Current methods for synthesizing nanoscale red phosphorus (NRP), including ball-milling and vaporization–condensation, have various limitations. More effective engineering of the properties of these materials would promote their application in sodium-ion batteries. Herein, we report a simple phosphorus-amine-based method for the scalable preparation of NRP with high yield. We confirm that red phosphorus is highly soluble in ethylenediamine and that addition of H+ precipitates a network of NRP, where the size distribution is controlled by the H+ concentration. Through the use of this method, uniform NRP with particle sizes of 5–10 nm was dispersed in situ on the surfaces of reduced graphene oxide (rGO) with a controllable loading ratio. We attribute the formation of this structure to strong adsorption between the red phosphorus–ethylenediamine complex and rGO. The binding between NRP/Na3P and rGO effectively stabilized the NRP on rGO throughout charging/discharging processes, therefore enabling the NRP–rGO composite to deliver a high capacity of 2057 mA h g–1 at a current density of 100 mA g–1 and excellent long-cycling performance.

Porous activated carbons are considered to be promising CO2 adsorbents due to their high specific surface area, high chemical stability, and tailorable surface properties. However, their low CO2 capture capacity and inferior CO2/N2 selectivity have hindered their application. Here, we describe novel fishnet-like, polybenzoxazine-based porous carbons (PBZCs) prepared by a single-step monomer thermal curing, carbonization, and activation process. The PBZCs exhibit an ultrahigh CO2 uptake capacity of 8.44 mmol g–1 and a superior CO2/N2 IAST selectivity of 56 (at 273 K, 1 bar). Such excellent CO2 adsorption performance may to some extent be ascribed to a high specific surface area and a large ultramicropore volume. However, the results reveal that the CO2 capture capacity is not solely associated with porosity. It may also be attributable to the abundant hydroxyl groups of the PBZCs, which may form hydrogen bonds with CO2 molecules. The role of the oxygen functionalities of porous carbon for CO2 capture was further demonstrated through theoretical calculation combined with experimental analysis. Hydrogen bonding lowers the binding energy between the carbon framework and CO2 molecules, which greatly facilitates CO2 adsorption. Furthermore, the novel fishnet-like structure can anchor CO2 molecules effectively and selectively. These PBZC carbons are potentially promising CO2 adsorbents.

Transition-metal selenides are attractive cathode materials for rechargeable aluminum batteries (RABs) because of their high specific capacity, superior electrical properties, and low cost. To overcome the associated challenges of low structural stability and poor reaction kinetics, a spatial isolation strategy was applied to develop RAB cathodes comprising ultrafine CoSe 2 particles embedded in nitrogen-doped porous carbon nanosheet (NPCS)/MXene hybrid materials; the two-dimensional NPCS structures were derived from the self-assembly of metal frameworks on MXene surfaces. This synthetic strategy enabled control over the particle size of the active materials, even at high pyrolysis temperature, thereby allowing investigations into the effect of size on the electrochemical behavior. Spectroscopic analysis revealed that the CoSe 2 -NPCS electrode exhibited a high discharge capacity (436 mAh g −1 at 1 A g −1 ), excellent rate capability (122 mA h g −1 at 5 A g −1 ), and long-term cycling stability (212 mAh g −1 after 500 cycles at 1 A g −1 ). Theoretical calculations regarding the Co adsorption affinities at various N-doping sites elucidated the synergistic effects of N−C/MXene hybrids for boosting the reaction kinetics and Co adsorption behavior in this system. This work offers an effective material engineering approach for designing electrodes with high rate stability for high-energy RABs.

The practical application of Li‐metal anode in high‐energy rechargeable Li batteries is still hindered by the uncontrollable formation of Li dendrites. Here, a facile way is reported to stabilize Li‐metal anode by building dendrite‐like Li3Mg7 alloys enriched with Li‐containing polymers as the physical protecting layer and LiH as the Li‐ion conductor. This unique dendritic structure effectively reduces local current density and accommodates volume change during the repeated Li plating/stripping process. More importantly, lithiophilic Li3Mg7 alloys not only guide the uniform Li deposition down into the below Li metal upon Li deposition, but also thermodynamically promote the extraction of Li during the reverse Li stripping process, which suppresses the parasitic reactions occurring on the surface of Li metal and hence inhibits the formation of Li dendrites. Moreover, the facile diffusion of Mg from Li3Mg7 alloys toward Li metal below is thermodynamically permitted, which leads to a uniform distribution of LiMg alloys inside the whole electrode and thus benefits long‐term deep cycling stability. As a result, the protected Li‐metal anode delivers stable and dendrite‐free cycling performance at 10 mA h cm−2 for over 900 h. When coupling this anode with LiFePO4 and S cathodes, the thus‐assembled full cells exhibit superior cycling stability.

Red phosphorus (RP) has attracted great attention as a potential candidate for anode materials of high-energy density sodium-ion batteries (NIBs) due to its high theoretical capacity, appropriate working voltage, and natural abundance. However, the low electrical conductance and huge volumetric variation during the sodiation–desodiation process, causing poor rate performance and cyclability, have limited the practical application of RP in NIBs. Herein, we report a rational strategy to resolve these issues by encapsulating nanoscaled RP into conductive and networked carbon nanocages (denoted as RP@CNCs) using a combination of a phosphorus-amine based method and evacuation-filling process. The large interior cavities volume of CNCs and controllable solution-based method enable the ultrahigh RP loading amount (85.3 wt %) in the RP@CNC composite. Benefiting from the synergic effects of the interior cavities and conductive network, which afford high structure stability and rapid electron transport, the RP@CNC composite presents a high systematic capacity of 1363 mA h g–1 at a current density of 100 mA g–1 after 150 cycles, favorable high-rate capability, and splendid long-cycling performance with capacity retention over 80% after 1300 cycles at 5000 mA g–1. This prototypical design promises an efficient solution to maximize RP loading as well as to boost the electrochemical performance of RP-based anodes.