Date Published: March 25, 2018
Publisher: John Wiley and Sons Inc.
Author(s): Peng Ge, Hongshuai Hou, Xiaoyu Cao, Sijie Li, Ganggang Zhao, Tianxiao Guo, Chao Wang, Xiaobo Ji.
Different dimensions of carbon materials with various features have captured numerous interests due to their applications on the tremendous fields. Restricted by the raw materials and devices, the controlling of their morphology is a major challenge. Utilizing the catalytic features of the intermediates from the low‐cost salts and polymerization of 0D carbon quantum dots (CQDs), 0D CQDs are expected to self‐assemble into 1/2/3D carbon structures with the assistance of temperature‐induced intermediates (e.g., ZnO, Ni, and Cu) from the salts (ZnCl2, NiCl2, and CuCl). The formation mechanisms are illustrated as follows: 1) the “orient induction” to evoke “vine style” growth mechanism of ZnO; 2) the “dissolution–precipitation” of Ni; and 3) the “surface adsorption self‐limited” of Cu. Subsequently, the degree of graphitization, interlayer distance, and special surface area are investigated in detail. 1D structure from 700 °C as anode displays a high Na‐storage capacity of 301.2 mAh g−1 at 0.1 A g−1 after 200 cycles and 107 mAh g−1 at 5.0 A g−1 after 5000 cycles. Quantitative kinetics analysis confirms the fundamentals of the enhanced rate capacity and the potential region of Na‐insertion/extraction. This elaborate work opens up an avenue toward the design of carbon with multidimensions and in‐depth understanding of their sodium‐storage features.
Carbon, as most closely related to human, has been distributed spaciously in the nature, and then spontaneously devoted to enormous attentions in physical and chemical properties. Interestingly, various atomic hybrid orbitals were observed, including sp, sp2, and sp3 characteristics.1 Moreover, the anisotropy of crystal and other arrangements are dominated by that of sp2, giving rise to the innumerable characteristics. In fact, carbon is unique among total elements as the single unit to form 0D fullerenes,2 1D carbin and nanotube,3 2D graphene sheets and 3D diamond crystal,4 which are utilized in a myriad of applications, such as biosensors, catalyst, renewable energy storage, and so on.[[qv: 4b]] In addition, allotropes of carbon have various properties, from hard (diamond) to soft (graphite), from insulative (diamond) to semiconductive (graphite) and conductive (graphene), and from light absorbing (graphite) to diaphanous (diamond).5 Considering its fascinating potential, numerous efforts were further made for carbon to explore different dimensions, and great progress was achieved as expected.6
In summary, controlling 1D CNF, 2D CNS, and 3D CFW is effectively addressed via the aid of temperature‐induced intermediates of salts and the self‐assembly of 0D CQDS. The catalytic characteristics of the reactant production (ZnO, Ni, and Cu) are vital for the in situ construction of multidimensional carbon samples through the “orient induction” of ZnO, the “dissolution–precipitation” of Ni, as well as the “surface adsorption self‐limited” of Cu, further revealing that lattice spaces, the degree of graphitization, effective defects, and special surface area can be effectively manipulated. The formation mechanism of 1D CNF was further explored and deemed as the “vines’ style” growth mechanism triggered by the high energy from the improved temperature. As expected, thanks to theses structure advantages, when 1/2/3D samples are used as anodes for SIBs, the electrochemical properties were greatly enhanced. 1D CNF shows the high reversible capacity of 324.9 mAh g−1 at 0.1 A g−1, and it retains 301.2 mAh g−1 after 200 cycles, as well as the excellent capacity (107 mAh g−1 at 5.0 A g−1 after 5000 cycles). Moreover, 2D CNS and 3D CFW display the good rate performance, delivering Na‐storage capacities of 92.2 and 90.9 mAh g−1 at 5.0 A g−1 after 3000 cycles. The pseudocapacitive contributions are quantificationally analyzed to confirm the fundamental point of the fast Na+ storage for 1D CNF. The construction of multidimensional carbon samples from the catalytic features shed light on the preparation of carbon structure and wide application.
All the chemicals in this work were obtained from the Aladdin and used without any purification.
The authors declare no conflict of interest.