB layer. Under the optimal reaction conditions, NiHAB nanosheets were successfully synthesized in a face-on orientation manner on gold electrodes using electrochemical oxidation methods. Furthermore, the anisotropic electrochemical synthesis of CuHAB was achieved under the optimised conditions. The mechanism of the MHAB growth process with an anisotropic orientation and nanometre thickness was proposed and attributed to the flat adsorption of p-conjugated oligomers composed of bis(diamino)metal moieties in a solution onto an electrode surface and the electrochemical oxidation and deprotonation of the adsorbates on the electrode. [ABSTRACT FROM AUTHOR]

Configuring a carbon substrate with low surface polarity seems very important and significant for accelerating the cathode electrochemical performances of the Lithium-sulfur batteries, which is widely regarded as one of the most promising candidates for the next-generation green energy suppliers. The corn starch-derived carbon with in-situ multi-elements doping, initially carbonized by 6 mol/L H 2 SO 4 and then calcined in nitrogen atmosphere, is employed to configure sulfur cathode for Lithium–Sulfur batteries in this study. As-received carbon with randomly distributed graphical domains serves as charge carriers diffusion channels during discharging/charging cycles, thus endowing the cathode considerable excellent performances. Specifically, the loading amount of sulfur in cathode is around 60.31 wt% and the effective utilization efficiency of active reagent sulfur in cathode is up to 60 %. On activating the cathode at 0.114 A g−1 at 0, 25 and 40 °C, the initial discharge capacities of the Lithium–Sulfur batteries with corn starch-derived carbon-based composite cathode (with ∼1.3 mg cm−2 sulfur) are 278.6, 1023.7 and 976.1 mAh∙g−1, respectively. Accordingly, more uniform, and thinner solid electrolyte interphase membrane formed under room temperature activation, leaving in the dramatically diminished R sur value, contributes to the comparable cycling stability and rate performances of as-designed carbon-based sulfur cathode for Lithium–Sulfur Batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] Hierarchical nanostructures have harvested noteworthy attention lately owing to their remarkable capabilities in the fields of energy storing and transformation, catalysis, and electrical devices. We established an effort less and template-free synthetic method to create hierarchical hetero nanostructures of Zn 2 V 2 O 7 , taking into account the benefits of hierarchical nanostructures, we investigated the performance of HNs (Hierarchical Nanostructures) as electrochemical supercapacitors. Electrochemical tests were tested in a 6 M KOH solution to assess their capabilities. The Zn 2 V 2 O 7 electrode's measured specific capacitance was 750F/g at 1 A/g, with outstanding stability and an excellent retention capacity of 85 % later 5000 cycles in three- electrode electrochemical cells. Asymmetric device such as Zn 2 V 2 O 7 //AC provides a specific capacitance of 76.8F/g at 1 A/g with energy and power densities of 27.3 Wh kg−1 and 800 W kg−1 respectively. The device withstands 85 % of its initial capacity after 5000 continuous GCD cycles at 10 A/g. The outstanding performance observed clearly demonstrates the significant potential and practical utility of Zn 2 V 2 O 7 in the realm of more efficient energy storage applications. [ABSTRACT FROM AUTHOR]

Achieving a high depth of discharge (DOD) in lithium metal anodes (LMAs) is crucial for developing high areal energy density batteries suitable for wearable electronics. Yet, the persistent growth of dendrites compromises battery performance, and the significant lithium consumption during pre‐lithiation obstructs their broad application. Herein, A flexible 3D Li13Sn5 scaffold is designed by allowing molten lithium to infiltrate carbon cloth adorned with SnO2 nanocrystals. This design markedly curbs the troublesome dendrite growth, thanks to the uniform electric field distribution and swift Li+ diffusion dynamics. Additionally, with a minimal SnO2 nanocrystals loading (2 wt.%), only 0.6 wt.% of lithium is consumed during pre‐lithiation. Insights from in situ optical microscope observations and COMSOL simulations reveal that lithium remains securely anchored within the scaffold, a result of the rapid mass/charge transfer and uniform electric field distribution. Consequently, this electrode achieves a remarkable DOD of 87.1% at 10 mA cm−2 for 40 mAh cm−2. Notably, when coupled with a polysulfide cathode, the constructed flexible Li/Li13Sn5@CC||Li2S6/SnO2@CC pouch cell delivers a high‐areal capacity of 5.04 mAh cm−2 and an impressive areal‐energy density of 10.6 mWh cm−2. The findings pave the way toward the development of high‐performance LMAs, ideal for long‐lasting wearable electronics. [ABSTRACT FROM AUTHOR]

