Phosphorus and tin phosphide based materials that are extensively researched as the anode for Na-ion batteries mostly involve complexly synthesized and sophisticated nanocomposites limiting their commercial viability. This work reports a Sn₄P₃-P (Sn:P = 1:3) at graphene nanocomposite synthesized with a novel and facile mechanochemical method, which exhibits unrivalled high-rate capacity retentions of >550 and 371 mA h g^-1 at 1 and 2 A g^-1, respectively, over 1000 cycles and achieves excellent rate capability (>815, ≈585 and ≈315 mA h g^-1 at 0.1, 2, and 10 A g^-1, respectively).

Nanostructured silicon has been intensively investigated as a high capacity Li-ion battery anode. However, the commercial introduction still requires advances in the scalable synthesis of sophisticated Si nanomaterials and electrodes. Moreover, the electrode degradation due to volume changes upon de-/lithiation, low areal electrode capacity, and application of large amounts of advanced conductive additives are some of the challenging aspects. Here we report a Si electrode, prepared from direct deposition of Si nanoparticles on a current collector without any binder or conducting additives, that addresses all of the above issues. It exhibits an excellent cycling stability and a high capacity retention taking advantages of what appears to be a locally protective, yolk-shell reminiscent, solid electrolyte interphase (SEI) formation. Cycling an electrode with a Si nanoparticle loading of 2.2 mg cm⁻² achieved an unrivalled areal capacity retention, specifically, up to 4.2 mAh cm⁻² and ~ 1.5 mAh cm⁻² at 0.8 mA cm⁻² and 1.6 mA cm⁻², respectively.

Black phosphorus (BP) has received increasing research attention as an anode material in sodium-ion batteries (SIBs), owing to its high capacity, electronic conductivity, and chemical stability. However, it is still challenging for BP-based SIB anodes to achieve a high electrochemical performance utilizing cost-effective materials and synthetic methods. This work presents a sodium-ion anode based on a BP-carbon nanocomposite synthesized from commercial red phosphorus and low-cost super P carbon black. Intimate interactions between BP and carbon are present, which helps to maintain the electrical conduction during cycling and, therefore, a high cycling stability is achieved. It exhibits a high capacity retention of 1381mAhg^-1 for sodium-ion storage after 100 cycles, maintaining 90.5% of the initial reversible capacity. Such high performance/materials cost ratio may provide direction for future phosphorus-based anodes in high energy density SIBs.

Super P carbon black (SPCB) has been widely used as a conducting additive in Li/Na ion batteries to improve the electronic conductivity. However, there has not yet been a comprehensive study on its structure and electrochemical properties for Li/Na ion uptake, though it is important to characterize its contribution in any study of active materials that uses this additive in non-negligible amounts. In this article the structure of SPCB has been characterized and a comprehensive study on the electrochemical Li/Na ion uptake capability and reaction mechanisms are reported. SPCB exhibits a considerable lithiation capacity (up to 310 mAh g^–1) from the Li ion intercalation in the graphite structure. Sodiation in SPCB undergoes two stages: Na ion intercalation into the layers between the graphene sheets and the Na plating in the pores between the nano-graphitic domains, and a sodiation capacity up to 145 mAh g^–1 has been achieved. Moreover, the influence of the type and content of binders on the lithiation and sodiation properties has been investigated. The cycling stability is much enhanced with sodium carboxymethyl cellulose (NaCMC) binder in the electrode and fluoroethylene carbonate (FEC) in the electrolyte; and a higher content of binder improves the Coulombic efficiency during dis-/charge.

Si-based anode materials in Li-ion batteries (LIBs) suffer from severe volume expansion/contraction during repetitive discharge/charge, which results in the pulverization of active materials, continuous growth of solid electrolyte interface (SE!) layers, loss of electrical conduction, and, eventually, battery failure. Herein, we present unprecedented low-content phosphorene (single-layer black phosphorus) encapsulation of silicon particles as an effective method for improving the electrochemical performance of Si-based LIB anodes. The incorporation of low phosphorene amounts (1%, mass fraction) into Si anodes effectively suppresses the detrimental effects of volume expansion and SE! growth, preserving the structural integrity of the electrode during cycling and achieving enhanced Coulombic efficiency, capacity retention, and cycling stability for Li-ion storage. Thus, the developed method can also be applied to other battery materials with high energy density exhibiting substantial volume changes.