Green synthesis of graphite from CO2 without graphitization process of amorphous carbon

Chu Liang,Shiyou Zheng,Wenkui Zhang,Yang Xia,Jian Chen,Hui Huang,Hongge Pan,Yun Chen,Kai Wang,Yongping Gan,Min Wu,Jun Zhang

doi:10.1038/s41467-020-20380-0

Abstract

Environmentally benign synthesis of graphite at low temperatures is a great challenge in the absence of transition metal catalysts. Herein, we report a green and efficient approach of synthesizing graphite from carbon dioxide at ultralow temperatures in the absence of transition metal catalysts. Carbon dioxide is converted into graphite submicroflakes in the seconds timescale via reacting with lithium aluminum hydride as the mixture of carbon dioxide and lithium aluminum hydride is heated to as low as 126 °C. Gas pressure-dependent kinetic barriers for synthesizing graphite is demonstrated to be the major reason for our synthesis of graphite without the graphitization process of amorphous carbon. When serving as lithium storage materials, graphite submicroflakes exhibit excellent rate capability and cycling performance with a reversible capacity of ~320 mAh g–1 after 1500 cycles at 1.0 A g–1. This study provides an avenue to synthesize graphite from greenhouse gases at low temperatures.

Highlights

Benign synthesis of graphite at low temperatures is a great challenge in the absence of transition metal catalysts
When the CO2‒LiAlH4 sample is heated to 126 °C, the sample temperature jumps to 876 °C in 3 s, implying exothermic nature of the reactions between CO2 and LiAlH4
In summary, we have demonstrated a method for the green synthesis of graphite from CO2 at low temperatures

Summary

Introduction

Benign synthesis of graphite at low temperatures is a great challenge in the absence of transition metal catalysts. We report a green and efficient approach of synthesizing graphite from carbon dioxide at ultralow temperatures in the absence of transition metal catalysts. As a type of crystalline carbon with tunable microstructure and morphology, of which the synthesis procedures generally contain two sequential processes: carbonization of carbon precursors and graphitization of amorphous carbon[19,20,21,22]. We explore a green, ultralow-temperature, and efficient route to synthesize graphite with controllable microstructure and morphology from CO2 without the graphitization process of amorphous carbon. Assynthesized graphite submicroflakes, serving as anode materials for lithium storage, are demonstrated to show excellent rate capability and cycling performance with a reversible capacity of ~320 mAh g–1 at 1.0 A g–1 after 1500 cycles

Methods

Results

Conclusion