Lithium metal is a compelling choice as an anode material for high-energy-density batteries, attributed to its elevated theoretical specific energy and low redox potential. Nevertheless, challenges arise due to its susceptibility to high-volume changes and the tendency for dendritic development during cycling, leading to restricted cycle life and diminished Coulombic efficiency (CE). Here, we innovatively engineered a kind of porous biocarbon to serve as the framework for a lithium metal anode, which boasts a heightened specific surface area and uniformly dispersed ZnO active sites, directly derived from metasequoia cambium. The porous structure efficiently mitigates local current density and alleviates the volume expansion of lithium. Also, incorporating the ZnO lithiophilic site notably reduces the nucleation overpotential to a mere 16 mV, facilitating the deposition of lithium in a compact form. As a result, this innovative material ensures an impressive CE of 98.5% for lithium plating/stripping over 500 cycles, a remarkable cycle life exceeding 1200 h in a Li symmetrical cell, and more than 82% capacity retention ratio after an astonishing 690 cycles in full cells. In all, such a rationally designed Li composite anode effectively mitigates volume change, enhances lithophilicity, and reduces local current density, thereby inhibiting dendrite formation. The preparation of a high-performance lithium anode frame proves the feasibility of using biocarbon in a lithium anode frame.

Layered manganese dioxide (δ-MnO₂) is a promising cathode material for aqueous zinc-ion batteries (AZIBs) due to its high theoretical capacity, high operating voltage, and low cost. However, its practical application faces challenges, such as low electronic conductivity, sluggish diffusion kinetics, and severe dissolution of Mn²⁺. In this study, we developed a δ-MnO₂ coated with a 2-methylimidazole (δ-MnO₂@2-ML) hybrid cathode. Density functional theory (DFT) calculations indicate that 2-ML can be integrated into δ-MnO₂ through both pre-intercalation and surface coating, with thermodynamically favorable outcomes. This modification expands the interlayer spacing of δ-MnO₂ and generates Mn–N bonds on the surface, enhancing Zn²⁺ accommodation and diffusion kinetics as well as stabilizing surface Mn sites. The experimentally prepared δ-MnO₂@2-ML cathode, as predicted by DFT, features both 2-ML pre-intercalation and surface coating, providing more zinc-ion insertion sites and improved structural stability. Furthermore, X-ray diffraction shows the expanded interlayer spacing, which effectively buffers local electrostatic interactions, leading to an enhanced Zn²⁺ diffusion rate. Consequently, the optimized cathode (δ-MnO₂@2-ML) presents improved electrochemical performance and stability, and the fabricated AZIBs exhibit a high specific capacity (309.5 mAh/g at 0.1 A/g), superior multiplicative performance (137.6 mAh/g at 1 A/g), and impressive capacity retention (80% after 1350 cycles at 1 A/g). These results surpass the performance of most manganese-based and vanadium-based cathode materials reported to date. This dual-modulation strategy, combining interlayer engineering and interface optimization, offers a straightforward and scalable approach, potentially advancing the commercial viability of low-cost, high-performance AZIBs.

Silicon–air (Si–air) batteries have received significant attention owing to their high theoretical energy density and safety profile. However, the actual energy density of the Si–air battery remains significantly lower than the theoretical value, primarily due to corrosion issues and passivation. This study used various metal–organic framework (MOF) materials, such as MIL-53(Al), MIL-88(Fe), and MIL-101(Cr), to modify Si anodes. The MOFs were fabricated to have different morphologies, particle sizes, and pore sizes by altering their central metal nodes and ligands. This approach aimed to modulate the adsorption behavior of H₂O, SiO₂, and OH⁻, thereby mitigating corrosion and passivation reactions. Under a constant current of 150 μA, Si–air batteries with MIL-53(Al)@Si, MIL-88(Fe)@Si, and MIL-101(Cr)@Si as anodes demonstrated lifetimes of 293, 412, and 336 h, respectively, surpassing the 276 h observed with pristine silicon anodes. Among these composite anodes, MIL-88(Fe)@Si displayed the best performance due to its superior hydrophobicity and optimal pore size, which enhance OH⁻ migration. This study offers a promising strategy for enhancing Si–air battery performance by developing an anodic protective layer with selective screening properties.

