Flexible Freestanding MoO_3−x–Carbon Nanotubes–Nanocellulose Paper Electrodes for Charge‐Storage Applications

Abstract

Herein, a one‐step synthesis protocol was developed for synthesizing freestanding/flexible paper electrodes composed of nanostructured molybdenum oxide (MoO3−x) embedded in a carbon nanotube (CNT) and Cladophora cellulose (CC) matrix. The preparation method involved sonication of the precursors, nanostructured MoO3−x, CNTs, and CC with weight ratios of 7:2:1, in a water/ethanol mixture, followed by vacuum filtration. The electrodes were straightforward to handle and possessed a thickness of approximately 12 μm and a mass loading of MoO3−x–CNTs of approximately 0.9 mg cm−2. The elemental mapping showed that the nanostructured MoO3−x was uniformly embedded inside the CNTs–CC matrix. The MoO3−x–CNTs–CC paper electrodes featured a capacity of 30 C g−1, normalized to the mass of MoO3−x–CNTs, at a current density of 78 A g−1 (corresponding to a rate of approximately 210 C based on the MoO3 content, assuming a theoretical capacity of 1339 C g−1), and exhibited a capacity retention of 91 % over 30 000 cycles. This study paves the way for the manufacturing of flexible/freestanding nanostructured MoO3−x‐based electrodes for use in charge‐storage devices at high charge/discharge rates.

Advanced Nanocellulose‐Based Composites for Flexible Functional Energy Storage Devices

“…Distinct interactions including inductive interaction, electrostatic interaction, exchange repulsion, and noncovalent interaction could play important roles for preparing nanocellulose‐based composites. [ 100,122–124 ] For example, CNF can be mixed with carbon nanomaterials (CNTs and graphene) to generate uniform dispersions to prepare nanocellulose‐supported composites. [ 125,126 ] Shao and co‐workers prepared nonwoven macrofiber mats from the composite solutions of CNF/SWCNTs by wet spinning, which promoted the arrangement of SWCNTs along the axial direction in the macrofiber.…”

On the Capacities of Freestanding Vanadium Pentoxide–Carbon Nanotube–Nanocellulose Paper Electrodes for Charge Storage Applications

“…The synthesis process was robust and could be scaled-up to yield 50 g. [57] The paper electrodes were fabricated similar to the previously reported protocol. [51,52,56] In particular, 70 mg of V 2 O 5 ⋅ nH 2 O nanosheet powder, 20 mg of multi-walled CNTs, and 10 mg of CC were dispersed in a waterethanol mixture (60 mL of water and 20 mL of ethanol) and sonicated for 20 min. The formed mixture was filtrated under vacuum on a polypropylene filter to produce a paper sheet.…”

“…[5,[53][54][55] Recently, this approach was also used in the manufacturing of nanostructured reduced molybdenum trioxide MoO 3-x -CNT-nanocellulose paper electrodes, which were found to show fast charge and discharge rates in supercapacitor applications (e.g., exhibiting the capacities of 30 C g À1 at a current density of 78 A g À1 ). [56] As it is reasonable to assume that this synthesis approach can also be used together with other solution-processable nanostructured materials, this possibility should, consequently, be further investigated.…”

Acetonitrile‐Based Electrolytes for Rechargeable Zinc Batteries

“…The research interest in rechargeable batteries and supercapacitors keeps growing due to their application in a variety of technologies such as portable electronic devices, hybrid vehicles, grid storage, and so on. [ 1–8 ] Li‐ion batteries have been developed to commercial application over last 30 years; [ 9–12 ] however, rechargeable nonaqueous batteries based on multivalent ions (e.g., Mg 2+ , Ca 2+ , and Zn 2+ ) have attracted a lot of interest in the last few years due to their abundancy in nature and their potential to provide a reasonable energy density compared with the state‐of‐art Li‐ion batteries. [ 13–17 ] Among them, nonaqueous Zn batteries are interesting to consider, as metallic zinc anode has a higher volumetric capacity compared with metallic Mg and Ca anodes (5851 mAh cm −3 for Zn compared with 3833 and 2073 mAh cm −3 for Mg and Ca, respectively).…”