Metal Catalyst to Construct Carbon Nanotubes Networks on Metal Oxide Microparticles towards Designing High‐Performance Electrode for High‐Voltage Lithium‐Ion Batteries

Abstract

Designing carbon nanotubes (CNTs)-based materials are attracting great attention due to their fantastic properties and greater performance. Herein, a new CNTs network triggered by metal catalysts (e.g., Co, Ni, or Cu) is constructed on metal oxide (e.g., MnO) microparticles, giving rise to a high-performance Co-MnO@C-CNTs anode in lithium-ion batteries (LIBs). An extremely high capacity of 1050 mAh g −1 , extraordinary rate capacities over 10 A g −1 , and a long lifespan over 500 cycles are demonstrated. The great features of Co-MnO@C-CNTs anode are further confirmed in LIBs when the nickel-rich cathode (e.g., LiNi 0.8 Co 0.1 Mn 0.1 O 2 ) is used and charged at a high voltage over 4.5 V. A high-capacity retention of 71.5% can be maintained at 1 C over 150 cycles. The superior performance relates to the CNTs network, which not only acts as an "expressway network" for fast ion/electron transportation but also buffers structural variation. Moreover, the metal nanoparticles can also enhance the electrical conductivity and catalyze the (de-)lithiation of metal oxide, resulting in higher reversibility and long-term cyclability. This study opens a new avenue to prepare CNTs-based functional materials and also explores the potential applications of metal oxide-based anode for high-performance batteries.

Porous Co2VO4 Nanodisk as a High-Energy and Fast-Charging Anode for Lithium-Ion Batteries

“…( 3), the average D Li of PCVO was 6.95 × 10 -10 cm 2 s −1 , showing the same order of magnitude that AIMD simulations have achieved. The D Li of our PCVO ND was higher than that of commercial anode materials (graphite, Li 4 Ti 5 O 12 , and Si) and higher than that of previously reported fast-charging anode materials [28][29][30][31][32] (Fig. 2e), experimentally confirming PCVO ND's feasibility in fastcharging high-energy-density LIBs.…”

NiWO4 Microflowers on Multi-Walled Carbon Nanotubes for High-Performance NH3 Detection

“…At the working temperature, MWCNTs can be deposited and covered on the NiWO 4 surface to form a carbon layer and an MWCNT network. The MWCNTs can be modified with the NiWO 4 particles to enhance the gas sensitivity . The morphology of NiWO 4 MFs and N 2 H 4 ·H 2 O/NiWO 4 (0–0.7) mL was examined by SEM, as shown in Figure b–i, in which the spatial shape, size, and sample distribution of the samples are found to vary with increasing added volumes of N 2 H 4 ·H 2 O.…”

“…Compared with single gas-sensitive materials, nanomaterials have higher catalytic activity and have good stability in air and relative humidity. − Through the construction of heterojunctions, the performance of the sensor is improved, and the application of the material in the field of gas sensors is enriched. From the perspective of energy consumption and portability, this is very promising. − …”

Synthesis of a High-Capacity α-Fe2O3@C Conversion Anode and a High-Voltage LiNi0.5Mn1.5O4 Spinel Cathode and Their Combination in a Li-Ion Battery

“…Electric vehicles (EVs), hybrid-EVs (HEVs), and plug-in HEVs are predominantly powered by the most common version of the lithium-ion battery, that is, the one combining a graphite anode with a layered transition-metal-oxide cathode and employed in common portable electronics. − This system is based on the electrochemical (de)­insertion of lithium into and from the electrode materials and can typically store ca. 250 W h kg –1 for a high number of charge/discharge cycles. , Graphite uptakes Li + delivering a capacity of 372 mA h g –1 , which is limited by the amount of alkali-metal ions stored within the carbon layers, reaching a maximum of 0.16 Li-equivalents per mole of C, that is, according to the LiC 6 chemical formula. , Transition-metal oxides react in the cell by an electrochemical conversion pathway mainly occurring below 1.5 V versus Li + /Li and involving a multiple exchange of electrons, which ensures a higher capacity than that of graphite. − However, this intriguing class of materials intrinsically suffers from poor electrical conductivity and a large volume change throughout the electrochemical process, which causes the voltage hysteresis and rapid cell decay upon cycling . A suitable strategy to mitigate the various issues hindering the efficient use of these alternative anodes is represented by engineering nanostructured oxides with an increased active surface .…”