Fatigue-Resistant Interfacial Layer for Safe Lithium Metal Batteries.

The plating/stripping of Li dendrites can fracture the static solid electrolyte interphase (SEI) and cause significant dynamic volume variations in the Li anode, which give rise to poor cyclability and severe safety hazards. Herein, a tough polymer with a slide-ring structure was designed as a self-adaptive interfacial layer for Li anodes. The slide-ring polymer with a dynamically crosslinked network moves freely while maintaining its toughness and fracture resistance, which allows it can to dissipate the tension induced by Li dendrites on the interphase layer. Moreover, the slide-ring polymer is highly stretchable, elastic, and displays an ultrafast self-healing ability, which allows even pulverized Li to remain coalesced without disintegrating upon consecutive cycling. The Li anodes demonstrate greatly improved suppression of Li dendrite formation, as evidenced by the high critical current density (6 mA cm-2 ) and stable cycling for the full cells with high-areal capacity LiFePO4 , high-voltage NCM, and S cathodes.

Toward Practical High-Energy and High-Power Lithium Battery Anodes: Present and Future.

Lithium batteries are key components of portable devices and electric vehicles due to their high energy density and long cycle life. To meet the increasing requirements of electric devices, however, energy density of Li batteries needs to be further improved. Anode materials, as a key component of the Li batteries, have a remarkable effect on the increase of the overall energy density. At present, various anode materials including Li anodes, high-capacity alloy-type anode materials, phosphorus-based anodes, and silicon anodes have shown great potential for Li batteries. Composite-structure anode materials will be further developed to cater to the growing demands for electrochemical storage devices with high-energy-density and high-power-density. In this review, the latest progress in the development of high-energy Li batteries focusing on high-energy-capacity anode materials has been summarized in detail. In addition, the challenges for the rational design of current Li battery anodes and the future trends are also presented.

Limited Lithium Loading Promises Improved Lithium-Metal Anodes in Interface-Modified 3D Matrixes.

Confining Li metal in a three-dimensional (3D) matrix has been proven effective in improving the Li-metal anodes; however, in most studies, the loading of Li in the 3D matrix is far excessive, resulting in a dense bulk Li-metal anode with a low Li-utilization rate, forfeiting the effect of the 3D matrix. Here, we show that limiting the loading of Li metal within an interface-modified 3D carbon matrix not only increases the Li-utilization rate but also improves the electrochemical performance of the Li-metal anode. We use lithiophilic Fe2O3 granules anchored on a 3D carbon fiber scaffold to guide molten Li dispersion onto the fibers with controlled Li loading. Limiting Li loading maximizes the interface lithiophilic effect of the Fe2O3 granules while preserving sufficient space for electrolyte infusion, collectively ensuring uniform Li deposition and fast Li+ transport kinetics. The Li anode with limited Li dosage achieves remarkably improved Li-anode performances, including long lifespan, low voltage polarization, and low electrochemical resistance in both the symmetric cells and full cells. The improved electrochemical performance of the limited Li anode substantiates the importance to reduce Li loading from a fresh perspective and provides an avenue for building practical Li-metal batteries.

Confined Red Phosphorus in Edible Fungus Slag-Derived Porous Carbon as an Improved Anode Material in Sodium-Ion Batteries.

Red phosphorus (RP) as the anode material for the sodium-ion battery (SIB) possesses a high energy density, but the poor electronic conductivity and huge volume change during Na+ insertion/extraction restrict its application. In this work, the edible fungus slag-derived porous carbon (PC) is adopted as a carbon matrix to combine with RP to form PC@RP composites through a facile vaporization-condensation approach. The conductive porous carbon architecture improves the transfer of electron and Na+ in the composite. The robust carbon framework together with the chemical bonding between PC and RP effectively buffer the huge volumetric change of RP. As a result, the PC@RP composite material delivers a specific capacity of 655.1 mA h g-1 at 0.1 A g-1 with a capacity retention of 87% after 100 charging/discharging cycles. In particular, the full SIB assembled with P2-Na2/3Ni1/3Mn1/3Ti1/3O2 as the cathode material and PC@RP as the anode material exhibits a specific capacity of 77.3 mA h g-1 (based on the mass of cathode material) at 0.5 C, and 85% capacity is retained after 100 charging/discharging cycles.

Edible fungus slag derived nitrogen-doped hierarchical porous carbon as a high-performance adsorbent for rapid removal of organic pollutants from water.

