Publications by authors named "Zhefei Sun"

Sluggish redox kinetics and dendrite growth perplex the fulfillment of efficient electrochemistry in lithium-sulfur (Li-S) batteries. The complicated sulfur phase transformation and sulfur/lithium diversity kinetics necessitate an all-inclusive approach in catalyst design. Herein, a compatible mediator with nanoscale-asymmetric-size configuration by integrating Co single atoms and defective CoTe (Co-CoTe@NHCF) is elaborately developed for regulating sulfur/lithium electrochemistry synchronously.

View Article and Find Full Text PDF
Article Synopsis
  • Advancements in microstructured alloying anodes for sodium-ion batteries (SIBs) are crucial for better performance but face issues like mechanical degradation and slow charging due to large volumetric changes and reduced cyclability.
  • A new anode design uses densely packed bismuth embedded in conductive carbon microspheres, showcasing improved mechanical strength and minimal volume swelling after use.
  • This anode exhibits high volumetric capacity, rapid charging capabilities, and excellent cycling stability, making it a promising solution for enhancing the efficiency of SIBs and maintaining performance even under extreme conditions.
View Article and Find Full Text PDF

As the preferred anode material for sodium-ion batteries, hard carbon (HC) confronts significant obstacles in providing a long and dominant low-voltage plateau to boost the output energy density of full batteries. The critical challenge lies in precisely enhancing the local graphitization degree to minimize Na ad-/chemisorption, while effectively controlling the growth of internal closed nanopores to maximize Na filling. Unfortunately, traditional high-temperature preparation methods struggle to achieve both objectives simultaneously.

View Article and Find Full Text PDF
Article Synopsis
  • - The text discusses the importance of compensating for sodium loss in sodium-ion batteries (SIBs) to enhance their energy density, particularly when using hard carbon anodes that have low initial efficiency.
  • - It describes the creation of a presodiation agent, (NaNi□)O (Ni-NaO), which incorporates nickel atoms into the sodium framework to enhance sodium availability and improve battery performance via modified covalent bonding and oxidation activities.
  • - Finally, the implementation of this new presodiation agent in different cathode materials results in significant improvements in energy density, specifically an increase of 23.9% and 19.3% for designated Na-ion full-cells.
View Article and Find Full Text PDF

The development of advanced layered Ni-rich cathodes is essential for high-energy lithium-ion batteries (LIBs). However, the prevalent Ni-rich cathodes are still plagued by inherent issues of chemomechanical and thermal instabilities and limited cycle life. For this, here, we introduce an efficient approach combining single-crystalline (SC) design with in situ high-entropy (HE) doping to engineer an ultrahigh-Ni cobalt-free layered cathode of LiNiMnMgFeTiMoNbO (denoted as HE-SC-N88).

View Article and Find Full Text PDF

As a promising anode material, silicon-carbon composites encounter great challenges related to internal stress release and contact between the composites during lithiation. These issues lead to material degradation and concomitantly rapid capacity decline. Here, we report a type of shell-shell silicon-carbon (SS-Si/C) composite, which consists of a carbon shell tightly coated with a silicon shell.

View Article and Find Full Text PDF

Single crystalline Ni-rich layered oxide cathodes show high energy density and low cost, have been regarded as one of the most promising candidates for next generation lithium-ion batteries (LIBs). Extending the cycling voltage window will significantly improve the energy density, however, suffers from bulk structural and interfacial chemistry degradation, leading to rapidly cycle performance deterioration. Here, we propose a dual-modification strategy to synthesize La doping and LiBO (LBO) coating layers modified LiNiCoMnO (NCM811) by a facile one-step heating treatment processing.

View Article and Find Full Text PDF

Polyethylene oxide (PEO)-based solid-state batteries hold great promise as the next-generation batteries with high energy density and high safety. However, PEO-based electrolytes encounter certain limitations, including inferior ionic conductivity, low Li transference number, and poor mechanical strength. Herein, we aim to simultaneously address these issues by utilizing one-dimensional zwitterionic cellulose nanofiber (ZCNF) as fillers for PEO-based electrolytes using a simple aqueous solution casting method.