In the membrane electrode assembly (MEA) of high-temperature polymer electrolyte membrane fuel cells (HT-PEMFCs), many types of resistance existed, but they have not been distinctly characterized in previous research. In this study, the distribution of relaxation times (DRT) methodology is employed, in conjunction with a home-built electrochemical electrode analysis system (EEAS), to figure out the specific resistance components in the cathode gas diffusion electrode (GDE). The impedance analysis by the DRT method was conducted using the electrochemical impedance spectrum obtained at different temperatures and current densities of the cathode only, isolated from the MEA environment. The four peaks (designated as Peak 0 to 3) were depicted at DRT plots of cathode GDE below 103 Hz. By comparing the DRT plots for different conditions and considering the EEAS structure, the four peaks were explained to be caused by distinct resistances occurring at the electrode and interface. The regions of each peak were distinguished according to their position changes with temperature and current density. Furthermore, by contrasting the DRT plots of the cathode GDE with those of MEA containing the same cathode, an additional peak (referred to as Peak 4) is identified between 103 Hz and 104 Hz, which was attributed to resistance originating from the anode. This study could provide a new approach for future research of new catalysts and electrodes utilizing the resistance analysis of MEA for HT-PEMFC. [Display omitted] • The EEAS was utilized to perform electrochemical analysis of the GDE. • DRT method separates resistances as peaks in the cathode GDE of HT-PEMFCs. • Each peak from the DRT plot is assigned according to the origin of resistance. • Comparative study with MEA differentiates the resistance from electrodes. [ABSTRACT FROM AUTHOR]

Developing non-precious, stable, and highly efficient electrocatalyst materials is crucial for large-scale practical HER applications. Ni3S2 is a prominent catalyst due to its high efficiency and ease of preparation. Nevertheless, its usability is restricted by poor Ni site water molecule adsorption and strong hydrogen bonding between sulphur and hydrogen. The concentration of precursors and samples' morphology significantly affect the electrochemical performance of electrodes intended for the hydrogen evolution reaction (HER) application. This study examines how Mo transition metal sulfide concentration influences the Mo–Co–Ni3S2/NF catalyst's structural aspects and its subsequent electrochemical performance. In situ hydrothermal processing is used to prepare the samples through a two-step process. The samples exhibit enhanced electrocatalytic properties. Specifically, comparatively low overpotentials of 215 mV and 332 mV were observed at current densities of 10 mA cm−2 and 50 mA cm−2, respectively. Additionally, a Tafel slope of 104 mV dec−1 was recorded at a 75 : 25 ratio of molybdenum to cobalt concentration. The samples also demonstrate excellent stability. [ABSTRACT FROM AUTHOR]

Recently, the rock-salt (RS) phases are utilized to enhance the surface stability of LiCoO2 (LCO), however, the optimization mechanism still remains vague. Herein, the structure stability of LCO is successfully enhanced via constructing a tough surface RS layer (≈5 nm), namely, the RS-LCO. This surface RS layer plays a significant role on capturing the migrated lattice O ions upon charging, leading to the progressive phase transition from an inert RS phase to an ionic conductive spinel phase in the surface, and suppresses the bulk H1-3 separation beyond 4.6 V. As a result, not only the oxygen redox induced side reactions are greatly reduced, but also the Li+-ion's transport is significantly promoted. The RS-LCO/Li cells show a remarkable cycle stability with 89.7% capacity retention after 1000 cycles in 3-4.6 V at current of 1 C (1 C = 200 mA g-1), and 81.2% capacity retention after 400 cycles in 3-4.65 V at 1 C. Besides, the RS-LCO/graphite cells show nearly no capacity decay in 600 cycles in 3-4.55 V at 1 C. This work provides a new insight to understand the role of surface RS phase layer on developing the advanced LCO. [ABSTRACT FROM AUTHOR]