Decorating Phosphorus Anode with SnO2 Nanoparticles To Enhance Polyphosphides Chemisorption for High-Performance Lithium-Ion Batteries

High-performance rechargeable monovalent- and bivalent-ion batteries: from emerging nanomaterials to in-depth mechanisms

Conventional fossil fuels are facing the risk of exhaustion and issues of environmental pollution in many places around the world, making sustainable new energies more important than ever before. Thus, efficient energy-storage systems are receiving broad attention. Among them, research into and application of rechargeable batteries have been quite attractive since the end of the last century. To improve the cycling performance of rechargeable batteries, a great variety of electrode nanomaterials and electrolyte systems have been developed; while enhancement mechanisms are being studied intensively. Here, we provide a comprehensive review of some representative rechargeable monovalent- and bivalent-ion batteries, including lithium-ion batteries (LIBs), sodium-ion batteries (SIBs), lithium-sulfur batteries (LSBs), and bivalent-ion batteries, such as zinc-ion batteries (ZIBs) and magnesium-ion batteries (MIBs). Some hybrid-ion batteries like magnesium/lithium hybrid batteries (MLHBs) and magnesium/sodium hybrid batteries (MNHBs) are also introduced, with a focus on emerging active nanomaterials and deep insights into their enhancement mechanisms. It is expected that the summaries and the proposed outlook presented here will be valuable for a broad range of researchers who are working on energy-storage materials and battery systems.

Mo-O-Sn Bond Boosting Kinetics of MoO2-xSnO2/Sn Anode for High-Performance Li-ion Batteries

Obtaining a robust electrode composed of Sn-based metal oxides and carbonaceous matrix through nanoscale structure engineering is essential for effectively improving Li-ion batteries' electrochemical performance and stability. Herein, we report a bimetallic MoO2-xSnO2/Sn nanoparticles uniformly anchored on N, S co-doped graphene nanosheets (MoO2-xSnO2/Sn@NSG) as an anode electrode for Li-ion battery via a one-step hydrothermal and thermal treatment approach. In the MoO2-xSnO2/Sn nanocomposite, the generated Sn-O-Mo bond can modulate the electronic and composition structures to improve the intrinsic conductivity of SnO2 and reinforce the structural stability during cycles. Moreover, featuring excellent electronic conductivity via coupling of MoO2-xSnO2/Sn and hierarchical NBG matrix, the MoO2-xSnO2/Sn@NSG electrode possesses ultrafast electrochemical kinetics and superior long-term cycling stability and rate capability. Additionally, the hierarchical MoO2-2SnO2/Sn@NSG can suppress the aggregation and accommodate the volume variations of active substances, thereby providing more lithium storage sites. Consequently, the optimized MoO2-2SnO2/Sn@NSG anode exhibits a high reversible capacity of 904 mA h g-1 at 0.2 A g-1 and excellent cycling performance with the reversible capacity of 456 mAh g-1 at 1 A g-1 over 600 cycles. The universal synthesis technology of bimetallic oxide anodes for advanced LIBs may provide vital guidance in designing high-performance energy-storage materials.

Waxberry-like TiO2 with Synergistic Surface Modification of Pyrolytic Carbon Coating and Carbon Nanotubes as an Anode for Li-Ion Battery

Titanium dioxide (TiO2) as an anode material for lithium-ion batteries (LIBs) has the advantages of tiny volume expansion, high operating voltage, and outstanding safety performance. However, due to the low conductivity of TiO2 and the slow diffusion rate of lithium ions (Li+), it is limited in the application of LIBs. Therefore, waxberry-like TiO2 comodified by pyrolytic carbon coating and carbon nanotubes was prepared in this work. The waxberry-like TiO2 with nanorods on its surface shortens the diffusion distance of Li+. Carbon nanotubes and waxberry-like TiO2 are tightly combined through electrostatic assembly and form a cross-linked conductive network to provide more electron transmission paths. A thin layer of pyrolytic carbon wraps carbon nanotubes and waxberry-like TiO2, which enhance the conductivity of the composites and ensure the structural integrity of the materials throughout the cycling process. The experimental data revealed that the discharge-specific capacity of TiO2@CNT@C is 170.5 mAh g-1 after 3000 cycles at a large current density of 5 A g-1, and the discharge-specific capacity is still 143 mAh g-1 at the superhigh rate of 10 A g-1, which provides excellent rate performance and cyclic stability. The efficient dual-carbon modification strategy could potentially be extended to other materials.

LiF-induced in-situ engineering of a dense inorganic SEI for superior lithium storage in black phosphorus anode

Black phosphorus (BP) has been highly regarded as a favourable candidate for fast-charging anode applications owing to its high theoretical capacity and advantageous charge-discharge platform. However, BP faces challenges related to compromised electrochemical performance resulting from an unstable solid-electrolyte interface (SEI) and substantial volumetric expansion. This study proposes the engineering of an inorganic-dense SEI on the surface of BP-C through the strategic incorporation of lithium fluoride (LiF). The presence of LiF in the system preferentially promotes LiPF6 adsorption from the electrolyte, facilitating the in-situ formation of a lithium-enriched inorganic SEI film on the BP-C particulate surfaces. This strategic formation effectively mitigates subsequent electrolytic decomposition, accommodates volumetric expansion, and substantially improves the rate capability and cycling stability of the system. Consequently, the BP-LiF-C electrode demonstrates high initial coulombic efficiency of 86.8 % and maintains a steady capacity of 926.1 mAh g-1 over 700 cycles at 2000 mA g-1. Moreover, when paired with a LiFePO4 cathode, the full cell exhibits long cycling stability, retaining 98.6 % of its capacity after 500 cycles at 2000 mA g-1, and performs at high rate. Therefore, utilising LiF to modulate the interfacial architecture of BP-based electrode composites provide notable guidance to enhance energy storage systems.