View Article and Find Full Text PDF

Zinc-based batteries (ZBBs) have demonstrated considerable potential among secondary batteries, attributing to their advantages including good safety, environmental friendliness, and high energy density. However, ZBBs still suffer from issues such as the formation of zinc dendrites, occurrence of side reactions, retardation of reaction kinetics, and shuttle effects, posing a great challenge for practical applications. As promising porous materials, covalent organic frameworks (COFs) and their derivatives have rigid skeletons, ordered structures, and permanent porosity, which endow them with great potential for application in ZBBs.

View Article and Find Full Text PDF
Article Synopsis
  • Current solid-state batteries struggle to balance ionic conductivity, electrode compatibility, and processability, making the development of efficient electrolytes challenging.
  • By combining features from inorganic and polymer electrolytes, researchers aim to create hybrid solid-state electrolytes that enhance performance.
  • The study demonstrates that copper maleate hydrate nanoflakes can serve as effective lithium ion conductors at room temperature, achieving high ionic conductivity, stability, and compatibility with various electrode materials.
View Article and Find Full Text PDF

Alloying-type antimony (Sb) with high theoretical capacity is a promising anode candidate for both lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs). Given the larger radius of Na (1.02 Å) than Li (0.

View Article and Find Full Text PDF

A commonly used strategy to tackle the unstable interfacial problem between LiAlTi(PO) (LATP) and lithium (Li) is to introduce an interlayer. However, this strategy has a limited effect on stabilizing LATP during long-term cycling or under high current density, which is due in part to the negative impact of its internal defects (eg., gaps between grains (GBs)) that are usually neglected.

View Article and Find Full Text PDF

Developing sacrificial cathode prelithiation technology to compensate for active lithium loss is vital for improving the energy density of lithium-ion battery full-cells. LiCO owns high theoretical specific capacity, superior air stability, but poor conductivity as an insulator, acting as a promising but challenging prelithiation agent candidate. Herein, extracting a trace amount of Co from LiCoO (LCO), a lattice engineering is developed through substituting Li sites with Co and inducing Li defects to obtain a composite structure consisting of (LiCo▫)CO and ball milled LiCoO (Co-LiCO@LCO).

View Article and Find Full Text PDF
Article Synopsis
  • The text discusses the significance of compensating for the loss of lithium in Li-ion batteries to enhance their performance and lifespan.
  • A novel prelithiation agent, (Li Co □ ) O (CLO), is developed by implanting cobalt into lithium oxide, which improves conductivity and allows better lithium mobility.
  • When used with a LiCoO cathode, this agent releases extra lithium to offset losses, resulting in a high-performing battery with impressive energy density and long cycle life.
View Article and Find Full Text PDF

Red phosphorus (P) as an anode material of potassium-ion batteries possesses ultra-high theoretical specific capacity (1154 mAh g ). However, owing to residual white P during the preparation and sluggish kinetics of K-P alloying limit its practical application. Seeking an efficient catalyst to address the above problems is crucial for the secure preparation of red P anode with high performance.

View Article and Find Full Text PDF

The initial Na loss limits the theoretical specific capacity of cathodes in Na-ion full cell applications, especially for Na-deficient P2-type cathodes. In this study, we propose a presodiation strategy for cathodes to compensate for the initial Na loss in Na-ion full cells, resulting in a higher specific capacity and a higher energy density. By employing an electrochemical presodiation approach, we inject 0.

View Article and Find Full Text PDF

Drilling of high-strength T800 carbon fiber reinforced plastic (CFRP) are widely employed in current aviation industry. Drilling-induced damages frequently occur and affect not only the load carrying capacity of components but also the reliability. As one of effective methods to reduce the drilling-induced damages, advanced tool structures have been widely used.

