Strengthened d–p Orbital Hybridization on Metastable Cubic Mo₂C for Highly Stable Lithium–Sulfur Batteries

ACS Nano, Год журнала: 2024, Номер unknown

Опубликована: Дек. 13, 2024

Suppressing the lithium polysulfide (LiPS) shuttling as well accelerating conversion kinetics is extremely crucial yet challenging in designing sulfur hosts for lithium–sulfur (Li–S) batteries. Phase engineering of nanomaterials an intriguing approach tuning electronic structure toward regulating phase-dependent physicochemical properties. In this study, a metastable phase δ-Mo2C catalyst was elaborately synthesized via boron doping strategy, which exhibited transfer from hexagonal to cubic structure. The hierarchical tubular δ-Mo2C-decorated N-doped carbon nanotube (δ-B-Mo2C/NCNT) endows fast electron and abundant polar sites LiPSs. First-principles calculations reveal strengthened chemical adsorption capability hybridization between d orbital Mo metal p S atoms LiPSs, contributing higher electrocatalytic activity. Moreover, situ Raman analysis manifests accelerated redox kinetics. Consequently, δ-B-Mo2C/NCNT renders Li–S battery with high specific capacity 1385.6 mAh g–1 at 0.1 C superior rate property 606.3 4 C. Impressively, satisfactory areal 6.95 cm–2 achieved under loading 6.8 mg cm–2. This work has gained research significance design

Язык: Английский

---

Graphitized Layers Encapsulated Carbon Nanofibers as Li‐Free Anode for Hybrid Li‐Ion/Metal Batteries

Small, Год журнала: 2025, Номер unknown

Опубликована: Фев. 2, 2025

Abstract Hard carbon, the Li‐free anode for hybrid Li‐ion/metal batteries (LIB/LMBs), has great potential enhancing fast charging capability, energy density, and battery lifespan. However, low initial Coulombic efficiency (ICE) Li dendrite growth are crucial factors constraining its development. In this work, graphitized layers encapsulated carbon nanofibers (G‐CF) fabricated via Joule heating within 10 s. The C sp2 structure in reduces side reactions with electrolyte, promotes LiC compound formation, improves ions/metal reversibility. inner amorphous boosts capability. As a result, G‐CF attains an 85.2% high ICE exhibits long‐term cycling stability. Under 2 charging, it maintains average of 99.94% 500 mAh g −1 capacity after 200 cycles. Moreover, when N/P ratio is 0.5, G‐CF||NCM811full cell 84.5% provides 530.8 density 365.9 Wh kg at 1C. G‐CF||LFP full can also provide 541.0 under same ratio. A 30 pouch stably cycle over 100 times. This heterogeneous hard design paves revolutionary path manufacturing high‐efficiency anodes LIB/LMBs.

Язык: Английский

---

Nonmetallic High‐Entropy‐Engineered Nanocarbons for Advanced ORR Electrocatalysis

Angewandte Chemie, Год журнала: 2025, Номер unknown

Опубликована: Март 10, 2025

Abstract High‐entropy materials are poised to revolutionize science and industrial applications due their design flexibility, peculiar performance, broad applicability. In this study, we present a proof‐of‐concept high‐entropy engineered nanocarbon (HENC) co‐doped with five nonmetal elements (B, F, P, S, N), synthesized via in situ polymerization modification of ZIF‐8 followed by pyrolysis. The HENC exhibits outstanding performance as electrocatalyst for the oxygen reduction reaction (ORR), activity on par benchmark Pt/C electrocatalysts superior cyclic stability. Simulations all‐site calculations reveal that synergistic effects abundant heteroatoms increased system entropy facilitate formation *O 2 species, N, S acting key active elements, while co‐doping B F further enhances Notably, HENCs have been validated cathode catalysts zinc–air batteries, achieving an impressive peak power density 604 mW cm −2 demonstrating long‐term stability over 16‐day period, outpacing commercial catalyst (542 ). This work not only enriches concept high advances understanding but also opens new avenue development high‐performance low‐cost catalysts.

Язык: Английский

---

Modulating Electronic Structure and Mass Transfer Kinetics via Mo‐Mo₂C Heterostructure for Ampere‐Level Hydrogen Evolution

Advanced Functional Materials, Год журнала: 2025, Номер unknown

Опубликована: Фев. 25, 2025

Abstract Molybdenum carbide (Mo 2 C), known for its platinum‐like electronic structure and excellent corrosion resistance, has demonstrated promising catalytic performance in laboratory tests. However, under industrial harsh conditions, the of Mo C faces constraints due to inherently strong hydrogen adsorption. Additionally, at elevated current densities, rapid depletion active species electrolyte, coupled with gas bubble accumulation, introduce significant mass transport challenges. This work introduces an electrode Mo‐Mo heterostructures supported on a plate (Mo‐Mo C/Mo). Further analyses reveal that incorporating metallic into optimizes C. optimization achieves more balanced adsorption, while also enhancing capacity water adsorption dissociation C, collectively improving activity. Furthermore, this features unique “bush‐like” surface morphology can induce “turbulence” effect electrolyte near surface, facilitating flow transport. As result, C/Mo exhibits high densities (η 1000 = 452 mV). Moreover, resistance robust integration ensure long‐term stability, remaining stable 1.5 A 6 M KOH over extended periods.

