By Josh Perry, Editor
Carbon nanomaterials have excited scientists around the world because of their unique properties and numerous potential applications, but the complicated processes for creating them have hindered their use.
Schematic illustration of the preparation process of CMs and structures of the investigated SOMs for the CM preparation. (YU Shuhong/USTC)
Researchers at the University of Science and Technology of China (USTC) in Hefei have proposed a new approach that simplifies the process and is versatile enough to create nanomaterials with the desired properties.
According to a report from the university, scientists used transition metal-assisted carbonization to prepare functional carbon nanomaterials from small organic molecules.
“Small organic molecules (SOMs) as precursors for preparing CMs have some distinct advantages, such as common availability, relatively low cost, and diverse element species with various contents,” the article explained. “Previous efforts on the transformation of SOMs into CMs almost relied on harsh synthesis conditions, e.g. pyrolysis in sealed reactors, chemical vapor deposition, or salt-melt-based ionothermal carbonization, due to the high volatility of SOMs at evaluated temperatures.”
To address these concerns, researchers used transition metals to catalyze the formation of thermally-stable intermediate polymeric structures, which avoided direct sublimation during heating and produced high carbon yields.
“Researchers have found that totally 15 SOMs and nine TMSs can be employed as carbon precursors and catalysts respectively for preparing CMs,” the article continued. “Besides, two hard templates can used in the method to enhance the porosity of obtained CMS. All of research results indicate that the method is a simple, effective, and versatile method to prepare CMs.”
The carbon nanomaterials had three different microstructures depending on the molecular structure of the SOM (bamboo-like multi-walled carbon nanotube, micrometer-sized nanosheets and irregular particles). They also demonstrated the desired properties.
The research was recently published in Science Advances. The abstract stated:
“Nanostructured carbon materials with large surface area and desired chemical functionalities have been attracting considerable attention because of their extraordinary physicochemical properties and great application potentials in catalysis, environment, and energy storage. However, the traditional approaches to fabricating these materials rely greatly on complex procedures and specific precursors.
“We present a simple, effective, and scalable strategy for the synthesis of functional carbon materials by transition metal–assisted carbonization of conventional small organic molecules. We demonstrate that transition metals can promote the thermal stability of molecular precursors and assist the formation of thermally stable polymeric intermediates during the carbonization process, which guarantees the successful preparation of carbons with high yield.
“The versatility of this synthetic strategy allows easy control of the surface chemical functionality, porosity, and morphology of carbons at the molecular level. Furthermore, the prepared carbons exhibit promising performance in heterogeneous catalysis and electrocatalysis.”