View Article and Find Full Text PDF

Ternary metal sulfides (TMSs), endowed with the synergistic effect of their respective binary counterparts, hold great promise as anode candidates for boosting sodium storage performance. Their fundamental sodium storage mechanisms associated with dynamic structural evolution and reaction kinetics, however, have not been fully comprehended. To enhance the electrochemical performance of TMS anodes in sodium-ion batteries (SIBs), it is of critical importance to gain a better mechanistic understanding of their dynamic electrochemical processes during live (de)sodiation cycling.

View Article and Find Full Text PDF
Article Synopsis
  • * Researchers developed hollow mesoporous carbon capsules that improve wettability with the electrolyte and enhance the performance of the anodes through various characterizations and S-doping.
  • * The new architecture provides excellent battery performance metrics, including high capacity retention over cycles, and stabilizes the carbon anodes against volume changes, suggesting a promising design strategy for better potassium storage.
View Article and Find Full Text PDF

Configurational entropy-stabilized single-phase high-entropy oxides (HEOs) have been considered revolutionary electrode materials with both reversible lithium storage and high specific capacity that are difficult to fulfill simultaneously by conventional electrodes. However, precise understanding of lithium storage mechanisms in such HEOs remains controversial due to complex multi-cationic oxide systems. Here, distinct reaction dynamics and structural evolutions in rocksalt-type HEOs upon cycling are carefully studied by in situ transmission electron microscopy (TEM) including imaging, electron diffraction, and electron energy loss spectroscopy at atomic scale.

View Article and Find Full Text PDF

Zinc ion batteries (ZIBs) have been gradually developed in recent years due to their abundant resources, low cost, and environmental friendliness. Therefore, ZIBs have received a great deal of attention from researchers, which are considered as the next generation of portable energy storage systems. However, poor overall performance of ZIBs restricts their development, which is attributed to zinc dendrites and a series of side reactions.

View Article and Find Full Text PDF
Article Synopsis
  • Constructing 3D skeletons with lithiophilic seeds helps create lithium metal anodes without dendrite formation, but common seeds often clump together during battery cycling.
  • To improve performance, the study introduces intercalation-type lithiophilic seeds, which avoid aggregation due to their stable size and composition changes during use.
  • The new 3D carbon-based host with embedded TiO seeds shows excellent efficiency and durability in lithium metal batteries, confirmed by various microscopical techniques demonstrating the seeds' stability throughout repeated charging and discharging cycles.
View Article and Find Full Text PDF

The interfacial structures and interfacial bonding characteristics between graphene and matrix in graphene-reinforced AlO-WC matrix ceramic composite prepared by two-step hot pressing sintering were systematically investigated. Three interfacial structures including graphene-AlO, graphene-AlOC and graphene-WC were determined in the AlO-WC-TiC-graphene composite by TEM. The interfacial adhesion energy and interfacial shear strength were calculated by first principles, and it has been found that the interfacial adhesion energy and interfacial shear strength of the graphene-AlOC interface (0.

View Article and Find Full Text PDF

Graphene and nano-TiC, which have good reinforcing effects on AlO-based ceramic-tool materials, are generally used as additive phases for ceramics. In this study, nine kinds of samples were sintered, to investigate the effects of graphene and nano-TiC on the reinforcing mechanisms of AlO-based ceramics. The experimental results indicated that adding 0.

View Article and Find Full Text PDF

A PHP Error was encountered

Severity: Warning

Message: fopen(/var/lib/php/sessions/ci_sessionohkqvr3qqs7ejcgl4htb2i57sum4ka6e): Failed to open stream: No space left on device

Filename: drivers/Session_files_driver.php

Line Number: 177

Backtrace:

File: /var/www/html/index.php
Line: 316
Function: require_once

A PHP Error was encountered

Severity: Warning

Message: session_start(): Failed to read session data: user (path: /var/lib/php/sessions)

Filename: Session/Session.php

Line Number: 137

Backtrace:

File: /var/www/html/index.php
Line: 316
Function: require_once