Lithium-sulfur (Li-S) batteries have drawn extensive attentions due to their high energy density, environmental friendliness and low cost. In this study, three-dimensional (3D) graphene/S hybrid (G/S) is prepared by a one-pot hydrothermal method together with redox reaction between S-based compound and graphene oxide (GO). G/S has a three dimensional porous structure, where graphene is interconnected with each other forming a 3D conductive network. It demonstrates that the pore structure of G/S can be well controlled by optimizing the drying method of the 3D graphene-based materials. Freeze drying and evaporation-induced drying can induce different density and pore structure of G/S. Electrochemical tests illustrate that the resulting hybrid can deliver a specific capacity of 891 mAh·g⁻¹ and 575 mAh·g⁻¹ for the 1^st and 100^th cycle at a current density of 500 mAh·g⁻¹.

A new contact model between Zn_xCd_1−xS nanorods and reduced graphene oxide (RGO) was obtained by rational formation of ultrathin Zn_0.5Cd_0.5S (ZCS) nanorods on RGO through a facile oleylamine–DMSO mediated synthesis approach. The 1 D/2 D model of ZCS/RGO provides a strong contact line-to-line interface, which is not only conducive for the fast collection and transfer of photogenerated electrons but also stabilizes the ultrathin nanorod structure of ZCS. The photocatalytic test results indicated that the ZCS/RGO nanocomposites exhibit significantly enhanced photocatalytic H₂ evolution rate and cycling stability under visible light compared with free ZCS and the physical mixture of ZCS and RGO.

The front cover artwork for Issue 4/2015 is a collaboration between the University of Shanghai for Science and Technology (P.R. China) and the National Center for Nanoscience and Technology (P.R. China). The image shows the fast collection and transportation of photogenerated electrons from Zn_0.5Cd_0.5S nanorods to graphene through a line-to-line interface under visible light irradiation. See the Full Paper itself at http://dx.doi.org/10.1002/cctc.201402872.

Supercapacitors have been widely studied around the world in recent years, due to their excellent power density and long cycle life. As the most frequently used electrode materials for supercapacitors, carbonaceous materials attract more and more attention. However, their relatively low energy density still holds back the widespread application. Up to now, various strategies have been developed to figure out this problem. This research news summarizes the recent advances in improving the supercapacitor performance of carbonaceous materials, including the incorporation of heteroatoms and the pore size effect (subnanopores' contribution). In addition, a new class of carbonaceous materials, porous organic networks (PONs) has been managed into the supercapacitor field, which promises great potential in not only improving the supercapacitor performances, but also unraveling the related mechanisms.

The assembly of graphene derivatives and inorganic nanostructures opens up an exciting new field in the functionalization of nanomaterials. However, a better understanding of the interaction between graphene derivatives and inorganic precursors remains a challenge. This work provides an efficient strategy for exploring this interaction by first modifying graphene oxide with aniline, glycine, and glycyl glycine, respectively, and thus engineering the chemical microenvironments on graphene sheets for anchoring metal ions. After that, the affinities of graphene derivatives to various metal ions can be investigated with the help of a conventional electrochemical method. The method highlights the importance of graphene chemistry in hybrid preparation and provides design principles for chemical modifiers used in the construction of multifunctional carbon–inorganic nanostructures.

Hierarchical flowerlike nickel hydroxide decorated on graphene sheets has been prepared by a facile and cost-effective microwave-assisted method. In order to achieve high energy and power densities, a high-voltage asymmetric supercapacitor is successfully fabricated using Ni(OH)₂/graphene and porous graphene as the positive and negative electrodes, respectively. Because of their unique structure, both of these materials exhibit excellent electrochemical performances. The optimized asymmetric supercapacitor could be cycled reversibly in the high-voltage region of 0–1.6 V and displays intriguing performances with a maximum specific capacitance of 218.4 F g⁻¹ and high energy density of 77.8 Wh kg⁻¹. Furthermore, the Ni(OH)₂/graphene//porous graphene supercapacitor device exhibits an excellent long cycle life along with 94.3% specific capacitance retained after 3000 cycles. These fascinating performances can be attributed to the high capacitance and the positive synergistic effects of the two electrodes. The impressive results presented here may pave the way for promising applications in high energy density storage systems.

Asymmetric supercapacitor with high energy density has been developed successfully using graphene/MnO₂ composite as positive electrode and activated carbon nanofibers (ACN) as negative electrode in a neutral aqueous Na₂SO₄ electrolyte. Due to the high capacitances and excellent rate performances of graphene/MnO₂ and ACN, as well as the synergistic effects of the two electrodes, such asymmetric cell exhibits superior electrochemical performances. An optimized asymmetric supercapacitor can be cycled reversibly in the voltage range of 0–1.8 V, and exhibits maximum energy density of 51.1 Wh kg⁻¹, which is much higher than that of MnO₂//DWNT cell (29.1 Wh kg⁻¹). Additionally, graphene/MnO₂//ACN asymmetric supercapacitor exhibits excellent cycling durability, with 97% specific capacitance retained even after 1000 cycles. These encouraging results show great potential in developing energy storage devices with high energy and power densities for practical applications.