Reduction of graphene oxide (GO) is a promising low-cost synthetic approach to bulk graphene, which offers an accessible route to transparent conducting films and flexible electronics. Unfortunately, the release of oxygen-containing functional groups inevitably leaves behind vacancies and topological defects on the reduced GO sheet, and its low electrical conductivity hinders the development of practical applications. Here, we present a strategy for real-time repair of the newborn vacancies with carbon radicals produced by thermal decomposition of a suitable precursor. The sheet conductivity of thus-obtained single-layer graphene was raised more than six-fold to 350-410 S/cm (whilst retaining 〉96% transparency). X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy revealed that the conductivity enhancement can be attributed to the formation of additional sp2-C structures. This method provides a simple and efficient process for obtaining highly conductive transparent graphene films.
Boya DaiLei FuLei LiaoNan LiuKai YanYongsheng ChenZhongfan Liu
The design and fabrication of nanostmctures based on titanium dioxide (TiO2) have attracted much attention because of their low cost, non-toxicity, stability, and potential applications in industry and technology. Recently, one-dimensional (1 D) struc- tured titanates have been used as titanium source to prepare TiO2 nanostructures with various crystalline phases, shapes, sizes, exposed facets, and hierarchical structures. Among the synthetic strategies, hydrothermal method is a facile route to controlla- ble preparation of well-crystalline TiO2 in one step. Herein, we review our recent progress in transferring 1D titanates into TiO2 nanostructures through hydrothermal method, including the transformation mechanism and applications.