Bi-containing Electrolyte Enables Robust and Li Ion Conductive Solid Electrolyte Interphase for Advanced Lithium Metal Anodes

Laser-Scribed Battery Electrodes for Ultrafast Zinc-Ion Energy Storage

Aqueous Zn batteries are promising for large-scale energy storage but are plagued by the lack of high-performance cathode materials that enable high specific capacity, ultrafast charging, and outstanding cycling stability. Here, a laser-scribed nano-vanadium oxide (LNVO) cathode is designed that can simultaneously achieve these properties. The material stores charge through Faradaic redox reactions on/near the surface at fast rates owing to the small grain size of vanadium oxide and interpenetrating 3D graphene network, displaying a surface-controlled capacity contribution (90%-98%). Multiple characterization techniques unambiguously reveal that zinc and hydronium ions co-insert with minimal lattice change upon cycling. It is demonstrated that a high specific capacity of 553 mAh g-1 is achieved at 0.1 A g-1, and an impressive 264 mAh g-1 capacity is retained at 100 A g-1 within 10 s, showing excellent rate capability. The LNVO/Zn can also reach >90% capacity retention after 3000 cycles at a high rate of 30 A g-1, as well as achieving both high energy (369 Wh kg-1) and power densities (56306 W kg-1). Moreover, the LNVO cathode retains its excellent cycling performance when integrated into quasi-solid-state pouch cells, further demonstrating mechanical stability and its potential for practical application in wearable and grid-scale applications.

Smartphone-Integrated Automated Sensor Employing Electrochemically Engineered 3D Bimetallic Nanoflowers for Hydrogen Peroxide Quantification in Milk

Hydrogen peroxide (H2O2), one of the reactive oxygen species in living beings, serves as a regulator of various cellular processes. However, excessive peroxide concentrations are linked to oxidative stress and promptly disrupt cellular components, leading to several pathological conditions in the body. Moreover, it is extremely reactive and has a limited lifetime; thus, H2O2 sensing remains a prominent focus of research. Enzymatic sensing probes were widely employed to detect H2O2 in the recent past; however, they are susceptible to intrinsic chemical and thermal instabilities, which decrease the reliability and durability of the surface. This research was designed to come up with a feasible solution to this problem. Herein, a novel nonenzymatic peroxidase-mimic three-dimensional (3D) bimetallic nanoflower has been synergistically engineered for quick sensing of H2O2. The sensor platform showed minimal resistance or enhanced charge transfer properties as well as remarkable analytical capability, having a broad linear range between 0.01 and 1 nM and a detection limit of 1.46 ± 0.07 pM. The probe responded to changes in H2O2 concentration in just 2.10 ± 0.02 s, making it a quick sensing platform for H2O2 tracking. This peroxidase-mimic nanozyme probe showed minimal sensitivity to interferants often seen in real-world sample matrices and possessed good recoveries ranging from 92.88 to 99.09% in milk samples. Further, a facile and user-friendly smartphone application (APP) named "HPeroxide-Check" was developed and integrated into the sensor to check the milk adulteration by detecting H2O2. It processes the current output obtained from the sensing interface and provides real-time peroxide concentrations in milk. The entire procedure of fabricating the probe is a single, highly robust step that takes only 10 min and is coupled with a smartphone APP, highlighting the sensor's quick manufacturing and deployment for automated H2O2 monitoring in industrial and point-of-care settings.

Advances in Electrochemical Energy Storage over Metallic Bismuth-Based Materials

Bismuth (Bi) has been prompted many investigations into the development of next-generation energy storage systems on account of its unique physicochemical properties. Although there are still some challenges, the application of metallic Bi-based materials in the field of energy storage still has good prospects. Herein, we systematically review the application and development of metallic Bi-based anode in lithium ion batteries and beyond-lithium ion batteries. The reaction mechanism, modification methodologies and their relationship with electrochemical performance are discussed in detail. Additionally, owing to the unique physicochemical properties of Bi and Bi-based alloys, some innovative investigations of metallic Bi-based materials in alkali metal anode modification and sulfur cathodes are systematically summarized for the first time. Following the obtained insights, the main unsolved challenges and research directions are pointed out on the research trend and potential applications of the Bi-based materials in various energy storage fields in the future.

