2 Department of Chemistry, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
Electrode materials play a key role in the development of high-performance supercapacitors, particularly with high energy density, fast charge-discharge capability and long cycling stability needed for the use in portable electronic devices. Recent studies show that two-dimensional (2D) layered materials can decrease the diffusion length of electrolyte ions, increase the contact area with electrolyte as well as improve utilization of active materials, leading to a significant enhancement in supercapacitive performance. Herein, a novel family of 2D layered compounds M(OH)(OCH3) (M=Ni, Co, Mn, or their combined molar fractions) were synthesized and characterized, showing 2D nanosheet structure, tunable composition and promising supercapacitive properties. The relationship between their composition, structure and the capacitive properties is investigated, based on which their composition, structure and supercapacitive performance are optimized. Furthermore, graphene M(OH)(OCH3)/graphene composites were prepared by the self-assembly of exfoliated M(OH)(OCH3) and graphene and used as building blocks in fabrication of all-solid-state supercapacitors, which show the synergetic effect in enhancing the capacitive properties and cycling stability. The results have offered the clues for understanding the electrochemical behaviors of this type of layered compounds and their graphene composites, and could provide new principles and protocols for the development of high performance supercapacitors.
Shi, S.; Xu, C. J.; Yang, C.; Chen, Y. Y.; Liu, J. J.; Kang, F. Y. Sci Rep-Uk 2013, 3. Zhu, Y. Q.; Cao, C. B.; Tao, S.; Chu, W. S.; Wu, Z. Y.; Li, Y. D. Sci Rep-Uk 2014, 4.
Zhiting Liu is a postdoctoral researcher of Chemistry at East China University of Science and Technology in Shanghai and is currently visiting the Nanochemistry Group at DTU Chemistry supported by the Marie-Curie Network Program entitled ElectroNanoMat. She mainly focuses on2D energy storage materials such as graphene and transition metallic compounds. She received his B.S. degree in Chemical Engineering and Technology (2008) and a Ph.D. in Chemical Engineering (2014) from East China University of Science and Technology where she studied the manipulation of Surface Chemistry and Properties of Graphene and its Oxide. Her research results have been published on the international journals such as Carbon, Journal of Catalysis, and Nanotechnology, etc.