Recent Comments

    Category Chemistry/Nanotechnology

    Nanosheet Growth technique could Revolutionize Nanomaterial Production

    February 1, 2016, Categories  Physics, Technology/Electronics, Chemistry/Nanotechnology

    The new nanoscale manufacturing process draws zinc to the surface of a liquid, where it forms sheets just a few atoms thick. Credit: Xudong Wang

    The new nanoscale manufacturing process draws zinc to the surface of a liquid, where it forms sheets just a few atoms thick. Credit: Xudong Wang

    After 6 yrs of painstaking effort, Uni of Wisconsin-Madison materials scientists believe the tiny sheets of the semiconductor zinc oxide they’re growing could have huge implications for the future of a host of electronic and biomedical devices. Xudong Wang et al have developed a technique for creating nearly 2D sheets of compounds that do not naturally form such thin materials. Nanomaterials have unique electronic and chemical properties compared to identically composed materials at larger, conventional scales. Until now, they were limited to working with naturally occurring 2-D nanosheets eg graphene...

    Read More

    Researchers create first Self-Assembled 3D gyroidal Superconductor

    January 30, 2016, Categories  Physics, Technology/Electronics, Chemistry/Nanotechnology

    GA structure and sample/structure evolution from initial compounds to final NbN superconductors. (A) GA before and after processing, with the unit cell indicated by the black cube. (B) (Top) Chemical structures of compounds and (bottom) schematic of synthesis and processing steps with photographs of the final materials. Block terpolymers (ISO) are combined with the Nb2O5 sol-gel precursors in a common solvent. Hybrid block copolymer/Nb2O5 GA structures are generated by solvent evaporation–induced self-assembly. After calcination in air, the mesoporous Nb2O5 GAs are transformed to NbN GAs in a two-step nitriding process. Scale bars in all photographs represent 1 cm. NH3, ammonia.

    GA structure and sample/structure evolution from initial compounds to final NbN superconductors. (A) GA before and after processing, with the unit cell indicated by the black cube. (B) (Top) Chemical structures of compounds and (bottom) schematic of synthesis and processing steps with photographs of the final materials. Block terpolymers (ISO) are combined with the Nb2O5 sol-gel precursors in a common solvent. Hybrid block copolymer/Nb2O5 GA structures are generated by solvent evaporation–induced self-assembly. After calcination in air, the mesoporous Nb2O5 GAs are transformed to NbN GAs in a two-step nitriding process. Scale bars in all photographs represent 1 cm. NH3, ammonia.

    Building on nearly 2 decades’ worth of research, Prof...

    Read More

    You’ll never ‘Be-Leaf’ what makes up this Battery!

    January 30, 2016, Categories  Physics, Technology/Electronics, Chemistry/Nanotechnology

    Scientists baked a leaf to demonstrate a battery. Credit: Image courtesy of Maryland NanoCenter

    Scientists baked a leaf to demonstrate a battery. Credit: Image courtesy of Maryland NanoCenter

    Scientists have a new recipe for batteries: Bake a leaf, add sodium. They used a carbonized oak leaf, pumped full of sodium, as a demonstration battery’s anode. Other studies have shown that melon skin, banana peels and peat moss can be used in this way, but a leaf needs less preparation. The scientists are trying to make a battery using sodium where most rechargeable batteries sold today use lithium. Sodium would hold more charge, but can’t handle as many charge-and-discharge cycles as Li can.

    One of the roadblocks has been finding an anode material that is compatible with sodium, which is slightly larger than lithium...

    Read More

    Alternative to Platinum: Iron-Nitrogen compounds as Catalysts in Graphene

    January 28, 2016, Categories  Physics, Technology/Electronics, Chemistry/Nanotechnology

    Today, most metal and nitrogen doped carbon catalysts for ORR reveal a heterogeneous composition. This can be reasoned by a nonoptimized precursor composition and various steps in the preparation process to get the required active material. The significant presence of inorganic metal species interferes with the assignment of descriptors related to the ORR activity and stability. In this work we present a simple and feasible way to reduce the contribution of inorganic metal species in some cases even down to zero. Such catalysts reveal the desired homogeneous composition of MeN4 (Me = metal) sites in the carbon that is accompanied by a significant enhancement in ORR activity. Among the work of other international groups, our iron-based catalyst comprises the highest density of FeN4 sites ever reported without interference of inorganic metal sites.

    Today, most metal and nitrogen doped carbon catalysts for ORR reveal a heterogeneous composition. This can be reasoned by a nonoptimized precursor composition and various steps in the preparation process to get the required active material. The significant presence of inorganic metal species interferes with the assignment of descriptors related to the ORR activity and stability. In this work we present a simple and feasible way to reduce the contribution of inorganic metal species in some cases even down to zero. Such catalysts reveal the desired homogeneous composition of MeN4 (Me = metal) sites in the carbon that is accompanied by a significant enhancement in ORR activity...

    Read More