Hybrid Artificial Solid Electrolyte Interphase with Dendrite-Free Lithium Deposition and High Ion Transport Kinetics

Interfacial issues and dendritic Li deposition in lithium metal batteries (LMBs) hamper the practical application of liquid or solid-state cells. Here, a hybrid solid electrolyte interphase (SEI), based on hydroxyl-functionalized boron nitride (BN) nanosheets and poly(vinyl alcohol), is designed to solve the unstable nature of the Li anode-electrolyte interface. Rather than acquiring a rich Li halide environment through intense electrolyte decomposition, the hybrid SEI effectively regulates electrolyte decomposition and guarantees uniform Li plating via boosting interfacial Li⁺ ion transport at the interface. The Li⁺ ion boosting kinetics were deeply analyzed using simulations and spectroscopic analysis. It is revealed that the hydroxyl-functionalized BN can decrease kinetic energy barriers for Li⁺ ions and strongly holds TFSI^- ions, thereby ensuring faster Li⁺ ion migration between electrodes and electrolytes. Tailoring the interfacial Li⁺ ion dynamics with hybrid SEI renders the Li transference number enhancement from 0.391 to 0.562 and 0.178 to 0.327 in liquid and solid-state cells, respectively. Moreover, Li symmetric cells with hybrid SEI exhibit an ultrahigh stability over 3500 h at 2 mA cm^-2 with 2 mA h cm^-2, along with the improved solid-state LMB performances. Our results suggest increasing Li⁺ ion transport at the interface is an alternative to resolve Li anode issues.

FEC Additive for Improved SEI Film and Electrochemical Performance of the Lithium Primary Battery

The solid electrolyte interphase (SEI) film plays a significant role in the capacity and storage performance of lithium primary batteries. The electrolyte additives are essential in controlling the morphology, composition and structure of the SEI film. Herein, fluoroethylene carbonate (FEC) is chosen as the additive, its effects on the lithium primary battery performance are investigated, and the relevant formation mechanism of SEI film is analyzed. By comparing the electrochemical performance of the Li/AlF3 primary batteries and the microstructure of the Li anode surface under different conditions, the evolution model of the SEI film is established. The FEC additive can decrease the electrolyte decomposition and protect the lithium metal anode effectively. When an optimal 5% FEC is added, the discharge specific capacity of the Li/AlF3 primary battery is 212.8 mAh g−1, and the discharge specific capacities are respectively 205.7 and 122.3 mAh g−1 after storage for 7 days at room temperature and 55 °C. Compared to primary electrolytes, the charge transfer resistance of the Li/AlF3 batteries with FEC additive decreases, indicating that FEC is a promising electrolyte additive to effectively improve the SEI film, increase discharge-specific capacities and promote charge transfer of the lithium primary batteries.

A Highly Reversible Lithium Metal Anode by Constructing Lithiophilic Bi-Nanosheets

As a favorable candidate for the next-generation anode materials, metallic lithium is faced with two crucial problems: uncontrollable lithium plating/stripping process and huge volume expansion during cycling. Herein, a 3D lithiophilic skeleton modified with nanoscale Bi sheets (Ni@Bi Foam, i.e., NBF) through one-step facile substitution reaction is constructed. Benefiting from the nanoscale modification, smooth and dense lithiophilic Li₃ Bi layer is in situ formed, which improves the uniform deposition of Li subsequently. Meanwhile, the 3D structure inhibits the growth of Li dendrites effectively by reducing local areal current density. Consequently, the NBF exhibits outstanding cycling stability with a high average Coulombic efficiency of 98.46% at 1 mA cm^-2 with 1 mAh cm^-2 (>500 cycles). Symmetrical cell with NBF exhibits a high reversibility at 1 mA cm^-2 with 1 mAh cm^-2 (>2000 h). Moreover, superior long-term cycling and rate performance of NBF@Li anode are also acquired when assembled with high areal loading of LiFePO₄ (10.1 mg cm^-2 ) cathode (Negative/Positive ratio: 2.91). Even in anode-free metal lithium batteries, NBF has higher capacity during cycling compared with NF. To conclude, NBF shows excellent electrochemical performance and provides an idea of facile preparation method which can be extend to other metal batteries.

Fluorinated Interface Layer with Embedded Zinc Nanoparticles for Stable Lithium-Metal Anodes

Lithium-metal batteries are promising candidates for the next-generation energy storage devices. However, notorious dendrite growth and an unstable interface between Li and electrolytes severely hamper the practical implantation of Li-metal anodes. Here, a robust solid electrolyte interphase (SEI) layer with flexible organic components on the top and plentiful LiF together with lithiophilic Zn nanoparticles on the bottom is constructed on Li metal based on the spray quenching method. The fluorinated interface layer exhibits remarkable stability to shield Li from the aggressive electrolyte and restrain dendrite growth. Accordingly, the modified Li electrode delivers a stable cycling for over 400 cycles at 3 mA cm^-2 in symmetric cells. An improved capacity retention is also achieved in a full cell with a LiFePO₄ cathode. This novel design of the artificial SEI layer offers rational guidance for the further development of high-energy-density lithium-metal batteries.