Nanowires-Assembled TiO2 Nanorods Anchored on Multilayer Graphene for High-Performance Anodes of Lithium-Ion Batteries

Abstract

Multilayer graphene (MLG) prepared via ultrasonic exfoliation has many advantages such as its low-cost and defect-free nature, high electronic conductivity, and large specific surface area, which make it an apt conductive substrate for TiO2 composites. To synthesize graphene/TiO2 hybrids, traditional methods that greatly depend on the chemical bond of oxygen-containing functional groups on graphene with titanium cations are not applicable due to the absence of these functional groups on MLG. In this work, a facile chemical method is developed to directly deposit TiO2 on the MLG surface without the introduction of chemically active groups. With this method, four types of TiO2 materials, that is pure anatase TiO2 nanoparticles, a mixture of anatase TiO2 nanoparticles and rutile TiO2 nanoflowers, pure rutile TiO2 nanoflowers, and pure rutile TiO2 nanorods, are homogeneously anchored on the MLG surface by controlling the amount of HCl in the reactant. Interestingly, the rutile TiO2 nanorods in the TiO2/MLG composite are assembled by many TiO2 nanowires with an ultra-small diameter and ultra-long length, which provides a better synergetic effect for high performances as LIB anodes than other composites. A specific capacity of 631.4 mAh g−1 after 100 cycles at a current density of 100 mA g−1 is delivered, indicating it to be a valuable LIB anode material with low cost and high electrochemical performances.

Spontaneous redox reaction-mediated interfacial charge transfer in titanium dioxide/graphene oxide nanoanodes for rapid and durable lithium storage

“…Among the studied anodes, titanium dioxide (TiO 2 ) has been widely investigated owing to its low cost and environmental friendliness. [7][8][9] Besides, because of the higher voltage platform of titanium dioxide anodes (∼1.7 V vs. Li/Li + ) than that of graphite anodes (∼0.1 V vs. Li/Li + ), the precipitation of lithium dendrites and the formation of a solid electrolyte interface (SEI) film on TiO 2 anodes can be effectively prevented, [10][11][12] which are responsible for a trustworthy safe performance. In particular, volume change (<4%) is small during the lithiation/de-lithiation process, which effectively improves cycling stability.…”

“…Among the studied anodes, titanium dioxide (TiO 2 ) has been widely investigated owing to its low cost and environmental friendliness. 7–9 Besides, because of the higher voltage platform of titanium dioxide anodes (∼1.7 V vs . Li/Li + ) than that of graphite anodes (∼0.1 V vs .…”

Efficient Photocatalytic Core–Shell Synthesis of Titanate Nanowire/rGO

“…This limitation is further exacerbated by the rapid recombination of photogenerated electron-hole pairs and the slow transfer of charge carriers in the bulk and on the surface of the nanostructures [10]. A promising solution has been found in the use of 2D graphene on titanate [22,23], which can significantly increase the photocatalysis activity owing to its large surface area, excellent mobility of its charge carriers, and its controllable bandgap. The resultant narrow bandgaps, short transport distances, and accelerated charge mobility have improved the photocatalytic performance of the graphene-on-titanate [24,25].…”

Effect of the Concentration of Silver Nanoparticles on the Photocatalytic Activity of Titanium Dioxide Nanorods

“…Among the variety of nanostructures, titanium dioxide nanorods (TNR) are the most promising because they have one-dimensional electron transport, high specific surface area and high crystallinity [12][13][14]. At the same time, the possibility of using one-dimensional electron transport will make it possible to somehow reduce the recombination rate of photogenerated TNR charge carriers, but the problem of the absorption capacity of only the ultraviolet region has not yet been resolved.…”