In this work, agricultural waste edible fungus slag derived nitrogen-doped hierarchical porous carbon (EFS-NPC) was prepared by a simple carbonization and activation process. Owing to the biodegradation and infiltrability of hyphae, this EFS-NPC possessed an ultra-high specific surface area (3342 m2/g), large pore volume (1.84 cm3/g) and abundant micropores and mesopores. The obtained EFS-NPC could effectively adsorb bisphenol A (BPA) with the maximal adsorption capacity of 1249 mg/g and the removal process reached 89.9% of the equilibrium uptake in the first 0.5 h. Besides, the EFS-NPC showed much better removal performance towards 2,4-dichlorophenol (2,4-DCP) and methylene blue (MB) than commercial activated carbons (Norit RO 0.8 and DARCO granular activated carbon). Furthermore, adsorption isotherms, thermodynamics and kinetics researches indicated that the adsorption process of BPA was monolayer, exothermic and spontaneous. This research has given evidence that the low-cost EFS-NPC can serve as a high-efficient adsorbent for removing organic contaminants from water.

Benzoxazine monomer derived carbon dots as a broad-spectrum agent to block viral infectivity.

Multiple viruses can cause infection and death of millions annually. Of these, flaviviruses are found to be highly prevalent in recent years with no distinctive antiviral therapies. Therefore, there is a desperate need for broad-spectrum antiviral drugs that can be active against a large number of existing and emerging viruses. Herein, we prepared a kind of benzoxazine monomer derived carbon dots (BZM-CDs) and demonstrated their infection-blocking ability against life-threatening flaviviruses (Japanese encephalitis, Zika, and dengue viruses) and non-enveloped viruses (porcine parvovirus and adenovirus-associated virus). It was found that BZM-CDs could directly bind to the surface of the virion, and eventually the first step of virus-cell interaction was impeded. The developed nanoparticles are active against both flaviviruses and non-enveloped viruses in vitro. Thus, the application of BZM-CDs may constitute an intriguing broad-spectrum approach to rein in viral infections.

Basophilic green fluorescent carbon nanoparticles derived from benzoxazine for the detection of Cr(vi) in a strongly alkaline environment.

Fluorescent probes for heavy or transition metal ions in extreme environments are crucially important for practical use. In this work, basophilic green fluorescent carbon nanoparticles (G-CNPs) were synthesized by one-pot hydrothermal treatment of benzoxazine in NaOH aqueous solution. These G-CNPs showed favorable dispersibility in strongly alkaline conditions due to the abundant functional groups on their surface. Based on their good photoluminescence properties and excellent stability, the G-CNPs could be used to detect Cr(vi) in a strongly alkaline environment (pH = 14) through a fluorescence quenching effect. This detection process was achieved selectively among 17 anions within 30 seconds and the limitation was 0.58 µM (S/N = 3). It was revealed that the fluorescence turn-off process was caused by the inner filter effect (IFE) of Cr(vi). This study developed efficient fluorescence sensors based on fluorescent carbon nanoparticles, which could be used in strongly alkaline environments.

Co Nanoparticles/Co, N, S Tri-doped Graphene Templated from In-Situ-Formed Co, S Co-doped g-C3N4 as an Active Bifunctional Electrocatalyst for Overall Water Splitting.

The development of high-performance electrocatalyst with earth-abundant elements for water-splitting is a key factor to improve its cost efficiency. Herein, a noble metal-free bifunctional electrocatalyst was synthesized by a facile pyrolysis method using sucrose, urea, Co(NO3)2 and sulfur powder as raw materials. During the fabrication process, Co, S co-doped graphitic carbon nitride (g-C3N4) was first produced, and then this in-situ-formed template further induced the generation of a Co, N, S tri-doped graphene coupled with Co nanoparticles (NPs) in the following pyrolysis process. The effect of pyrolysis temperature (700, 800, and 900 °C) on the physical properties and electrochemical performances of the final product was studied. Thanks to the increased number of graphene layer encapsulated Co NPs, higher graphitization degree of carbon matrix and the existence of hierarchical macro/meso pores, the composite electrocatalyst prepared under 900 °C presented the best activity for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) with outstanding long-term durability. This work presented a facile method for the fabrication of non-noble-metal-based carbon composite from in-situ-formed template and also demonstrated a potential bifunctional electrocatalyst for the future investigation and application.