Upcycling of Waste Plastic into Hybrid Carbon Nanomaterials

Abstract

these 1D carbon nanomaterials include carbon nanotubes (CNTs), both single-and multi-walled, as well as ribbon-and platelike carbon nanofibers, bamboo-like carbon nanotubes, cup-stacked carbon nanofibers, and many more. [7][8][9][10] 1D materials are used extensively in composites, coatings, sensors, electrochemical energy storage, and electrocatalysts, capitalizing upon their strength, conductivity, low density, broadband electromagnetic absorption, high surface area, and chemical robustness. [11][12][13][14] Due to their broad utility and scientific interest, identifying new methods of synthesizing 1D carbon materials remains critical. The majority of synthetic strategies to form 1D carbon materials, including arcdischarge, laser ablation, chemical vapor deposition, plasma torch, and high partial pressure carbon monoxide involve the mobilization of carbon atoms in feedstocks on the surface of a catalytic metal which then grow into a graphitic 1D morphology. [15] These current methods often result in mixtures of 1D materials and amorphous carbon that require separation, and 1D materials syntheses often suffer from low production rates of <1 g h −1 . [16][17][18] Some recent work has focused on converting waste plastic into higher value carbon nanomaterials, inspired by the low Graphitic 1D and hybrid nanomaterials represent a powerful solution in composite and electronic applications due to exceptional properties, but large-scale synthesis of hybrid materials has yet to be realized. Here, a rapid, scalable method to produce graphitic 1D materials from polymers using flash Joule heating (FJH) is reported. This avoids lengthy chemical vapor deposition and uses no solvent or water. The flash 1D materials (F1DM), synthesized using a variety of earth-abundant catalysts, have controllable diameters and morphologies by parameter tuning. Furthermore, the process can be modified to form hybrid materials, with F1DM bonded to turbostratic graphene. In nanocomposites, F1DM outperform commercially available carbon nanotubes. Compared to current 1D material synthetic strategies using life cycle assessment, FJH synthesis represents an 86-92% decrease in cumulative energy demand and 92-94% decrease in global-warming potential. This work suggests that FJH affords a cost-effective and sustainable route to upcycle waste plastic into valuable 1D and hybrid nanomaterials.

Advancements in catalysis for plastic resource utilization

“…57 Wyss et al proposed a method for rapid production of 1D graphite materials from waste plastics by optimizing the heat source with flash joule heating (FJH). 58 In just a few milliseconds at temperatures above 3100 K, the plastic polymer rapidly reconstitutes into highly ordered sp 2 heterogeneous flakes, bypassing the need for lengthy chemical vapor deposition processes. On top of thermal cracking, catalysis can further enhance the efficiency and product selectivity of plastic cracking, as will be highlighted in the next section.…”

In Situ Generation of Flash Graphene Supported Spherical Bismuth Nanoparticles in Less than 200 ms for Highly Selective Carbon Dioxide Electroreduction

“…Figure 1b presents the real-time temperature, current, and voltage data recorded during the experi- Figure 1d displays the Raman spectrum of CB, revealing the detected signals of high-intensity D band (∼1324 cm −1 ) and G band (∼1589 cm −1 ). 19 The as-synthesized Bi-NPs/FG sample retains the sharp G peak and shows a characteristic 2D peak (∼2738 cm −1 ) corresponding to the second-order zone boundary phonons of graphene, while the D peak is strongly suppressed. The intensity ratio of I 2D and I G is close to 1.0, indicating a good quality and few layered characteristics of graphene sheets, respectively.…”

“…Figure d displays the Raman spectrum of CB, revealing the detected signals of high-intensity D band (∼1324 cm –1 ) and G band (∼1589 cm –1 ) . The as-synthesized Bi-NPs/FG sample retains the sharp G peak and shows a characteristic 2D peak (∼2738 cm –1 ) corresponding to the second-order zone boundary phonons of graphene, while the D peak is strongly suppressed.…”

“…We propose a solution to this bottleneck by merging Bi nanostructures with graphene to fabricate a matrix and metal interface composite, thereby benefiting the further enhancement of electrocatalytic performance toward the CO 2 RR. As an emerging technique of electrothermal synthesis, the flash Joule heating (FJH) method was first reported by Tour group in 2020, and it has since found many application scenarios to date, including massive production of flash graphene (FG), , transforming polymers into graphitic 1D materials, urban mining from the wastes, , high-performance supercapacitors, and electrochemical oxygen reduction reaction (ORR) . Beyond the conventional synthetic methods for electrode materials, the FJH technique presents several significant advantages, such as a rapid reaction process, ease of operation, and batch production of high-quality FG in high yield.…”

Replacement of Concrete Aggregates with Coal-Derived Flash Graphene

“…The resulting FG is turbostratic and more easily dispersed in composites than graphene produced from exfoliation of graphite . A variety of other applications have been explored for FJH, including synthesis of hybrid carbon nanomaterials, , doped materials, − anode recycling, and heavy metal removal from coal fly ash . Coal materials have been demonstrated to be excellent feedstocks for FG due to their high carbon content.…”