Demand for fast-charging lithium-ion batteries (LIBs) has escalated incredibly in the past few years. A conventional method to improve the performance is to chemically partly substitute the transition metal with another to increase its conductivity. In this study, we have chosen to investigate the lithium diffusion in doped anatase (TiO₂) anodes for high-rate LIBs. Substitutional doping of TiO₂ with the pentavalent Nb has previously been shown to increase the high-rate performances of this anode material dramatically. Despite the conventional belief, we explicitly show that Nb is mobile and diffusing at room temperature, and different diffusion mechanisms are discussed. Diffusing Nb in TiO₂ has staggering implications concerning most chemically substituted LIBs and their performance. While the only mobile ion is typically asserted to be Li, this study clearly shows that the transition metals are also diffusing, together with the Li. This implies that a method that can hinder the diffusion of transition metals will increase the performance of our current LIBs even further.

Developing electrocatalysts to inhibit polysulfide shuttling and expedite sulfur species conversion is vital for the evolution of Lithium-sulfur (Li-S) batteries. This work provides a facile strategy to design an intimate heterostructure of MIL-88A@CdS as a sulfur electrocatalyst combining high sulfur adsorption and accelerated polysulfide conversion. The MIL-88A can give a region of high-ordered polysulfide adsorption, whereas the CdS is an effective nanoreactor for the sulfur reduction reaction (SRR). Notedly, the significant size difference between MIL-88A and CdS enables the unique heterostructure interactions. The large-size MIL-88A ensures a uniform distribution of CdS nanoparticles as a substrate. This configuration facilitates control of the initial polysulfide adsorption position relative to its final deposition site as lithium sulfide. The heterostructure also demonstrates rapid transport and efficient conversion of lithium polysulfides. Consequently, the Li-S battery with MIL-88A@CdS heterostructure modified separator delivers exceptional performance, achieving an areal capacity exceeding 6 mAh cm⁻², an excellent rate capability of 980 mAh g⁻¹ at 5 C, and notable cycling stability in a 2 Ah pouch cell over 100 cycles. This work is significant for elucidating the relationship between heterostructure and electrocatalytic performance, providing great insights for material design aimed at highly efficient future electrocatalysts in practical applications.

The efficient and stable operation of proton exchange membrane fuel cells (PEMFCs) in practical applications can be adversely affected by various contaminants. This study delves into the impact of Cr₂(SO₄)₃ contamination on the gas diffusion layer (GDL) and PEMFC performance, systematically analyzing the physicochemical property changes and their correlation with electrochemical performance. The results indicate that after post-treatment, the GDL surface exhibited exposed carbon fibers, cracks, and large pores in the microporous layer (MPL), with a noticeable detachment of PTFE. There was a marked reduction in C and F element signals, an increase in O element signals, deposition of Cr₂(SO₄)₃, formation of C=O and C=C bonds, appearance of Cr₂(SO₄)₃ characteristic peaks, and changes in pore structure—all suggesting significant alterations in the GDL's surface morphology, structure, and chemical composition. The decline in mechanical strength and thermal stability, and increased surface roughness and resistance negatively impacted fuel cell performance. At high current densities, the emergence of water flooding increased mass transfer resistance from 0.1 Ω cm² to 1.968 Ω cm², with a maximum power density decay rate reaching 71.17%. This study reveals the significant negative impact of Cr₂(SO₄)₃ contamination on GDL and fuel cell performance, highlighting that changes in surface structure, reduced hydrophobicity, and increased mass transfer resistance are primary causes of performance degradation. The findings provide crucial insights for improving GDL materials, optimizing fuel cell manufacturing and operation processes, and addressing contamination issues in practical applications.

