标題: Modulating carbon growth kinetics enables electrosynthesis of graphite derived from CO2 via a liquid-solid-solid process

作者: Yu, R (Yu, Rui); Deng, BW (Deng, Bowen); Du, KF (Du, Kaifa); Chen, D (Chen, Di); Gao, MX (Gao, Muxing); Wang, DH (Wang, Dihua)

來源出版物: CARBON 卷: 184 頁: 426-436 DOI: 10.1016/j.carbon.2021.08.033 出版年: OCT 30 2021

摘要: Highly graphitic carbon materials have gained considerable interests in practical applications, however, an efficient and cost-effective synthesis strategy using low-grade carbonaceous precursors is still in urgent need. In this work, we successfully synthesize well-crystalline graphite derived from CO2 by molten carbonate electrolysis under a mild operating temperature, where the as-formed carbon atoms follow a "dissolution-precipitation" process on a Ni cathode. Attributed to that Ni cathode can in situ act as a solid solvent for periodically accommodating/dissolving the as-formed carbon atoms, deliberately coordinating carbon formation flux with carbon dissolution flux can lead to the consecutive production of highly crystalline graphite, without contamination of transition metal catalyst. It was found that a low carbon deposition current density and a relatively high operating temperature (650-750 degrees C) both facilitate the growth of graphite structures, because a moderate current density enables a suitable carbon flux originating from the electro-reduction of the captured CO2 (in the form of CO(3)(2- )in molten salts), which can more accessibly match the carbon dissolution flux in Ni substrate at an elevated temperature. The thickness of graphite can be easily controlled by electrolysis durations. This work provides a simple strategy to convert CO2 into graphitic carbon products with both promising purity and crystallinity. (C) 2021 Elsevier Ltd. All rights reserved.

作者關鍵詞: Graphene; Growth kinetics; Electrolysis; CO2 conversion; Molten salt

地址: [Yu, Rui; Deng, Bowen; Du, Kaifa; Chen, Di; Gao, Muxing; Wang, Dihua] Wuhan Univ, Sch Resource & Environm Sci, Hubei Int Sci & Technol Cooperat Base Sustainable, Wuhan 430072, Peoples R China.

通訊作者地址: Deng, BW; Wang, DH (通訊作者)，Wuhan Univ, Sch Resource & Environm Sci, Hubei Int Sci & Technol Cooperat Base Sustainable, Wuhan 430072, Peoples R China.

電子郵件地址: bwdeng@whu.edu.cn; wangdh@whu.edu.cn

影響因子：9.594