School of Materials Science and Engineering, Beihang University , 37 Xueyuan Road, Beijing 100191, People's Republic of China.
ACS Appl Mater Interfaces. 2014 Feb 26;6(4):2561-7. doi: 10.1021/am404988b. Epub 2014 Feb 11.
In this study, a simple and reproducible synthesis strategy was developed to fabricate mesoporous carbon nanofibers (MCNFs) by using dual hard templates, a porous anodic aluminum oxide (AAO) membrane, and colloidal silica (Ludox TM-40). By using commercial templates, and removing AAO and the silica simultaneously, the synthesis procedures for MCNFs are greatly simplified without the need for separate preparation or the removal of templates in sequence. With phenol resin as a carbon precursor, the as-prepared MCNFs material reveals not only high surface area and mesoporous volume but also hierarchical nanostructure composed of hollow macrochannels derived from the AAO template, large mesopores (ca. 22 nm) from the removal of silica particles and micropores from the carbonization of phenol resin. Such unique surface and structural characteristics could provide a large quantity of active sites for Li storage and facilitate fast mass transport. Moreover, a one-dimensional (1D) carbon nanofiber (CNF) nanostructure favors fast electron transfer. The as-prepared MCNF anode demonstrates ultrahigh lithium storage capacity particularly at high rates, which is much higher than that reported for the commercial graphite and also significantly higher than other nanostructured carbon materials, such as ordered mesoporous carbon CMK-3 and ordered multimodal porous carbon (OMPC).
在这项研究中，开发了一种简单且可重现的合成策略，通过使用双硬模板（多孔阳极氧化铝（AAO）膜和胶体二氧化硅（Ludox TM-40））来制造介孔碳纳米纤维（MCNFs）。通过使用商业模板，并同时去除 AAO 和二氧化硅，MCNFs 的合成过程大大简化，无需单独制备或顺序去除模板。以酚醛树脂为碳前体，所制备的 MCNFs 材料不仅具有高比表面积和介孔体积，而且还具有由 AAO 模板衍生的中空大孔道、由去除二氧化硅颗粒形成的大介孔（约 22nm）和由酚醛树脂碳化形成的微孔组成的分级纳米结构。这种独特的表面和结构特征可为锂存储提供大量活性位点，并促进快速传质。此外，一维（1D）碳纳米纤维（CNF）纳米结构有利于快速电子转移。所制备的 MCNF 阳极在高电流密度下表现出超高的锂存储容量，远高于商业石墨的报道值，也明显高于其他纳米结构碳材料，如有序介孔碳 CMK-3 和有序多模态多孔碳（OMPC）。
