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Organolead halide perovskites are becoming intriguing materials applied in optoelectronics. In the present work, organolead iodide perovskite (OIP) nanowires (NWs) have been fabricated by a one step self-assembly method. The controllable NW distributions were implemented by a series of facile techniques: monolayer and small diameter NWs were prepared by precursor concentration tuning; NW patterning was achieved via selected area treatment assisted by a mask; NW alignment was implemented by modified evaporation-induced self-assembly (EISA). The synthesized multifunctional NWs were further applied in photodetectors (PDs) and solar cells as application demos. The PD performances have reached 1.32 AW(-1) for responsivity, 2.5 × 10(12) Jones for detectivity and 0.3 ms for response speed, superior to OIP films and other typical inorganic NW based PD performances. An energy conversion efficiency of ∼2.5% has been obtained for NW film based solar cells. The facile fabrication process, controllable distribution and optoelectronic applications make the OIP NWs promising building blocks for future optoelectronics, especially for low dimensional devices.

We report tunable band gaps and transport properties of B-doped graphenes that were achieved via controllable doping through reaction with the ion atmosphere of trimethylboron decomposed by microwave plasma. Both electron energy loss spectroscopy and X-ray photoemission spectroscopy analyses of the graphene reacted with ion atmosphere showed that B atoms are substitutionally incorporated into graphenes without segregation of B domains. The B content was adjusted over a range of 0-13.85 atom % by controlling the ion reaction time, from which the doping effects on transport properties were quantitatively evaluated. Electrical measurements from graphene field-effect transistors show that the B-doped graphenes have a distinct p-type conductivity with a current on/off ratio higher than 10(2). Especially, the band gap of graphenes is tuned from 0 to ~0.54 eV with increasing B content, leading to a series of modulated transport properties. We believe the controllable doping for graphenes with predictable transport properties may pave a way for the development of graphene-based devices.

Single-crystal α-MnO2 nanorods were prepared by hydrothermal reaction of single KMnO4 under acidic conditions. The nanorods have a diameter of 30–70 nm and a length up to 2 µm. The formation mechanism for the α-MnO2 nanorods was investigated. Electrochemical properties of the MnO2 nanomaterials prepared for different hydrothermal times were characterized by galvanostatic charge/discharge tests and cyclic voltammetry (CV) studies. The results indicate that the MnO2 nanorods prepared for 5 and 8 h show fine capacitive behaviour with high specific capacitances of 71.1 and 70.9 F g−1, respectively.

A carbon-free nanocomposite consisting of MoO nanoparticles embedded between MoSe nanosheets, named MoO@MoSe, has been synthesized and demonstrated excellent electrochemical properties for lithium ion batteries. In such a composite, MoSe nanosheets provide a flexible substrate for MoO nanoparticles; while MoO nanoparticles act as spacers to retain the desired active surface to electrolyte and also introduce metallic conduction. In addition, the heterojunctions at the interface between MoSe and MoO introduce a self-built electric field to promote the lithiation/delithiation process. As a result, such lamellar composite has a long cycling stability with a reversible capacity of 520.4 mA h g at a current density of 2000 mA g after 400 cycles and excellent rate performance, which are attributed to the synergistic combination of the two components in nanoscale.

Porous anatase TiO2 spheres with sizes ranging from 150 to 250 nm were synthesized by a rapid microwave treatment of spherical titanium glycolate precursors preformed via an ethylene glycol-mediated sol–gel process. The effects of various experimental conditions on the formation of titanium glycolate precursors and final TiO2 spheres were investigated. A dye-sensitized solar cell (DSSC) assembled with the as-synthesized porous TiO2 spheres as photoanodes exhibits a 5% energy conversion efficiency, which is almost 40% higher than that made of the standard commercial Degussa P25 TiO2 nanopowders.

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TiO is a promising and safe anode material for lithium ion batteries (LIBs). However, its practical application has been plagued by its poor rate capability and cycling properties. Herein, we successfully demonstrate a novel structured TiO anode with excellent rate capability and ultralong cycle life. The TiO material reported here shows a walnut-like porous core/shell structure with hybridized anatase/amorphous phases. The effective synergy of the unique walnut-like porous core/shell structure, the phase hybridization with nanoscale coherent heterointerfaces, and the presence of minor carbon species endows the TiO material with superior lithium storage properties in terms of high capacity (∼177 mA h g at 1 C, 1 C = 170 mA g), good rate capability (62 mA h g at 100 C), and excellent cycling stability (∼83 mA h g was retained over 10 000 cycles at 10 C with a capacity decay of 0.002% per cycle).