An organic solvent-assisted intercalation and collection (OAIC) approach for preparing Ti 3 C 2 T x (MXene) was developed.
The features of OAIC approach are the low requirement for facility, gram-level preparation with remarkable yield and easy control over the dimension of Ti 3 C 2 T x flakes.
The Ti 3 C 2 T x flakes prepared by OAIC approach showed the outstanding capacitive and rate performance.
Xiaolong Lu,Rongguo Wang,Fan Yang,Weicheng Jiao,Wenbo Liu,Lifeng Hao,Xiaodong He
Lots of top-down approaches by weakening the van der Waals interaction between adjacent layers and breaking up the covalent chemical bonds in each layer have been reported to prepare QDs of layered materials due to the stacked structures. However, much attention has been focused on graphene and layered transition-metal dichalcogenides (TMDs), seldomly on layered transition-metal oxides (TMOs). Herein, a modified top-down method combining intercalation and thermal exfoliation is reported to prepare high-yield QDs of layered MoO3. Alkylamine was first intercalated into MoO3 layers to weaken the van der Waals forces. Then, the covalent bonds in each MoO3 layer were broken down under a sudden increase in gas pressure generated by the decomposition of alkylamines after rapid heating. These fractured particles were further incised to QDs by sonication. The as-prepared MoO3 QD dispersion showed a plasmon resonance after simulated solar light illumination. Surprisingly, their plasmon peak red shifted with an extended illumination time, which was different from the reported MoO3 nanosheets. This reported method is expected to extend to other QDs of layered materials providing that their bulk materials can also be intercalated.
Taotao Sun,Liguo Yue,Ning Wu,Mengni Xu,Wenhu Yang,Hao Guo,Wu Yang
High-performance electrode materials were obtained by isomorphism and intercalation methods, resulting in multi-types of redox reaction centers and a bridge for charge transfer. Some of the Co ions (clusters) were replaced by Ni ions with little difference in radius and different types of redox reactions were constructed. At the same time, the introduction of 2-methylbenzimidazole in the intercalation of two-dimensional (2D) Ni/Co-MOF accelerated the charge transfer. The synthetic composite electrode material exhibited high specific capacitance of 2422.7 F g−1 at a current density of 1.0 A g−1 in three systems and cycle retention of 86% after 3000 cycles. An asymmetric supercapacitor device assembled with the composite material and activated carbon exhibited a maximum energy density of 82.8 W h kg−1 at a power density of 700 W kg−1, showing that the composite has good potential application value.