Hydrogen peroxide (H₂O₂) is an eco-friendly chemical with widespread industrial applications. However, the commercial anthraquinone process for H₂O₂ production is energy-intensive and environmentally harmful, highlighting the need for more sustainable alternatives. The electrochemical production of H₂O₂ via the two-electron water oxidation reaction (2e⁻ WOR) presents a promising route but is often hindered by low efficiency and selectivity, due to the competition with the oxygen evolution reaction. In this study, we employed high-throughput computational screening and microkinetic modeling to design a series of efficient 2e⁻ WOR electrocatalysts from a library of 240 single-metal-embedded nitrogen heterocycle aromatic molecules (M-NHAMs). These catalysts, primarily comprising post-transition metals, such as Cu, Ni, Zn, and Pd, exhibit high activity for H₂O₂ conversion with a limiting potential approaching the optimal value of 1.76 V. Additionally, they exhibit excellent selectivity, with Faradaic efficiencies exceeding 80% at overpotentials below 300 mV. Structure-performance analysis reveals that the d-band center and magnetic moment of the metal center correlated strongly with the oxygen adsorption free energy ((ΔG_O*), suggesting these parameters as key catalytic descriptors for efficient screening and performance optimization. This study contributes to the rational design of highly efficient and selective electrocatalysts for electrochemical production of H₂O₂, offering a sustainable solution for green energy and industrial applications.

Lithium-sulfur (Li-S) batteries are promising for high-energy-density storage, but their performance is limited by sluggish lithium polysulfide (LiPS) conversion kinetics. Here, we tackle this issue by synthesizing ultrafine truncated octahedral TiO₂ nanocrystals (P-O_v-TiO₂), featuring specific {101} facets and dual defects—phosphorus doping and oxygen vacancies. Acting as an efficient electrocatalyst in the separator, P-O_v-TiO₂ exhibits superior catalytic properties, where oxygen vacancies modulate the electronic structure, enhancing electron enrichment and charge transfer; phosphorus doping tailors the d-band center of the catalyst, strengthening Ti-S interactions between the {101} facets and LiPSs. As a result, Li-S coin cells modified with P-O_v-TiO₂ achieve a high specific capacity of 895 mAh g⁻¹ at 5 C and exhibit a minimal decay rate of 0.14% per cycle over 200 cycles. Furthermore, Li-S pouch cells deliver a high capacity of 1004 mAh g⁻¹ at 0.1 C under lean electrolyte conditions. This study elucidates the mechanisms of charge states on specific crystal planes and deepens our understanding of dual-defect engineering in Li-S electrochemistry, offering a promising approach for developing efficient and cost-effective catalysts for Li-S battery applications.

All-solid-state batteries (ASSBs) are a promising next-generation energy storage solution due to their high energy density and enhanced safety. To achieve this, specialized electrode designs are required to efficiently enhance interparticle lithium-ion transport between solid components. In particular, for active materials with high specific capacity, such as silicon, their volume expansion and shrinkage must be carefully controlled to maintain mechanical interface stability, which is crucial for effective lithium-ion transport in ASSBs. Herein, we propose a mechanical stress-tolerant all-solid-state graphite/silicon electrode design to ensure stable lithium-ion diffusion at the interface through morphology control of active material particles. Plate-type graphite with a high surface-area-to-volume ratio is used to maximize the dispersion of silicon within the electrode. The carefully designed electrode can accommodate the volume changes of silicon, ensuring stable capacity retention over cycles. Additionally, spherical graphite is shown to contribute to improved rate performance by providing an efficient lithium-ion diffusion pathway within the electrode. Therefore, the synergistic effect of our electrode structure offers balanced electrochemical performance, providing practical insights into the mechano–electrochemical interactions essential for designing high-performance all-solid-state electrodes.

