Free‐Standing Carbon Nanofibrous Films Prepared by a Fast Microwave‐Assisted Synthesis Process

Abstract

Carbon nanofibrous (CNF) films are of great interest for various applications, e.g., as substrates for electrodes, sensors, or catalysts. Here, a fast microwave‐assisted synthesis is reported to fabricate square‐centimeter large free‐standing carbon nanofibrous films of approximately 10 μm thickness utilizing nickel‐based catalysts and ethanol as carbon source. The obtained CNF coatings exhibit a good stability and partial self‐delamination from the substrate is observed, which enables their easy detachment from the substrate without the need for further treatment. Scanning electron microscopy is applied to investigate the morphology of the films and to develop a growth model.

Synthesis and Modification of Carbon Nanomaterials utilizing Microwave Heating

“…D) A set‐up including a commercial single‐mode microwave reactor and liquid carbon sources for the synthesis of CNTs on catalyst‐coated substrates. E) Top‐view of a CNF coating and F) cross‐section of a striped‐off CNF film . G,H) Patterned nanofiber assemblies with small structural size and good selectivity.…”

“…Furthermore, utilizing this process, 10 μm‐thick large‐area carbon nanofibrous films were grown from a nickel acetate catalyst by MW irradiation at 250 W for only 1 min. The CNF coatings could be easily detached from the substrate due to the up‐arching of the catalyst layer during its reduction and the subsequent growth of CNFs from both sides of the catalyst layer (Figure E,F) …”

“…Different tools and tricks have been reported to overcome these safety issues. The applied precautions range from submerging quartz ampoules in water to decrease the radiation that reaches the sample, over introducing a quartz‐glass inlay within the borosilicate glass to prevent contact between highly absorbing samples and the glass wall of the vial, up to flattening the corners of highly microwave‐absorbing substrates to avoid hot‐spot formation. Additionally, MW irradiation can be applied in short intervals with an intermittent cooling time to prevent overheating and the breaking of the reaction vial, or active cooling can be used.…”

Ultrarapid Multimode Microwave Synthesis of Nano/Submicron β-SiC

“…In the material manufacturing sector, energy efficiency, sustainability and economic viability have become increasing important to the industry and society [ 1 ]. Recently, microwave heating has been found to offer faster, simpler and more cost-effective processes for material manufacture, with the result that it is now widely used for chemical synthesis, particularly for the preparation of novel functional materials [ 2 , 3 , 4 , 5 ]. One such material is Silicon carbide (SiC), an important ceramic material that is in high demand.…”

Microwave-assisted Synthesis of Semiconductor Nanomaterials for Energy Storage

“…Microwave irradiation as an inexpensive, quick, clean, and versatile technique can facilitate mass production in a short time with little energy consumption and form an intimate contact between the components [7][8][9][10]. Many semiconductor nanomaterials with different morphologies such as nanorods, nanowires, nanofibers, nanotubes, nanosheets and nanoparticles have been synthesized by the microwaveassisted method [11][12][13][14][15][16][17][18][19][20][21][22][23].…”