To overcome the shuttle effect in Li–S batteries, novel biomimetic molecule catalysts are synthesized by grafting hemin molecules to three functionalized carbon nanotube systems (CNTs–COOH, CNTs–OH, and CNTs–NH2). The Li–S battery using the CNTs–COOH@hemin cathode exhibits the optimal initial specific capacity (1637.8 mAh g−1) and cycle durability (up to 1800 cycles). Various in situ characterization techniques, such as Raman spectroscopy, Fourier‐transform infrared reflection absorption spectroscopy, and UV–vis spectroscopy, combined with density functional theory computations are used to investigate the structure–reactivity correlation and the working mechanism in the Li–S system. It is demonstrated that the unique structure of the CNTs‐COOH@hemin composite with good conductivity and adequate active sites resulting from molecule catalyst as well as the strong absorption to polysulfides entrapped by the coordinated Fe(III) complex with FeO bond enables the homogeneous dispersion of S, facilitates the catalysis and conversion of polysulfides, and improves the battery's performance.

Lithium metal anodes demonstrate inferior cycling stability due to uncontrolled Li deposition and large volume fluctuation. Composite Li metal anodes with a 3D host show stable Li deposition. Nevertheless, the advantages of a host are achieved by the joint effect of various parameters. The effect of a single parameter of a host on Li deposition is veiled, hindering the rational design of a host. Herein, a decoupling method is demonstrated to decipher the effect of host electrical conductivity, a vital parameter, on the behaviors of Li deposition. In order to decouple the effect of host electrical conductivity, a conductive host is modulated by in situ formation of a polymer coating while maintaining the other parameters unchanged. The host electrical conductivity dictates the distribution of electric potential in the vicinity of the host, then the transport of Li ions, and finally behaviors of Li deposition. The cycling performance of the host with high electrical conductivity outperforms that with low electrical conductivity. This work initiates a decoupling methodology to probe the effect of host properties on the behaviors of Li deposition, and provides guidance for the rational design of Li metal anode host materials.

A 3D host decorated with lithiophilic sites has emerged as a promising strategy to stabilize lithium metal anode by guiding uniform Li deposition and relieving volume fluctuations. Herein, the evolution process of lithiophilic sites in a 3D host under practical conditions is disclosed in a typical system with metal‐based lithiophilic sites. Lithiophilic sites decreasing nucleation overpotential, however this effect gradually disappears during cycles under practical conditions. The significantly increased cycling capacity under practical conditions results in a rapid accumulation of dead Li compared with mild conditions. The dead Li covers the lithiophilic sites and blocks the diffusion channels of Li ions to the lithiophilic sites, failing to decrease the nucleation overpotentials. Once the dead Li has been removed after long cycles, the lithiophilic sites can still work. This work discloses the failure mechanism of lithiophilic sites and provides a guideline for designing lithiophilic hosts under practical conditions.

The cycling stability of lithium metal batteries is steadily improving. The safety issues, which mainly result from the employment of flammable solvents, should be strongly considered for practical Li metal batteries. Nonflammable solvents can mitigate fire hazards; however, their employment irreversibly deteriorates the cycling stability of working batteries owing to intrinsic high reactivity against Li metal. Herein, regulating solvation structure in a dimethylacetamide (DMAC)‐based electrolyte is proposed to achieve compatibility between cycling stability and nonflammability of electrolytes. DMAC, a nonflammable solvent, is employed to construct a nonflammable localized high‐concentration electrolyte (LHCE). In the DMAC‐based LHCE, there are abundant aggregate clusters resulting in the formation of anion‐derived solid electrolyte interphase to circumvent parasitic reactions between DMAC solvents and Li metal and to improve the uniformity of Li deposition, which ensures the compatibility between cycling stability under practical conditions and nonflammability of electrolytes. This work opens an emerging avenue to construct long‐cycling and safe Li metal batteries by manipulating solvation structure in nonflammable electrolytes.

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Pd/O co-doped MoSx catalyst with an excellent HER performance is designed by an upgraded sacrificial-counter-electrode method. DFT calculations confirm that the Pd/O co-doping and the unsaturated S atoms around the defects (PdMo + OS) would enormously promote the HER activity.

Water splitting is considered to be a very promising alternative to greenly produce hydrogen, and the key to optimizing this process is the development of suitable electrocatalysts. Here, a sacrificial‐counter‐electrode method to synthesize a MoS x /carbon nanotubes/Pt catalyst (0.55 wt% Pt loading) is developed, which exhibits a low overpotential of 25 mV at a current density of 10 mA cm −2 , a low Tafel slope of 27 mV dec −1 , and excellent stability under acidic conditions. The theory calculations and experimental results confirm the high hydrogen evolution activity that is likely due to the fact that the S atoms in MoS x can be substituted with O atoms during a potential cycling process when using Pt as a counter‐electrode, where the O atoms act as bridges between the catalytic PtO x particles and the MoS x support to generate a MoS x –O–PtO x structure, allowing the Pt atoms to donate more electrons thus facilitating the hydrogen evolution reaction process.

Lithium (Li) metal is strongly regarded as a promising anode for next‐generation secondary batteries. However, the nonuniform plating/stripping and volume fluctuation of the Li metal anode give rise to low Coulombic efficiency and short lifespan of Li metal batteries, which hinder practical applications of the Li metal anode. A composite Li metal anode that employs a stable porous host has been proposed as a promising strategy to regulate the behaviors of Li plating/stripping and relieve volume fluctuation. In a porous host, the basic building block is a pore. The pore structure affects the distribution of electric and Li‐ion concentration fields during Li plating/stripping, thus regulating Li plating/stripping and the lifespan of the composite Li metal anode. Therefore, herein, the recent progress in investigating the behavior of Li plating/stripping in a pore based on liquid electrolytes is summarized from the aspects of pore diameter, depth, and tortuosity. Furthermore, the perspectives of rational design of the pore structure for a composite Li metal anode are presented to promote the development of Li metal anodes.