Precise CO₂ Reduction for Bilayer Graphene

Abstract

It is of great significance to explore unique and diverse chemical pathways to convert CO 2 into high-value-added products. Bilayer graphene (BLG), with a tunable twist angle and band structure, holds tremendous promise in both fundamental physics and next-generation high-performance devices. However, the π-conjugation and precise two-atom thickness are hindering the selective pathway, through an uncontrolled CO 2 reduction and perplexing growth mechanism. Here, we developed a chemical vapor deposition method to catalytically convert CO 2 into a high-quality BLG single crystal with a room temperature mobility of 2346 cm 2 V –1 s –1 . In a finely controlled growth window, the CO 2 molecule works as both the carbon source and the oxygen etchant, helping to precisely define the BLG nucleus and set a record growth rate of 300 μm h –1 .

Fast synthesis of large-area bilayer graphene film on Cu

“…1g ). Note that the original references are also listed in Supplementary Table 1 with more details 9 , 10 , 17 , 21 , 22 , 32 – 52 . The CO 2 -assisted strategy also exhibits excellent scalability and compatibility with the growth of large-area graphene on Cu foils.…”

“…Carbon species can either diffuse from the edge of the MLG domains to be consumed in the nucleation and growth of second layers 17 , 18 or diffuse across the Cu bulk to supply the growth of the second layer on the other side of the Cu foil 19 , 20 . However, the reported bilayer coverage of graphene on Cu is still less than 95% 21 , and several hours are required for the growth 22 , 23 . This is because the second-layer graphene usually nucleates underneath the first-layer graphene, resulting in the difficulty in the continuous supply of active carbon species 16 .…”

“…In detail, CO 2 can be utilized for the pre-treatment of commercial Cu substrates based on its selective etching ability of the disordered carbon impurities 26 , 27 or for growing graphene as the carbon source 28 . However, when CO 2 is employed as a carbon source, additional catalysts, such as Ni/Al 2 O 3 21 , 28 and CuPd 29 , or special treatment of the substrates 30 are usually required, which might hinder compatibility with the mass production processes. In all, even though isolated MLG domains 28 , continuous MLG films 26 , 27 , and isolated BLG domains 21 have been successfully grown based on CO 2 , till now, the controlled preparation of large-area high-quality continuous BLG on Cu has not been achieved yet.…”

Turning CO2 into sustainable graphene: a comprehensive review of recent synthesis techniques and developments

“…In one of the work, Wei et al utilized the CO 2 derived graphene by demonstrating its remarkable ability to keep its performance over time, showing consistent energy storage capacity of 130 mA•h•g −1 even after undergoing 1000 cycles at a current density of 1.0 A•g −1 to be used for lithium-ion battery [149]. In another work, Gong et al showed that bilayer graphene exhibits significant promise for next-generation electrical and twistronics devices due to its configurable band-gap and favorable properties [179]. Despite the numerous advancements in this field, a comprehensive review of the processing methods for CO 2 -based nanostructures and their applications in energy-related contexts has yet to be provided in the literature.…”

“…176,[178][179][180] Dye-sensitize solar cells and perovskite solar cells Photovoltaic energy conversion[154,181,182] Environmental remediation Sustainable practices, eco-friendly technologies[183][184][185] …”