From biomass to functional crystalline diamond nanothread

Pressure-induced polymerization of 2,5-furandicarboxylic acid to crystalline CNTh. Credit: Dr. Haiyan Zheng

New research from a team of scientists led by Drs. Kuo Li and Haiyan Zheng from the Center for High Pressure Science and Technology Advanced Research (HPSTAR) reported the first synthesis of a three-dimensional crystalline carbon nanothread (CNThs) from a biomass precursor, 2,5-furandicarboxylic acid (FDCA), through [4+2] Diels-Alder reactions.

Crystalline CNTh shows excellent electrochemical performance as an anode material for lithium batteries.

The work is published in the Journal of the American Chemical Society.

Carbon nanothread (CNTh) is a one-dimensional diamond material which has high tensile strength and bending modulus. In 2015, scientists synthesized CNTh for the first time via pressure-induced polymerization of benzene. Later, starting from various aromatic molecules, a series of CNThs were synthesized. However, how to improve the atomical intra-and interthread ordering is a longstanding question for CNTh.

FDCA is one of the top-12 value-added chemicals from sugar and is widely applied in chemical industry. "Compared to benzene, it has fewer possible bonding routes which will help to improve the homogeneity of the CNThs. Besides, its aligned π-π stacking and intermolecular H-bonding in its structure is also critical to obtain the crystalline diamond nanothread. Therefore, the 2,5-furandicarboxylic acid is a better precursor material for CNTh," said Dr. Kuo Li.

In this work, the scientists synthesized the atomically ordered crystalline CNTh with uniform syn-configuration (all the oxygens on one side) by compressing FDCA at ~12 GPa. With the exceptional long-range ordering in the product, they determined the precise crystal structure directly from the X-ray diffraction, showing an obvious contrast to the previously reports of CNThs.

The combination spectroscopy and theoretical simulation show that the FDCA experienced continuous [4+2] Diels-Alder reactions along the stacking direction to form CNTh. Benefiting from the abundant carbonyl groups, the poly-FDCA CNTh has a high specific capacity, excellent coulombic efficiency and rate performance as an anode material of Li-battery.

"The reaction pressure of ~ 12GPa is relatively low," said Dr. Xuan Wang, the lead author of the study. "And this is the first time to use biomass compounds to synthesize the diamond carbon nanothread materials. We believe our study will provide a new route to synthesize advanced functional carbon materials," added Dr. Haiyan Zheng.

Provided by Center for High Pressure Science & Technology Advanced Research