Язык: Английский

---

Nonmetallic High‐Entropy‐Engineered Nanocarbons for Advanced ORR Electrocatalysis

Angewandte Chemie International Edition, Год журнала: 2025, Номер unknown

Опубликована: Март 10, 2025

High-entropy materials are poised to revolutionize science and industrial applications due their design flexibility, peculiar performance, broad applicability. In this study, we present a proof-of-concept high-entropy engineered nanocarbon (HENC) co-doped with five nonmetal elements (B, F, P, S, N), synthesized via in situ polymerization modification of ZIF-8 followed by pyrolysis. The HENC exhibits outstanding performance as electrocatalyst for the oxygen reduction reaction (ORR), activity on par benchmark Pt/C electrocatalysts superior cyclic stability. Simulations all-site calculations reveal that synergistic effects abundant heteroatoms increased system entropy facilitate formation *O2 species, N, S acting key active elements, while co-doping B F further enhances Notably, HENCs have been validated cathode catalysts zinc-air batteries, achieving an impressive peak power density 604 mW cm-2 demonstrating long-term stability over 16-day period, outpacing commercial catalyst (542 cm-2). This work not only enriches concept high advances understanding but also opens new avenue development high-performance low-cost catalysts.

Язык: Английский

---

Research Progress of Non‐Noble Metal‐Based Self‐Supporting Electrode for Hydrogen Evolution Reaction at High Current Density

Advanced Functional Materials, Год журнала: 2025, Номер unknown

Опубликована: Март 5, 2025

Abstract Electrocatalytic water splitting has emerged as a key method for large‐scale production of green hydrogen. Constructing efficient, durable, and low‐cost electrocatalysts the hydrogen evolution reaction at high current densities is prerequisite practical industrial applications splitting. Recently, non‐noble metal‐based self‐supporting electrodes have been explored density due to their cost‐effective, conductivity metal substrate, robust interfacial binding between catalyst strong mechanical stability. In this review, recently reported (Ni, Fe, Cu, Co, Ti, Mo, alloy) electrode applied are comprehensively summarized, classified, discussed. Five fundamental design principles such intrinsic activity, abundant active sites, fast electron transfer, mass transport, stability proposed discussed achieve high‐performance under densities. Furthermore, various modification strategies including heteroatom doping, morphology engineering, interface phase strain engineering enhance catalytic activity durability electrode. Finally, challenges prospects designing efficient stable in future This comprehensive overview will provide valuable insight guidance development production.

Язык: Английский

---

Direct Synthesis of Dual Mo-Based Functional Materials Derived from Molybdenite by Molten Salt Paired Electrolysis

ACS Applied Materials & Interfaces, Год журнала: 2025, Номер unknown

Опубликована: Март 28, 2025

A facile synthesis process that facilitates the industrial-scale production of catalysts is prerequisite hydrogen evolution reaction (HER) industry. Molybdenum-based are ideal alternatives for precious-metal-based HER materials; however, they remain challenging in scale-up preparation due to costly and complex Mo sources. Herein, we propose a molten salt paired electrolysis approach synthesize transition-metal-doped Mo2C directly from molybdenite (mainly consisting micrometer-scale MoS2 bulks), an earth-abundant natural ore. Unlike Fe-doped which those transition metal dopants inclined diffuse into inner planes Mo2C, this unique leverages differences diffusion energy barriers, ultimately leading development Ni-doped catalytic materials with specific Ni-enriched interfaces. Owing design structures catalyst, interfacially exhibited promising performance long-term stability. Very interestingly, nanoflakes, as side products, can be collected at anode while was concurrently obtained cathode during electrolytic process. This work not only deepens our knowledge on constructing active-site-enriched interfaces beneficial but also gives clues upcycling raw materials.

Язык: Английский

---

Surface Electron Affinity Modulation: Balancing Iodine Oxidation and Reduction Reaction Kinetics on Mo₂C Cathode Host Catalyst toward Efficient Zn‐I₂ Batteries

Advanced Functional Materials, Год журнала: 2025, Номер unknown

Опубликована: Апрель 13, 2025

Abstract The energy efficiency of aqueous Zn‐I 2 batteries (AZIBs) is traditionally enhanced by cathode host catalysts with high electron affinity, based on the consensus that stronger affinity improves electron‐rich polyiodides adsorption and prevents shuttle effects, thus promoting I /I⁻ conversion reaction. Herein, carbon‐coated Mo C nanocrystals supported carbon spheres (CS/Mo C@C) as an iodine catalyst developed. Interestingly, a deviation from expectation observed: moderate CS/Mo C@C, rather than higher C, actually leads to faster reaction kinetics, while maintaining stable species. This phenomenon can be attributed optimal electron‐donating properties charge transfer dynamics associated lower affinity. Through systematic electrochemical spectroscopic analysis, it uncovered conformal layer covering key adjusting capability, enhancing transfer, improving interfacial kinetics C@C catalyst. Consequently, assembled AZIBs employing C@C/I demonstrate smaller overpotential gap (0.06 V) superior cyclic stability (89.6% capacity retention after 25 000 cycles at 5 A g⁻ 1 ) compared C/I (0.09 V/40.6% 5000 cycles). study highlights significance modulating surface in design for high‐efficiency AZIBs.

Язык: Английский

---

Regulating N-Cu/MoxC interfacial effect coupling β-Mo2C/γ-MoC phase engineering to achieve efficient hydrolysis dissociation and methanol dehydrogenation for hydrogen production

Chemical Engineering Journal, Год журнала: 2024, Номер unknown, С. 155622 - 155622

Опубликована: Сен. 1, 2024

Язык: Английский

---

The composite of TiO2 particles and Na2Ti6O13 whiskers for microwave absorption via a NaCl crystal-assisted sol-gel method

Journal of Alloys and Compounds, Год журнала: 2024, Номер 1010, С. 177450 - 177450

Опубликована: Ноя. 7, 2024

Язык: Английский

---