Encapsulating MoO2 Nanocrystals into Flexible Carbon Nanofibers via Electrospinning for High-Performance Lithium Storage

Abstract

Design and synthesis of flexible and self-supporting electrode materials in high-performance lithium storage is significant for applications in the field of smart wearable devices. Herein, flexible carbon nanofiber membranes with uniformly distributed molybdenum dioxide (MoO2) nanocrystals are fabricated by a needlefree electrospinning method combined with the subsequent carbonization process, which exhibits outstanding structural stability under abrasion and deformation. The as-fabricated lithium-ion batteries (LIBs) exhibit a high discharge of 450 mAh g−1 after 500 cycles at 2000 mA g−1 by using the MoO2/C nanofiber membrane as the self-supporting anode. Further, the nanofibers structure remains intact after 500 cycles, which reflects the excellent stability of the materials. This study provides a simple and effective method for the preparation of MoO2/C nanofiber materials, which can not only maintain its excellent electrochemical and physical properties, but also easily realize large-scale production. It is undoubtedly beneficial for the development of flexible LIBs and smart wearable devices.

Growth, characterization and performance of bulk and nanoengineered molybdenum oxides for electrochemical energy storage and conversion

“…When, the Li/MoO2@C half cells cycled at 0.5 and 10 A g −1 retain 861 and 312 mAh g −1 capacity after 140 and 268 cycles, respectively. Recently, Zhang et al [515] reported the design and fabrication of a composite, which consists of encapsulated MoO2 nanocrystals into flexible carbon nanofibers, using a needle-free electrospinning method combined with the subsequent carbonization process. The MoO2/C nanofiber membrane as self-supporting anode exhibits a discharge capacity of 450 mAh g −1 after 500 cycles at 2000 mA g −1 .…”

Hetero-Phase MoO2/Cu2–xSe Nanocomposites Distributed in Porous Octahedral Carbon Networks for High-Performance Lithium Storage

“…36,38 The C 1s XPS spectrum is displayed in Figure 1g, and it can be clearly seen that there are three peaks located at 284.6, 285.9, and 288.9 eV, which could be attributed to C� C, C−O, and C�O bonds, respectively. 39,40 The existence of carbon in the MoO 2 /Cu 2−x Se@C octahedron was further evidenced by Raman spectroscopy (Figure S5). There are two obvious characteristic peaks at 1371 and 1595 cm −1 , corresponding to the D peak and G peak of carbon, respectively.…”

“…In addition, there is a weak peak at 943.0 eV in the middle of the two peaks, which indicates that the Cu element mainly exists in the valence state of Cu + . , In the high-resolution Mo 3d spectrum, the peaks are fitted into two parts (Figure e). Two characteristic peaks at 228.9 and 232.5 eV, respectively, belong to Mo 6+ (3d 3/2 ) and Mo 6+ (3d 5/2 ), , while other peaks at 232.1 and 235.8 eV correspond to Mo 4+ (3d 3/2 ) and Mo 4+ (3d 5/2 ), suggesting the surface oxidation of MoO 2 . − As shown in Figure f, the high-resolution O 1s spectrum shows two obvious characteristic peaks at 530.9 and 532.2 eV, which are mainly attributed to Mo–O and C–O bonds, respectively. , The C 1s XPS spectrum is displayed in Figure g, and it can be clearly seen that there are three peaks located at 284.6, 285.9, and 288.9 eV, which could be attributed to CC, C–O, and CO bonds, respectively. , …”

Nanostructured Molybdenum-Oxide Anodes for Lithium-Ion Batteries: An Outstanding Increase in Capacity

“…Table 5 summarizes the electrochemical performance of various MoO 2 anode materials prepared by various synthetic processes [ 107 , 108 , 109 , 110 , 111 , 112 , 113 , 114 , 115 , 116 , 117 , 118 , 119 , 120 , 121 , 122 , 123 , 124 , 125 ]. The different strategies demonstrate the ability to mitigate the particle pulverization as a consequence of Li insertion/extraction and improve the MoO 2 electrochemical performance via the fabrication of nanocomposites including carbonaceous materials.…”