All-solid-state batteries (ASSBs) have garnered significant interest as the next-generation in battery technology, praised for their superior safety and high energy density. However, a conductive agent accelerates the undesirable side reactions of sulfide-based solid electrolytes, resulting in poor electrochemical properties with increased interfacial resistance. Here, we propose a wet chemical method rationally designed to achieve a conformal coating of lithium–indium chloride (Li₃InCl₆) onto vapor-grown carbon fibers (VGCFs) as conductive agents. First, with the advantage of the Li₃InCl₆ protective layer, use of VGCF@Li₃InCl₆ leads to enhanced interfacial stability and improved electrochemical properties, including stable cycle performance. These results indicate that the Li₃InCl₆ protective layer suppresses the unwanted reaction between Li₆PS₅Cl and VGCF. Second, VGCF@Li₃InCl₆ effectively promotes polytetrafluoroethylene fibrillization, leading to a homogeneous electrode microstructure. The uniform distribution of the cathode active material in the electrode results in reduced charge-transfer resistance and enhanced Li-ion kinetics. As a result, a full cell with the LiNi_xMn_yCo_zO₂/VGCF@Li₃InCl₆ electrode shows an areal capacity of 7.7 mAh cm⁻² at 0.05 C and long-term cycle stability of 77.9% over 400 cycles at 0.2 C. This study offers a strategy for utilizing stable carbon-based conductive agents in sulfide-based ASSBs to enhance their electrochemical performance.

Photoelectrochemical (PEC) water splitting holds significant promise for sustainable energy harvesting that enables efficient conversion of solar energy into green hydrogen. Nevertheless, achievement of high performance is often limited by charge carrier recombination, resulting in unsatisfactory saturation current densities. To address this challenge, we present a novel strategy for achieving ultrahigh current density by incorporating a bridge layer between the Si substrate and the NiOOH cocatalyst in this paper. The optimal photoanode (TCO/n–p–Si/TCO/Ni) shows a remarkably low onset potential of 0.92 V vs. a reversible hydrogen electrode and a high saturation current density of 39.6 mA·cm⁻², which is about 92.7% of the theoretical maximum (42.7 mA·cm⁻²). In addition, the photoanode demonstrates stable operation for 60 h. Our systematic characterizations and calculations demonstrate that the bridge layer facilitates charge transfer, enhances catalytic performance, and provides corrosion protection to the underlying substrate. Notably, the integration of this photoanode into a PEC device for overall water splitting leads to a reduction of the onset potential. These findings provide a viable pathway for fabricating high-performance industrial photoelectrodes by integrating a substrate and a cocatalyst via a transparent and conductive bridge layer.

Lead (Pb)–zinc (Zn) slags contain large amounts of Pb, causing irreversible damage to the environment. Therefore, developing an effective strategy to extract Pb from Pb–Zn slags and convert them into a renewable high-value catalyst not only solves the energy crisis but also reduces environmental pollution. Herein, we present a viable strategy to recycle Pb and iron (Fe) from Pb–Zn slags for the fabrication of efficient methylammonium lead tri-iodide (r-MAPbI₃) piezocatalysts with single-atom Fe–N₄ sites. Intriguingly, atomically dispersed Fe sites from Pb–Zn slags, which coordinated with N in the neighboring four CH₃NH₃ to form the FeN₄ configuration, were detected in the as-obtained r-MAPbI₃ by synchrotron X-ray absorption spectroscopy. The introduction of Fe single atoms amplified the polarization of MAPbI₃ and upshifted the d-band center of MAPbI₃. This not only enhanced the piezoelectric response of MAPbI₃ but also promoted the proton transfer during the hydrogen evolution process. Due to the decoration of Fe single atoms, r-MAPbI₃ showed a pronounced H₂ yield of 322.4 μmol g⁻¹ h⁻¹, which was 2.52 times that of MAPbI₃ synthesized using commercially available reagents. This simple yet robust strategy to manufacture MAPbI₃ piezocatalysts paves a novel way to the large-scale and value-added consumption of Pb-containing waste residues.