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Composites of TiO2-B nanorods and reduced graphene oxide (RGO) were prepared through a simple two-step hydrothermal process followed by subsequent heat treatment in argon. The obtained TiO2-B nanorods had a small size (∼10 nm diameter of the nanorod) and a uniform morphology. Importantly, the synergistic effect of RGO nanosheets and nanostructured TiO2-B leads to electrodes composed of the TiO2-B-RGO nanocomposites which exhibit excellent cycling stability and rate capability (260 mA h g(-1) at 1 C and 200 mA h g(-1) at 2 C after 300 cycles and 140 mA h g(-1) at 20 C).

Hierarchical flower-like Nb2O5 microspheres have been prepared via a facile hydrothermal approach without any additives.

Mesoporous Ni0.85Se nanospheres grown on graphene were synthesized via the hydrothermal approach. Because of the exceptional electron-transfer pathway of graphene and the excellent catalytic ability of the mesoporous Ni0.85Se nanospheres, the nanocomposites exhibited excellent electrocatalytic property as the counter electrode (CE) of dye-sensitized solar cells. More catalytic active sites, better charge-transfer ability and faster reaction velocity of Ni0.85Se@RGO (RGO = reduced graphene oxide) CE led to faster and more complete I3(-) reduction than Pt, Ni0.85Se, and RGO CEs. Furthermore, the power conversion efficiency of Ni0.85Se@RGO CE reached 7.82%, which is higher than that of Pt CE (7.54%). Electrochemical impedance spectra, cyclic voltammetry, and Tafel polarization were obtained to demonstrate positive synergetic effect between Ni0.85Se and RGO, as well as the higher catalytic activity and the better charge-transfer ability of Ni0.85Se@RGO compared with Pt CE.

A new type of hierarchical WO3·H2O hollow microsphere, whose formation was successfully controlled based on the reaction system for preparing simple nanoplates, showed excellent photocatalytic activity for the degradation of dye under visible light.

3D cubic microporous In 2 O 3 has been successfully obtained by calcining the as-synthesized cube In(OH) 3 -InOOH precursor at 300 C for 2 hours. X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) were employed to clarify the structures and morphologies of both the cubic In(OH) 3 -InOOH precursor and cubic In 2 O 3 . The formation mechanisms of the In(OH) 3 -InOOH precursor and cubic In 2 O 3 were investigated. As an important semiconductor photocatalytic material, its photocatalytic properties have been tested. Under the irradiation of UV light, the cubic microporous In 2 O 3 exhibits excellent photocatalytic properties to degrade eosin B (EB), which presents $95% degradation of EB after 3 hours and the degradation rates is 10.5 times that of commercial In 2 O 3 powder. The high separation efficiency of electron-hole pairs results in high photocatalytic activity.Furthermore, the photoluminescent properties of the cubic microporous In 2 O 3 have been investigated as well.

Polysulfide dissolution is one of the inherent challenges in lithium−sulfur batteries (LSBs). The shuttle effect of soluble polysulfide species between the cathode and the anode can cause the loss of active materials and the attenuation of specific capacity in LSBs. Herein, the N-doped porous carbon (NC) nanosheets with uniformly anchored defect-rich MoS 2 nanosheets (MoS 2 /NC) were constructed by a simple and low-cost method. The NC nanosheets facilitate transfer of lithium ion and electron and localize polysulfides via the Li−N chemical bond. The defectrich MoS 2 nanosheets can be used as electrocatalysts to propel polysulfide conversion by abundant catalytic activity sites and thus control the shuttle effect as well as improve cycling performances of LSBs. Consequently, the defect-rich MoS 2 /NC composites as separator modification present a high specific capacity of 1021 mAh g −1 at 0.2 C after 100 cycles and superior long-term performances with enhanced specific capacities of 429 mAh g −1 with a low capacity fading rate of 0.027% per cycle at 5 C after 1000 cycles. The reasonable construct strategy of defect-rich MoS 2 /NC composites is effective in enhancing the electrochemical performances of LSBs and promoting their commercial applications. KEYWORDS: N-doped porous carbon, defect-rich MoS 2 , shuttle effect, electrocatalysis, polysulfides

In this work, we report the synthesis of mesoporous Bi₂S₃ nanorods under hydrothermal conditions without additives, and investigated their catalytic activities as the CE in DSCs by I-V curves and tested conversion efficiency. To further improve their power conversion efficiency, we added different amounts of reduced graphene by simple physical mixing. With the addition of 9 wt% reduced graphene (rGO), the short-circuit current density, open-circuit voltage and fill factor were Jsc = 15.33 mA cm(-2), Voc = 0.74 V and FF = 0.609. More importantly, the conversion efficiency reached 6.91%, which is slightly inferior to the commercial Pt counter electrode (7.44%). Compared to the conventional Pt counter electrodes of solar cells, this new material has the advantages of low-cost, facile synthesis and high efficiency with graphene assistance. To the best of our knowledge, this Bi₂S₃ + 9 wt% rGO system has the best performance ever recorded in all Bi₂S₃-based CEs in the DSCs system.