Bionic Capsule Lithium-Ion Battery Anodes for Efficiently Inhibiting Volume Expansion

Magnetite (Fe3O4) has a large theoretical reversible capacity and rich Earth abundance, making it a promising anode material for LIBs. However, it suffers from drastic volume changes during the lithiation process, which lead to poor cycle stability and low-rate performance. Hence, there is an urgent need for a solution to address the issue of volume expansion. Taking inspiration from how glycophyte cells mitigate excessive water uptake/loss through their cell wall to preserve the structural integrity of cells, we designed Fe3O4@PMMA multi-core capsules by microemulsion polymerization as a kind of anode materials, also proposed a new evaluation method for real-time repair effect of the battery capacity. The Fe3O4@PMMA anode shows a high reversible specific capacity (858.0 mAh g-1 at 0.1 C after 300 cycles) and an excellent cycle stability (450.99 mAh g-1 at 0.5 C after 450 cycles). Furthermore, the LiNi0.8Co0.1Mn0.1O2/Fe3O4@PMMA pouch cells exhibit a stable capacity (200.6 mAh) and high-capacity retention rate (95.5 %) after 450 cycles at 0.5 C. Compared to the original battery, the capacity repair rate of this battery is as high as 93.4 %. This kind of bionic capsules provide an innovative solution for improving the electrochemical performance of Fe3O4 anodes to promote their industrial applications.

In Situ Construction of Crumpled Ti3C2Tx Nanosheets Confined S-Doping Red Phosphorus by Ti-O-P Bonds for LIBs Anode with Enhanced Electrochemical Performance

Red phosphorus (RP) with a high theoretical specific capacity (2596 mA h g-1) and a moderate lithiation potential (∼0.7 V vs Li+/Li) holds promise as an anode material for lithium-ion batteries (LIBs), which still confronts discernible challenges, including low electrical conductivity, substantial volumetric expansion of 300%, and the shuttle effect induced by soluble lithium polyphosphide (LixPPs). Here, S-NRP@Ti3C2Tx composites were in situ prepared through a phosphorus-amine-based method, wherein S-doped red phosphorus nanoparticles (S-NRP) grew and anchored on the crumpled Ti3C2Tx nanosheets via Ti-O-P bonds, constructing a three-dimensional porous structure which provides fast channels for ion and electron transport and effectively buffers the volume expansion of RP. Interestingly, based on the results of adsorption experiments of polyphosphate and DFT calculation, Ti3C2Tx with abundant oxygen functional groups delivers a strong chemical adsorption effect on LixPPs, thus suppressing the shuttle effect and reducing irreversible capacity loss. Furthermore, S-doping improved the conductivity of red phosphorus nanoparticles, facilitating Li-P redox kinetics. Hence, the S-NRP@Ti3C2Tx anode demonstrates outstanding rate performance (1824 and 1090 mA h g-1 at 0.2 and 4.0 A g-1, respectively) and superior cycling performance (1401 mAh g-1 after 500 cycles at 2.0 A g-1).

Vacancy-Driven High-Performance Metabolic Assay for Diagnosis and Therapeutic Evaluation of Depression

Depression is one of the most common mental illnesses and is a well-known risk factor for suicide, characterized by low overall efficacy (<50%) and high relapse rate (40%). A rapid and objective approach for screening and prognosis of depression is highly desirable but still awaits further development. Herein, a high-performance metabolite-based assay to aid the diagnosis and therapeutic evaluation of depression by developing a vacancy-engineered cobalt oxide (Vo-Co3O4) assisted laser desorption/ionization mass spectrometer platform is presented. The easy-prepared nanoparticles with optimal vacancy achieve a considerable signal enhancement, characterized by favorable charge transfer and increased photothermal conversion. The optimized Vo-Co3O4 allows for a direct and robust record of plasma metabolic fingerprints (PMFs). Through machine learning of PMFs, high-performance depression diagnosis is achieved, with the areas under the curve (AUC) of 0.941-0.980 and an accuracy of over 92%. Furthermore, a simplified diagnostic panel for depression is established, with a desirable AUC value of 0.933. Finally, proline levels are quantified in a follow-up cohort of depressive patients, highlighting the potential of metabolite quantification in the therapeutic evaluation of depression. This work promotes the progression of advanced matrixes and brings insights into the management of depression.

Synthesis of heterointerfaces in NiO/SnO2 coated nitrogen-doped graphene for efficient lithium storage

Currently, it remains a challenge to make comprehensive improvements to overcome the disadvantages of volume expansion, Li2O irreversibility and low conductivity of SnO2. Heterostructure construction has been investigated as an effective strategy to promote electron transfer and surface reaction kinetics, leading to high electrochemical performance. Herein, NiO/SnO2 heterojunction modified nitrogen doped graphene (NiO/SnO2@NG) anode materials were prepared using hydrothermal and carbonization techniques. Based on the excellent structural advantages, sufficiently small NiO/SnO2 heterojunction nanoparticles increase the interfacial density to promote Li2O decomposition, and the built-in electric field accelerates the charge transport rate to improve the conductivity. The three-dimensional porous graphene framework effectively mitigates volume expansion during cycling and stabilizes the reactive interface of electrode materials. The results show that the NiO/SnO2@NG mixture has high reversible specific capacity (938.8 mA h g-1 after 450 cycles at 0.1 A g-1), superior multiplicity performance (374.5 mA h g-1 at 3.0 A g-1) and long cycle life (685.3 mA h g-1 after 1000 cycles at 0.5 A g-1). Thus, this design of introducing NiO to form heterostructures with SnO2 is directly related to enhancing the electrochemical performance of lithium-ion batteries (LIBs).