Electrochemical study on different layers of graphene based TiO2/graphene composites as an anode for lithium-ion batteries

Graphene: Chemistry and Applications for Lithium-Ion Batteries

In the present era, different allotropes of carbon have been discovered, and graphene is the one among them that has contributed to many breakthroughs in research. It has been considered a promising candidate in the research and academic fields, as well as in industries, over the last decade. It has many properties to be explored, such as an enhanced specific surface area and beneficial thermal and electrical conductivities. Graphene is arranged as a 2D structure by organizing sp2 hybridized C with alternative single and double bonds, providing an extended conjugation combining hexagonal ring structures to form a honeycomb structure. The precious structure and outstanding characteristics are the major reason that modern industry relies heavily on graphene, and it is predominantly applied in electronic devices. Nowadays, lithium-ion batteries (LIBs) foremostly utilize graphene as an anode or a cathode, and are combined with polymers to use them as polymer electrolytes. After three decades of commercialization of the lithium-ion battery, it still leads in consumer electronic society due to its higher energy density, wider operating voltages, low self-discharge, noble high-temperature performance, and fewer maintenance requirements. In this review, we aim to give a brief review of the domination of graphene and its applications in LIBs.

Hollow Fe3O4/carbon with surface mesopores derived from MOFs for enhanced lithium storage performance

Hollow metal-organic frameworks (MOFs) and their derivatives have attracted more and more attention due to their high specific surface area and perfect morphological structure, which determine their large potential application in energy storage and catalysis fields. However, few researchers have carried out further modification on the outer shell of hollow MOFs, such as the perforation modification, which will endow hollow nanomaterials derived from MOFs with multifunctionality. In this paper, hollow MOFs of MIL-53(Fe) with perforated outer surface are successfully synthesized by using SiO₂ nanospheres as the template via a self-assembly process induced by the coordination polymerization. The tightly packed mesopore structure makes the carbon outer shell of MOFs thinner, thus realizing the in-situ transformation from MOFs to hollow Fe₃O₄/carbon, which exhibits perfect capacity approaching 1270 mA h g^-1 even after 200 cycles at 0.1 A g^-1, as an anode material in lithium ion batteries (LIBs) application. This research provides a new strategy for the design and preparation of MOFs and their derivatives with multifunctionality for the energy applications.