Category Chemistry/Nanotechnology

This is a closer look at the target of frozen solution that contains the building blocks for the solar cell material. Credit: E. Tomas Barraza

Delicate hybrid organic-inorganic crystals open new possibilities for light-based technologies. Materials scientists at Duke University have developed a method to create hybrid thin-film materials that would otherwise be difficult or impossible to make. The technique could be the gateway to new generations of solar cells, LEDs and photodetectors.

Perovskites are a class of materials that – with the right combination of elements – have a crystalline structure that makes them particularly well-suited for light-based applications...

The battery uses both oxygen and iron to store and release electrical energy. Credit: Zhenpeng Yao

By using iron and oxygen to simultaneously drive the electrochemical reaction, a novel battery is less expensive and has a higher capacity. On paper, it doesn’t seem like Christopher Wolverton’s super lithium-rich battery should work. For one, the novel battery uses iron, an inexpensive metal that has notoriously failed in batteries. And in another difficult feat, the battery leverages oxygen to help drive the chemical reaction, which researchers previously believed would cause the battery to become unstable. But not only does the battery work, it does so incredibly well.

Teaming up with researchers at Argonne National Laboratory, Wolverton’s group at Northwestern University developed a recha...

This is a photograph of a 3-D hydrogel construct obtained through drop-on-drop multi-material bioprintinig. Credit: Osaka University

Researchers develop a finely tuned enzyme-driven crosslinking method to glue together biological ink droplets and extend the range of cell types that can be handled by inkjet bioprinting. Such printing holds strong promise for regenerative medicine, such as in use of iPS cells. Researchers refine method of making bio-ink droplets stick to each other, enabling 3D printing of highly complex biological structures with a wide variety of cell types using inkjet printers.

Before any real applications, “bioprinting” has always faced many technical challenges...

Figure 1. (a) Three-dimensional crystal structure of YbSi2, (b) view along the a-axis, and (c) along the c-axis. (© 2017 Kurosaki et al. Phys. Status Solidi RRL 2017, 1700372. doi: 10.1002/pssr.201700372)

Researchers create a thermoelectric material (ytterbium silicide) with a high power factor at room temperature. TE materials display the thermoelectric effect: apply heat on one side, and an electric current starts to flow. Conversely, run an external current through the device, and a temperature gradient forms; i.e., one side becomes hotter than the other. By interconverting heat and electricity, TE materials can be used as either power generators (given a heat source) or refrigerators (given a power supply).

The ideal TE material combines high electrical conductivity, allowing the curr...