Novel In Situ Fabrication of Chestnut-Like Carbon Nanotube Spheres from Polypropylene and Nickel Formate

Abstract

A novel in situ approach to mass fabrication of carbon nanotubes was reported. Composites of polypropylene (PP)/organomontmorillonite (OMMT)/nickel formate (NF) were prepared by mixing these components in a Brabender mixer at an elevated temperature. Chestnut-like carbon nanotube (CNT) spheres were in situ fabricated in high yields by heating the PP/OMMT/NF composites at 900 degrees C without adding any additional pre-synthesized nickel nanocatalysts. The products were studied by X-ray diffractometer (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), Raman spectroscopy, and N2 adsorption-desorption measurements. The results showed that nickel nanoparticles were in situ produced, which catalyzed the formation of multiwalled carbon nanotubes (MWNTs) in an autoclave-like microreactor formed by OMMT. These in situ formed nickel nanoparticles were found to be more catalytically active than pre-synthesized nickel nanocatalysts, resulting in higher yields of CNTs. The obtained CNT spheres have a high surface area, which makes them a good catalyst support. Loading of metal nanoparticles was preliminarily tried, and Pt nanoparticles of ca. 2.65 nm in size were successfully deposited on CNTs. The applications of these nanocatalysts in chemical reactions are currently being studied in our laboratory.

In-situ synthesis of a palladium-polyaniline hybrid catalyst for a Suzuki coupling reaction

“…Unfortunately, aggregation of bare nanoparticles often prohibits the tailoring of particle size [8]. To overcome this problem, catalytic nanoparticles have been immobilized on solid supports, such as carbon [9], titania [10], zeolites [11], alumina [12], silica spheres [13] and polymers [14]. Over recent years, especially following the rapid development of combinatorial chemistry, the use of polymeric supports in organic synthesis has become common practice in constructing small organic molecules [15,16].…”

Converting Waste Plastics into High Yield and Quality Carbon-Based Materials

“…[26][27][28] Chen et al synthesized CNTs, chestnut-like CNTs spheres and carbon nanospheres from catalytic pyrolysis of polypropylene (PP) using different catalyst precursors ( Figure 1). [29,30] In their methods, it is necessary that catalyst precursors were mixed with PP and clay, then such nanocomposites were burned to obtain CNTs. In our previous work, CNTs with various structures were prepared by catalytic decomposition of waste plastics using stainless steel autoclave as reactor.…”

“…[33] Therefore, using waste plastics as inexpensive feedstocks can contribute to the cost reduction of CNTs production, which may accelerate CNTs large-scale use in consumer/industrial products. [27] (b) Chestnut-like carbon nanotube spheres by heating the PP/OMMT/NF composites; [29] (c) Straight and helical CNTs through catalytic decomposition of PE; [31] (d) MCNTs by catalytic decomposition of PP and MA-PP. [33] Preparation of carbon spheres…”

Synthesis and Catalytic Activity of Silicon Nanowires Decorated with Noble Metal Nanoparticles

“…为了解决这个问题, 纳米粒子的催 化剂通常会负载在固体的载体上, 例如碳 [1,2] 、钛 [3] 、 银 [4] 、氧化铝 [5] 、二氧化硅球 [6] 、聚苯乙烯球 [7] 、沸石 [8] 以及蒙脱石 [9] 等. 硅纳米线由于表面易于修饰各种金属粒子, 以及大 的比表面积、良好的稳定性, 引起了人们的极大兴 趣 [10～14] .…”