Silicon is a low price and high capacity anode material for lithium-ion batteries. The yolk-shell structure can effectively accommodate Si expansion to improve stability. However, the limited rate performance of Si anodes can’t meet people’s growing demand for high power density. Herein, the phosphorus-doped yolk-shell Si@C materials (P-doped Si@C) were prepared through carbon coating on P-doped Si/SiOx matrix to obtain high power and stable devices. Therefore, the as-prepared P-doped Si@C electrodes delivered a rapid increase in Coulombic efficiency from 74.4% to 99.6% after only 6 cycles, high capacity retention of ∼ 95% over 800 cycles at 4 A·g−1, and great rate capability (510 mAh·g−1 at 35 A·g−1). As a result, P-doped Si@C anodes paired with commercial activated carbon and LiFePO4 cathode to assemble lithium-ion capacitor (high power density of ∼ 61,080 W·kg−1 at 20 A·g−1) and lithium-ion full cell (good rate performance with 68.3 mAh·g−1 at 5 C), respectively. This work can provide an effective way to further improve power density and stability for energy storage devices.

With a theoretical capacity of 847 mAh g À 1 , Sn has emerged as promising anode material for sodium-ion batteries (SIBs). However, enormous volume expansion and agglomeration of nano Sn lead to low Coulombic efficiency and poor cycling stability. Herein, an intermetallic FeSn 2 layer is designed via thermal reduction of polymer-Fe 2 O 3 coated hollow SnO 2 spheres to construct a yolk-shell structured Sn/FeSn 2 @C. The FeSn 2 layer can relieve internal stress, avoid the agglomeration of Sn to accelerate the Na + transport, and enable fast electronic conduction, which endows quick electrochemical dynamics and long-term stability. As a result, the Sn/FeSn 2 @C anode exhibits high initial Coulombic efficiency (ICE = 93.8 %) and a high reversible capacity of 409 mAh g À 1 at 1 A g À 1 after 1500 cycles, corresponding to an 80 % capacity retention. In addition, NVP//Sn/FeSn 2 @C sodium-ion full cell shows outstanding cycle stability (capacity retaining rate of 89.7 % after 200 cycles at 1 C).

The NaTi2(PO4)3 (NTP) anode materials exhibit high Na+ diffusion dynamics; carbon-based materials can effectively improve its limited electronic conductivity. However, the low Na+ diffusion of NTP/C composite materials from inhomogeneous carbon mixing or uncontrollable carbon coating cannot keep up with fast electron transfer, leading to undesirable electrochemical performances. Herein, a uniform and controllable carbon layer is designed on the self-supported-coated NTP nanorod arrays with binder-free (NTP@C NR) to improve Na+ and electron kinetics simultaneously. As a result, the NTP@C NR electrodes possess initial coulombic efficiency (ICE = 97%), good rate capabilities (89.1 mA h g–1 at 100 C), and stability with ≈78.4% of capacity retention rate at even 30 C over 1200 cycles. The sodium-ion capacitors with NTP@C NR as an anode and commercially activated carbon as a cathode exhibit ∼9180.0 W kg–1 of power density at 10 A g–1 and super high retention of ≈94.5% at 1 A g–1 over 7000 cycles. This work will help balance transport kinetics between the ion and electron for materials applied in storage devices.

The electrocatalytic reduction of nitrobenzene to aniline normally faces high overpotential and poor selectivity because of its six-electron redox nature. Herein, a Ag nanoparticles/laser-induced-graphene (LIG) heterointerface was fabricated on polyimide films and employed as an electrode material for an efficient nitrobenzene reduction reaction (NBRR) via a onestep laser direct writing technology. The first-principles calculations reveal that Ag/LIG shows the lowest activation barriers for the NBRR, which could be attributed to the optimum adsorption of the H atom realized by the appropriate interaction between Ag/ LIG heterointerfaces and nitrobenzene. As a result, the overpotential of the NBRR is reduced by 217 mV after silver loading, and Ag/LIG shows a high aniline selectivity of 93%. Furthermore, an electrochemical reduction of nitrobenzene in tandem with an electrochemical oxidative polymerization of aniline was designed to serve as an alternative method to remove nitrobenzene from the aqueous solution. This strategy highlights the significance of heterointerfaces for efficient electrocatalysts, which may stimulate the development of novel electrocatalysts to boost the electrocatalytic activity.

Lithium−sulfur (Li−S) batteries, as a prospective energy storage system, are still plagued by many problems that prevent them from their application, especially the low content of sulfur in the cathode. Herein, a cathode material with S up to 93 wt % is designed via a hollow donor−π−acceptor heterosystem, which combines catalytic sites, adsorption sites, and good conductivity together. Following this guidance, a hollow porous carbon sphere is prepared with CoO particles and single V atoms decorated on it (Co/V-HPCS), providing ultrahigh volumetric space for sulfur. Even the electrode made of sulfur-loaded Co/V-HPCS (Co/V-HPCS@S) has a high content of 90 wt % (sulfur content in the electrode is ∼83.5 wt %), and the cathode exhibits an excellent discharge capacity of 575.2 mAh g −1 under 0.2C after 100 cycles. With careful analysis by means of a high-resolution transmission electron microscope (HRTEM), the catalytic amounts of CoO particles and single V atoms loaded on the carbon shell are confirmed, which endows the material with outstanding catalytic ability to transfer sulfur and excellent adsorption of polysulfides. This concept of the cathode material increases the possibility of advanced long-life Li−S batteries with high tap density and high energy density.